Research Report 1993-1994

W

SCIENCE & TECHNOLOGY

RESEARCH REPORT

1993-1994

activities and research output of Hong Kong University of Science and Technology for the period 1 July 1993 -30 June 1994. Data are accurate at the time of printing. In the event of inconsistency between information contained in the Report and other reports or where an interpretation

of

the Reports is required, the decision

of

the University Authority shall be final.

The Hong Kong University of Science & Technology© 1994

Postal Address:

Telephone:

Facsimile:

The Hong Kong University of Science & Technology Oear Water Bay

Kowloon, Hong Kong

(852) 2358 6000 (General Enquiries)

(852) 2358 6179 (Enquiries related to this Report)

(852) 2358 0545 (General Enquiries)

(852) 2358 1541 (Enquiries related to this Report)

Contents

Preface

Charts

Glossary of abbreviations

E.,esearch Projects

School of Science

Department of Biochemistry

Department of Biology

Department of Chemistry

Department of Mathematics

Department of Physics

School of Engineering

Department of Chemical Engineering

Department of Civil and Structural Engineering

Department of Computer Science

Department of Electrical and Electronic Engineering

Department of Industrial Engineering

Department of Mechanical Engineering

School of Business and Management

Department of Accounting

Department of Economics

Department of Finance

Department of Information and Systems Management

Department of Management of Organisations

Department of Marketing

School of Humanities and Social Science

Division of Humanities

Division of Social Science

Research Centre

Research Institutes

I

Centres

Biotechnology Research Institute

Cooperative Research Centre

Hainan Institute

Hongkong Telecom Institute of Information Technology

Sino Software Research Centre

Language Centre

Administrative/Service Units

v

vii

X

2

11

30

47

61

78

85

101

131

157

163

176

181

190

197

205

209

214

222

232

246

246

246

246

247

250

254

Research Report (1993-94)

Publications

School of Science

Department of Biochemistry

Department of Biology

Department of Chemistry

Department of Mathematics

Department of Physics

School of Engineering

Department of Chemical Engineering

Department of Civil and Structural Engineering

Department of Computer Science

Department of Electrical and Electronic Engineering

Department of Industrial Engineering

Department of Mechanical Engineering

School of Business and Management

Department of Accounting

Department of Economics

Department of Finance

Department of Information and Systems Management

Department of Management of Organisations

Department of Marketing

School of Humanities and Social Science

Division of Humanities

Division of Social Science

Research Centre

Language Centre

Administrative/Service Units

Awards and Prizes

Staff Index

Research Report ( 1993-94)

260

266

275

287

296

306

309

317

330

342

344

352

356

361

366

373

375

378

383

388

392

398

400

402

Preface

Research is integral to HKUST's overall education mission. Its research policies are

designed to optimise the use of research funds through quality, focus, and synergy.

The year 1993-94 has again been marked by rapid increase in the

number of students and faculty, procurement of research equipment, completion of

laboratory facilities, development of research programmes, and the strengthening of

administrative and operational support systems.

In terms of student enrolment, 1993-94 saw an increase of more than

70% from 2,249 to 3,858 (Chart 1). Concurrently, faculty numbers have increased by

more than 50%. HKUST has attracted senior faculty members of great scientific

distinction and junior members with great promise. A faculty of distinguished and

talented individuals has created an environment that is supportive and demanding,

and has firmly established quality R&D programmes for HKUST.

A strong record of publications with a total of 1,459 book chapters,

books, journal articles, conferences papers, and other forms of scholarly output was

established during the year; and success in winning competitive grants and projects

(Chart 2) attests to the quality of the research being done at HKUST.

From 1992-93 to 1993-94, the number of new research projects has

almost doubled from 134 to 251 (Chart 2) with a greater % increment for

RGC/UPGC sponsored projects than for non-RGC/UPGC sponsored ones. Funds

associated with these projects have more than doubled from $68,178 to $164,188

(Chart 2.1) with about the same% increment for both kinds of projects.

Overall, both RGC/UPGC and non-RGC/UPGC sponsored projects

helped to achieve, in part, research foci for HKUST. Optics and photonics,

microelectronics, display technology, wireless communications, protein engineering,

and neuro-biology are but a few such areas in which substantial strength has been

achieved through these projects.

Synergy has been achieved through the establishment of the

Biotechnology Research Institute, Institute for Environmental Studies, Hongkong

Telecom Institute of Information Technology, and Sino Software Research Centre in

their respective areas.

.. ... cont.

Research Report (1993-94)

v

Central to the mission of HKUST is the timely application of the fruits

of research to serve societal needs. In 1993-94, HKUST secured a partnership with

the University Corporation for Atmospheric Research (UCAR) in a project to

develop a wind shear warning system for the new Hong Kong airport at Chek Lap

Kok; and under the auspices of a wholly-owned corporation, the RandD

Corporation, HKUST has launched a commercial service to provide connections to

Internet. In a relatively short time, HKUST has built up a considerable level of

successful technology transfer.

Research Report (1993-94)

Chia-Wei Woo

Vice-Chancellor and President

Chart 1: Student enrolment by year 4,500 _4,377 4,000 3,500 3,000 2,500 2,000 1,500 1,000 500 1991-92 1992-93 1993-94 1994-95

I

D PG students DUG students

I

Research Report ( 1993-94)

Chart 2: Number of new research awards by year and type of sponsorship 300 250 200 150 .___ _ __, RGC/UPGC sponsorship Research Report ( 1993-94) 1990-91 1991-92 t::::m:::::::::::::::::::::::::::::::::l Non-RGC/UPGC sponsorship viii 251 134 1992-93 1993-94

--•1---

Total

Chart 2.1: Funds awarded for research projects by year and type of sponsorship (HK$'000s) 180,000 160,000 140,000 120,000 100,000 80,000 60,000 40,000 20,000 0

+---r====

'---' RGC/UPGC sponsorship 1990-91 1991-92 t::::::::::::j:~~ww:::)::,:l Non-RGC/UPGC sponsorship ix 164,188 1992-93 1993-94 --1•1----Total Research Report ( 1993-94)

Glossary of abbreviations

BRI

CA

CPHK

CRC

CUHK

DAG

HKBC

HKP

HKTIIT

HKU

HKUST

HNI

ITDC

JRS

MFG

MPI

PG

PI

PM

RGC

RI

SSRC

UCAR

UG

UPGC

Biotechnology Research Institute

Central Allocation Grant

City Polytechnic of Hong Kong

Co-operative Research Centre

Chinese University of Hong Kong

Direct Allocation Grant

Hong Kong Baptist College

Hong Kong Polytechnic

Hongkong Telecom Institute of Information Technology

University of Hong Kong

Hong Kong University of Science and Technology

Hainan Institute, HKUST

Industry and Technology Development Council

UK/HK Joint Research Scheme

Matching Funds Grant

Managing Principal Investigator

Postgraduate (student)

Principal Investigator

Project Manager

Research Grants Council

Research Infrastructure Grant

Sino Software Research Centre

University Corporation for Atmospheric Research

Undergraduate (student)

University and Polytechnic Grants Committee*

*

On 26 November 1994, the name of this committee was changed to University Grants Committee.

Research Report ( 1993-94)

SCHOOL OF SCIENCE

Department of Biochemistry Department of Biology Department of Chemistry Department of Mathematics Department of Physics

NEWLY-FUNDED RESEARCH

PROJECTS

Conformational stability and folding mechanism of engineered protein analogs A major goal of biotechnology is to produce medically and agriculturally valuable proteins cheaply using modern genetic, molecular biology and chemical synthetic techniques. In the process of large scale biotech manufacturing, much of the product--when it is a protein--is often either inactivated or degraded before purification. These problems are caused by protein instability and difficulties in folding. This project will find out how these difficulties can be solved. Staphylococcal nuclease, cytochrome c, and ribonuclease A have been selected as model proteins for study using various physicochemical methods: differential scanning microcalorimetry measures protein stability; circular dichroism and fluorescence spectroscopies measure protein structure in solution; stopped-flow rapid kinetics measures time course of the folding/unfolding transition and characterizes folding intermediates; amino-acid substitutions determine how different types of molecular interactions contribute to protein stability and dictate protein folding pathways of protein analogs. Data will be obtained to understand effects of salts, pH, temperature, and amino acid substitutions on protein stability and folding mechanisms, with the goal of designing superior protein analogs with therapeutic activity.

Investigator( s)

Prof. Tian Yow TSONG Biochemistry, HKUST Award Sponsor Area Start date Project no. $1,751,000 BRI/HKUST Biological Sciences 1 January 1994 BRI93-I-1 * * * * * * * * * * *

Assessment of the biodegradability and toxicity of a packing material developed by Caterly Technology Limited

Tests are being conducted to assess the biodegradability and toxicity of a newly developed packing material. To investigate its

Research Report ( 1993-94)

2

biodegradability, the material is being treated with cellulase enzymes and buried in the ground in separate experiments. Further tests are underway to determine the packing material's toxicity and carcinogenicity, the feasibility of enhancing its natural colour, its susceptibility to humidity, and the feasibility of reducing its weight.

Investigator( s) Dr Wan-keung R. WONG Biochemistry, HKUST Award Sponsor Area Start date Project no. $180,000

Caterly Technology Limited Biological Sciences

1 February 1994 CTL93 /94.SC01 * * * * * * * * * * *

Conformational study of protein and the dynamics of protein folding

This project has two parts. The first will focus on characterization of the conformational states of proteins under physiological and non-physiological conditions. FTIR, CD and luminescence spectroscopies will be used to study anisotropy, polarization, and size and shape of the protein in the folded and unfolded states. The second part will study the kinetics of protein folding using CD and fluorescence-stopped flow. For small globular proteins such as ribonuclease A, cytochrome C, bovine pancreatic trypsin inhibitor (BPTI), or staphylococcal nuclease (SNase), their functional structures are maintained by disulfide bridges, hydrophobic interactions, electrostatic forces, hydrogen bonding and van der Waals forces; as such, they are easier to study than large proteins. SNase possesses several advantages for studying relative contributions of these forces: i) It lacks disulfide bonds. ii) The gene encoding SNase has been cloned into E. coli and the protein is easily isolated and purified. iii) Relatively high yield of product (10 mg/per 2 liters culture) can be obtained. iv) It has only one tryptophan in the molecule. Therefore, conformational change can be monitored by the intrinsic fluorescence of tryptophan for the study of tertiary structure and by the CD change for studying secondary structure.

Investigator(s)

Dr Hueih-Min CHEN

Award Sponsor Area Start date Project no. $50,000 RGC Biological Sciences 1 January 1994 DAG93 /94.SC01 * * * * * * * * * * *

Brain angiotensin II, ventrolateral medulla and hypertension

Both the brain angiotensin II (Ang II) and sympathetic nervous system are essential in the genesis of hypertension. The sympathetic nervous system has been shown to mediate the effect of brain Ang II leading to alterations in arterial blood pressure (BP). However, the site(s) of action of Ang II in the brain leading to the activation of sympathetic nervous system has not been determined. One of the possible sites of action is the ventrolateral medulla (VLM), which has recently been shown to: (1) play a crucial role in the control of circulation, (2) be an important site of action of brain Ang II, and (3) be involved in the genesis of hypertentsion. The primary aim of this study is to evaluate the importance of the interaction of brain Ang II and VLM in the genesis of hypertension by: (1) correlating BP with the presence of brain Ang II, the spontaneous activities of cardiovascular neurons in VLM and the development of high BP in rats, and (2) studying the changes in BP and properties of VLM neurons after artificial suppression of the biosynthesis of brain Ang II. These experiments will provide useful information on the cause-effect relationship among brain Ang II, VLM cardiovascular neurons and BP. Another aim of this project is to determine electrophysiologically the origin of brain Ang II that exerts a tonic influence on VLM. The results of the study will be of clinical importance in the prevention and treatment of essential hypertension.

Investigator(s)

Dr T.M. WONG (PI) Physiology, HKU DrY.S.CHAN

Physiology, HKU Dr Peter H.Y. LAM

Biochemistry, HKUST $118,000 (for HKUST) Award Sponsor Area Start date Project no. RGC Biological Sciences 1 October 1993 HKU331/93M 3

Construction and analysis of peptide libraries for therapeutically active peptides Peptide libraries are large collections of peptides with wide sequence varieties in which peptides with various biological activities can be sought. We will use currently available DNA technologies to construct peptide libraries. From these libraries we will isolate and characterize peptides of three types. 1) Peptides which bind to fibrin. Such peptides will be fused to proteins such as tissue plasminogen activator (TP A) to increase the affinity of the TP A for blood clots. 2)

Peptides which bind to human hepatocytes. The purpose is to search for TP A analogs which may have improved biological effects. 3) Peptides which mimic the interaction of the hormone calcitonin with its receptor. These peptides are candidates as drugs for the treatment of various diseases with altered calcium metabolism.

Investigator(s)

Prof. Tian Yow TSONG (PI) Biochemistry, HKUST Dr James A. HACKETT

Biochemistry, HKUST Dr Peter H.Y. LAM

Award Sponsor Area Biochemistry, HKUST $1,035,000 Start date Project no. RGC Biological Sciences 1 January 1994 HKUST166/93M * * * * * * * * * * *

Construction of an efficient Bacillus subtilis system for extracellular production of heterologous proteins

The bacterium Bacillus subtilis is an efficient microorganism for extracellular production of native and homologous proteins. This feature, together with its being nonpathogenic and easy to manipulate and cultivate, make it a good potential host for the extracellular production of valuable heterologous proteins. However, due to the facts that large amounts of proteases are secreted into the medium during the stationary growth phase of this organism and that few mechanisms involved in gene regulation and protein secretion are well understood, the use of B. subtilis in extracellular production of recombinant proteins has been limited to a few proteins. In

this project we propose to adopt a systematic approach to developing a general system for engineering specific protein secretion from B.

subtilis. First, we will attempt to have a

Cellulomonas fimi cellulase gene expressed as the reporter gene in B. subtilis, using an in vitro assembled DNA cassette that contains all the strong regulatory elements of B. subtilis.

The cassette is contained in an engineered B.

subtilisfE. coli shuttle vector to facilitate its expression and manipulation in the corresponding host. Subsequent to the demonstration of expression of the reporter gene, the secretion. of its encoded cellulase from the host will be studied in detail in a controllable fashion during the vegetative growth phase of the cells. Once the production and secretion of the reporter protein are established, the whole system will be refined by modulating the regulatory functions of the cassette and growth conditions of the cells for hyperexpression and secretion of the same protein. The refined system will then be tested for its efficacy in application to other heterologous proteins by employing human epidermal growth factor (hEGF) as the testing protein. To the best of our knowledge, hEGF has never been successfully expressed in B. subtilis.

Investigator(s)

DrWan-keungR. WONG (PI) Biochemistry, HKUST Dr King-Chuen CHOW Award Sponsor Area Biochemistry, HKUST $446,000 Start date Project no. RGC Biological Sciences 1 January 1994 HKUST167 /93M * * * * * * * * * * *

Molecular basis of bacterial pathogenesis : Species-specificity in pathogenic Salmonella serovars

This project aims to identify genes on the Salmonella chromosome which are involved in the determination of host specificity. The specific scientific aims are (a) to define DNA sequences that are present in Salmonella typhi

but not in other serovars of Salmonella which are not invasive for humans when given orally, and (b) to define DNA sequences that are present in Salmonella typhimurium but not in other serovars of Salmonella which are not

Research Report ( 1993-94)

4

invasive for the mouse when given orally. As

S. typhi is completely specific for humans, the inference is that unique sequences will play a role in this host-specificity. It further follows that proteins encoded by such sequences may be useful antigens in vaccination programmes and in studying the epidemiology of Salmonella in the clinical environment. For example, if one such protein mediated attachment of S. typhi to human gastrointestinal cells, then the development of gut immunity against this protein might be an effective means of vaccination against the disease. The gene could also provide a highly specific probe for identifying Salmonella species in clinical situations.

Investigator(s)

Dr James A. HACKETT (PM) Biochemistry, HKUST Prof. Gordan DOUGAN

Award Sponsor Area Imperial College, UK £5,536 Start date Project no.

The British Council/RGC Biological Sciences 1 April1994 JRS93/49

* * * * * * * * * * *

Antibody-catalyzed epoxidation reactions for the synthesis of anti-inflammatory and antihypertensive agents

(Joint departmental project)

See PM's abstract in Department

of

Chemistry. Investigator(s) Dr Paul R. CARLIER (PM) Chemistry, HKUST DrPeterH.Y. LAM Biochemistry, HKUST Dr Kwong-Kee WAN Biology, HKUST $435,000 (Year 1) Award Sponsor Area Start date Project no. Remarks UPGC Biological Sciences 1 January 1994 Rl93 /94.SC01

Dr Wan left HKUST on 1 July 1994.

ON-GOING RESEARCH PROJECTS

Development of drug delivery systems The effects of a drug on the body result from its action on target tissues or cell types. To obtain a therapeutic response, the correct amount of active drug must be absorbed and transported to the site of action for as long as necessary. Moreover, some drugs are highly specific for the target sites, but other drugs interact with additional sites causing undesirable toxicity. In controlled drug delivery, techniques are deployed to alter the absorption, distribution and metabolism of drugs in order to achieve a time profile that is optimal with respect to the balance between therapy and toxicity. Because the process of finding new drugs is extremely costly, increasingly effort is being made worldwide to utilise the proven drugs to the best advantage. The present project establishes a broad-based programme of drug delivery research on a number of delivery systems. First, drugs such as Salbutamol are prepared in controlled-release forms that will help to maintain effective, stable concentrations of the drugs inside the body. Second, drugs like adriamycin are chemically linked to polysaccharide carriers that do not readily traverse the cell membrane. These carrier-drug conjugates are designed to improve cancer therapy by inhibiting the active expulsion of the drug from the cells. Thirdly, biocompatible surface-active agents are prepared and tested for their usefulness in facilitating the uptake of protein and peptide drugs into the body through the lungs.

InvesHgator(s)

Prof.

J.

Tze-Fei WONG Biochemistry, HKUST Award Sponsor Area Start date Project no. $2,165,600 BRI/HKUST Biological Sciences 1 September 1991 BRI91-II-1 * * * * * * * * * * *

Development of Chinese medicinal products with antioxidant properties

(Joint departmental project)

Although biological aging is unavoidable, nutritional and/ or therapeutic interventions

5

aimed at reducing the extent of age-related debilitation is a practical approach to optimizing the effectiveness of modem health management so as to contribute to the well-being of the aged as well as to reduce the costs of medical care. A growing body of scientific evidence now indicates that the accumulation of free radical (oxidant)- induced tissue damage is an important determinant in the aging process, resulting in a cluster of degenerative diseases in the terminal part of the life-span. This points to the possibility of preventing the onset and/ or progression of age-related diseases by promoting the ability of the body to combat free radicals, possibly through nutritional/ therapeutic manipulation. In view of the enormous potential of developing naturally occurring anti-aging agents/regimens from traditional Chinese medicine, we have embarked on the present project to provide a biotechnological basis for the design and manufacture of optimal herbal preparations with demonstrable effectiveness in retarding age-related debilitation.

InvesHgator(s)

Dr Robert K.M. KO (PI) Biochemistry, HKUST Dr Chun-Tao CHE

Chemistry, HKUST Dr Yun Cheung KONG

Award Sponsor Area Biochemistry, CUHK $1,326,967 Start date Project no. BRI/HKUST

Medicine, Dentistry & Health 1 September 1991

BRI91-II-2

* * * * * * * * * * *

Improvement and modification of Brassica species : Oilseed rape and vegetable brassica The application of biotechnological techniques such as plant cell culture, mutagenesis and selection has proven successful in the modification and improvement of the brassica oil crop. The primary objective of the present project is to extend this technology to the development of an additional specialty oil crop with important commercial value, like cocoa-butter, using the microspore culture system in which single-celled immature pollen is manipulated to form an embryo and eventually a whole plant. The haploid nature of the microspore is a major advantage since only one copy of the genetic material of the

plant cell needs to be manipulated, doubling to a diploid genome only upon the regeneration of the normal whole plant. The second objective of the project is to develop a haploid transformation system using microspore-derived embryos for the transfer of foreign DNA. The third objective is to improve indigenous vegetable Brassica species using the microspore culture system already in use for Brassica oil crops.

Investigator(s)

Dr Raymond S.C. WONG (PI) Biochemistry, HKUST Dr King-Chuen CHOW Biochemistry, HKUST Dr Sze-Yong ZEE Botany,HKU $1,346,700 Award Sponsor Area Start date Project

no.

BRI/HKUST Biological Sciences 1 September 1991 BR191-TII-1

* * *

*

*

* * * * * *

Development of efficient systems for the production of recombinant proteins

An E. coli excretion system developed by the PI will be employed to express mature human parathyroid hormone-like peptide and porcine growth hormone-releasing factor (pGRF), which are potentially useful for the treatment of osteoporosis and the improvement of livestock production, respectively. Both proteins have not been expressed successfully in their mature forms using other systems. To overcome the instability problems that pGRF may face during expression, the stability of this protein will be determined by circular dichroism and differential scanning microcalorimetry. The stability of the protein will then be improved by site-specific mutagenesis. With the E. coli excretion system, attempts will also be made to clone a cellobiase gene encoding a secretory cellobiase from Cellulonwnas species. The cloned cellobiase gene and its encoded protein will be characterized. Subsequently, the cellobiase gene will be co-expressed with an endoglucanase gene and an exoglucanase gene of Cellulomonas fimi in a secretory

Saccharomyces cerevisiae host. The recombinant yeast clone will be tested for its ability to degrade complex cellulosic substances and to ferment the degraded products to ethanol. To

Research Report ( 1993-94)

6

furnish a useful system to express human proteins that are improperly expressed in microbial hosts, a silkworm system employing baculovirus as a vector will be developed. The transcriptional and translational functions of the system for heterologous protein expression will be optimized. The system will then be tested for its feasibility and utility to express a number of therapeutically valuable proteins.

Investigator(s)

Dr Wan-keung R. WONG (PI) Biochemistry, HKUST Dr Peter H.Y. LAM

Biochemistry, HKUST Prof. Tian-Yow TSONG

Award Sponsor Area Biochemistry, HKUST $2,341,300 BRI/HKUST Start date Project no. Biological Sciences 1 September 1991 BR191-N-1

*

* * *

*

* * *

* *

*

The development of an expression system, based upon hybrid Salmonella flagellins, for the synthesis of protective epitopes of Staphylococcus au reus

The development of antibodies which can react with particular regions of proteins is an area of interest and importance in several spheres of biotechnological activity. First, vaccination against pathogens may be effected, in the future, by injection of humans or animals with a recombinant protein which expresses, in an appropriately "folded" form, a piece of a protein characteristic of the pathogen; immunity to this area of the protein would be protective. In the present work, it is proposed to construct recombinant genes, in which regions of vaccinally important proteins are included in the primary sequence of the genes for bacterial flagellins; these hybrid proteins are produced in large amounts by the cells, and may be readily purified by simple shearing of cell suspensions. It is known that

Salmonella flagellin genes may be manipulated in this way. Investigator(s) Dr James A. HACKETT Award Sponsor Area Biochemistry, HKUST $549,000 BRI/HKUST Biological Sciences

Start date Project no.

1 January 1993 BRI92-VI-1 * * * * * * * * * * *

Expression of the Epstein-Barr virus latent membrane protein by a baculovirus system Nasopharyngeal carcinoma (NPC) has been recognised as a major health problem in South China, where it is described as "the Guangdong tumor." Although this tumor is highly curable, mainly by radiotherapy, early diagnosis is imperative for good therapeutic results. The main objective of this project is to express a unique Epstein-Barr virus (EBV) latent membrane protein (LMP) present in NPC tissues by a baculovirus system. The protein, when produced in large quantity, will enable us to carry out the following long term studies: (a) use of this recombinant NPC-LMP polypeptide as an antigen in serological tests for NPC, either as diagnostic tool or as an indicator marker in the course of treatment of NPC; and (b) study of the role of this viral protein carcinogenesis by microinjection into normal cells. NPC-LMP, in combination with other EBV markers such as early antigen and the viral capsid antigen, may provide potent diagnostic tools for the detection of NPC. Study of the biochemical mechanism of this protein in the pathogenesis of NPC may also improve our knowledge of this major malignant disease in South China.

Investigator(s)

Dr Peter H.Y. LAM

Biochemistry, HKUST Award Sponsor Area Start date Project no. Remarks $113,000 RGC Biological Sciences 1 October 1991 DAG91 /92.SC11 Project completed * * * * * * * * * * * Direct transformation of imbibing seeds Cell transformation is an important technique in genetic engineering. Through such a process, DNA fragments can be cloned and subcloned, gene products can be over-expressed or tested in the chosen host organism, and the cis-acting elements of certain genes can be analysed. Unfortunately, such an important technique is not well

7

developed in plant molecular biology. Many methods have been devised for the introduction of foreign DNA into plant cells but all of them have limitations. In this project, we will explore the possibility of transforming seed embryos directly so as to circumvent all of the limitations. In this study, seed embryos will be prepared and soaked with plasmid DNA solutions of different salt types and concentrations for different durations. The plasmid used is a shuttle vector that can be propagated in both E. coli and plant. The treated embryos will be allowed to germinate. Plasmids in the plant cells will be examined through Southern blottings, and gene products encoded by the shuttle plasmid will also be analysed. Investigator(s) Dr King-Chuen CHOW Biochemistry, HKUST Award Sponsor Area Start date Project no. $30,000 RGC Biological Sciences 1 November 1992 DAG92/93.SC01 * * * * * * * * * * *

Structure and function of transfer RNA for tryptophan

Earlier studies by us have lead to the cloning, gene-sequence determination, purification and kinetic investigation of the tryptophanyl-tRNA synthetase from Bacillus subtilis. In the present study we are investigating through cloning and mutagenesis the structure and function of the tRNA component. Currently considerable interest at both the basic and therapeutic levels is focused on the various roles of tRNA molecules in addition to their participation in protein synthesis: tRNA coding regions serve as promoters for transcription by eukaryotic RNA polymerase III, and tRNAs also function as primers for retroviral reverse transcriptases. In particular, tRNA is the primer in the retrotranscription of the avian myeloblastosis virus. The cloning and mutagenesis of tRNA will establish methodologies that will be useful also for future research to define the structural requirements for the primer activity of tRNA.

Investigator(s)

Prof. J. Tze-Fei WONG Biochemistry, HKUST

Award Sponsor Area Start date Project no. Remarks $390,000 RGC Biological Sciences 1 July 1991 HKUST006/91 Project completed * * * * * * * * * * *

Factors controlling extracellular production of recombinant proteins in Escherichia coli

Excretion in Escherichia coli is an unusual

process by which the proteins are exported to the culture medium of the bacterial cells. Applications of this process have been developed only recently, and it is now being used to produce and purify a number of proteins. Recently an excretion system was developed by the investigator of this project

using E. coli JM101 strain in conjunction with

an expression/ excretion vector, plac1Qpar8. The goal of this project is to identify the factors which may have effects on the excretory

efficiency of a Cellulomonas fimi exoglucanase

in the E. coli excretion system mentioned

above. The research activities involve the cloning and expression of the exoglucanase product, and the studies of the effects of the regulatory gene sequences (which include the promoter, ribosome-binding site and signal sequence), on the excretory efficiency of the exoglucanase. Investigator(s) Dr Wan-keung R. WONG Biochemistry, HKUST Award Sponsor Area Start date Project no. Remarks $380,000 RGC Biological Sciences 1 July 1991 HKUST008/91 Project completed * * * * * * * * * * *

Biosynthesis of storage lipids in Brassica napus: Properties of diacylglycerol acyltransferase

The purpose of this research is the purification and characterization of one of the key enzymes in the biosynthesis of the oil molecule as a prerequisite for the genetic

engineering of canola oil. Canola is an

improved form of rapeseed (Brassica spp.)

especially selected by plant breeders for the

Research Report ( 1993-94)

8

production of edible oil. It is the third major

oil crop of the world. One reason canola has become a major oil crop is the improvement in its quality over rapeseed, namely the removal of undesirable erucic acid from its oil. Further improvements or modifications to meet the demands of consumers and industries will best be achieved by advanced recombinant DNA technology in the direct manipulation of the genes for the enzymes that control oil synthesis. The usefulness of this technology

has been demonstrated in oilseed Brassica in

the transfer of disease resistance genes to certain antibiotics and herbicides. The lack of knowledge of the biochemistry of the enzymes

involved in the oil synthesis for Brassica has

precluded the application of this recombinant DNA technology for further modifications and improvements of canola. This study of the enzyme diacyglycerol acyltransferase intends to provide opportunities to use recombinant DNA technology in further modification of canola. Investigator(s) Dr Raymond S.C. WONG Biochemistry, HKUST Award Sponsor Area Start date Project no. $402,000 RGC Biological Sciences 1 September 1992 HKUST095 /92M * * * * * * * * * * * Development of hemoglobin-based technologies and instrumentation

(Joint departmental project)

The binding of oxygen to hemoglobin (Hb) serves a vital function in the body. Technologically the measurements of oxygenated and deoxygenated forms of Hb provide valuable information on the physiological status of the human body, and therefore play a key role in clinical medicine. The Hb-oxygen system is also currently undergoing development as a molecular gill for use in submarines and underwater human activities. In view of this, the objective of this project is to bring together three lines of expertise on the Hb-oxygen system to establish a basis for the development of technologies serving clinical medicine and molecular gill design.

Investigatar(s)

Prof.

J.

Tze-Fei WONG (PM) Biochemistry, HKUST Prof. Peter W. CHEUNG

Electrical & Electronic Engg, HKUST Dr Wa-Hung LEUNG Chemistry, HKUST Award Sponsor Area Start date Project no. $608,500 (Year 1) UPGC Biological Sciences 1 November 1992 RI92/93.SC04 * * * * * * * * * * *

Development of a rapid and low-cost drug screening procedure utilizing yeast genetics and recombinant DNA technology

(Joint departmental project)

See PM's abstract in Department of Biology. Investigatar(s)

Dr Yung-Hou WONG (PM) Biology, HKUST

Dr Chun-Tao CHE, Chemistry, HKUST Dr Robert K.M. KO Biochemistry, HKUST Award Sponsor Area Start date Project no. $562,000 (Year 1 & 2) UPGC Biological Sciences 1 February 1993 RI92/93.SC05 * * * * * * * * * * *

Cloning and expression of a cellobiase gene from Cellulomonas biazotea in Escherichia coli

In screening five Cellulomonas species for secretory enzymes able to cleave

p-nitrophenyl-~-D-glucoside (pNPG) and cellobiose, only C. biazotea and C. flavigena

scored positive. The chromosomal DNAs of these were partially digested with Psti, and the restriction fragments were shotgun- cloned into the Pstl site of an excretion vector, pM. E. coli transformants of the two banks of recombinant plasmids were screened for excretory activity in cleaving

4-methylumbelliferyl-~-D-glucoside. Of 5,000 clones, 25 tested positive. From these, one--harboring a C. biazotea construct and designated pBZ4.7--was able to grow in liquid media containing cellobiose as the sole carbon source. The cellobiase activity expressed by

9

pBZ4.7 was excreted in part from E. coli. The cellobiase gene insert was revealed by restriction analysis to consist of two Psti fragments, 0.75 kb and 3.95 kb in length. Apparently, both fragments are essential to cellobiase expression. DNA sequencing results obtained so far reveal that the gene insert has a high G+C content, which is typical of Cellulomonas DNA. The potential application of cellobiase in paper hydrolysis was demonstrated by its cooperative action with an endoglucanase and an exoglucanase of C. fimi in digesting filter paper.

Investigator( s)

Dr Wan-keung R. WONG (Supervisor) Biochemistry, HKUST

Mr Wai-Kei CHAN

Award Thesis

Sponsor HKUST

Area Biological Sciences

Start date 1 September 1991 * * * * * * * * * * *

Expression of the 19 kDa antigen of Mycobacterium tuberculosis and its fusion protein in E. coli system

The 19 kDa antigen of Mycobacterium tuberculosis (TB19) is a highly immunogenic protein found in most mammalian species including mouse and human. We believe that this protein, which contains several T -cell epitopes, would enhance the immunogenicity of other antigens presented together with it. In this study, a polymerase chain reaction was employed to remove the major B-cell epitope of this antigen. This truncated protein (TB19') coding sequence was cloned into three expression vectors, pTrc99A, pTM-N and pET-15b. The coding sequence of human calmodulin (hCaM) and the fusion sequence of TB19' and hCaM (TB19'-hCaM) were also cloned into the three expression vectors. Our results revealed that DNA sequences cloned in pET -15b showed the most satisfactory expression level for all of the three proteins. The availability of these proteins will enable us to evaluate the immunoenhancing effect of TB19'.

Investigator(s)

Dr Peter H.Y. LAM (Supervisor) Biochemistry, HKUST Miss Amanda K.C. HO

Award Thesis

Sponsor Area Start date HKUST Biological Sciences 1 August 1992 * * * * * *

*

* * * *

Excretory production of a Cellulomonas fimi exoglucanase by Escherichia coli

An excretion reporter construct, taciQpar8cex, was assembled by cloning the Cellulonwnas

fimi exoglucanase gene, cex, into the Tac expression/ excretion plasmid, laciQpar8. E. coli JM101 harboring taciQpar8cex was shown to produce extracellular exoglucanase (Exg) activity. Derivatives of taciQpar8cex were constructed for studies of the factors important to excretion of Exg in JM101. The first derivative engineered was taciQpar8cex/NB, in whlch a unique BamiD

site had been introduced into a non-essential region of taciQpar8cex. Quantitatively, taciQpar8cex/NB and taciQpar8cex/ ompA-, in which 14 codons of the ompA leader had been deleted, were incapable of expressing extracellular Exg in JM101. Another derivative, laciQpar8cex, was constructed by replacing the tac promoter in taciQpar8cex with the lac promoter. Cell growth, plasmid stability and ability to produce excretory Exg were compared between strains

JM101(taciQpar8cex) and

JM101(1aciQpar8cex). There were no major differences between the two strains when the inducer, IPTG, was absent. However, when

IPTG was present, cells of

JM101(1aciQpar8cex) grew faster, produced Wgher biomass, and exhlbited greater plasmid stability and better excretory Exg activity than of JM101(taciQpar8cex). The efficient performance of JM101(laciQpar8cex) for excretory Exg production suggests that the system may be optimized and extended for use in other proteins.

Investigator( s)

Dr Wan-keung R. WONG (Supervisor) Biochemistry, HKUST

Mr Tin-Long LAM

Award Thesis

Sponsor HKUST

Area Biological Sciences

Start date 1 September 1991 * *

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Research Report (1993-94)

10

Expression of a human erythropoietin analog in the silkworm using a B. mori baculovirus system

The baculovirus protein expression system is rapidly becoming one of the methods of choice in the expression of recombinant proteins in eukaryotic cells. In this work, we have utilized the Bombyx mori nuclear polyhedrosis virus to express a human erythropoietin (Epo) analog in the B. mori derived cell line BMN as .well as the B. mori larvae under the transcriptional control of the strong BmNPV polyhedrin promoter. In order to enhance the expression level, we have constructed two new baculovirus transfer vectors, pBMEpo'-RBS-SP and pBMEpo'-RBS, by inserting the putative Sf9 ribosomal binding site sequence, with or without a signal peptide, into the pBM030 transfer vector. Our results showed that the putative ribosomal binding site sequence has positive effects on the human Epo analog expression level, though not as high as that in the Autographa californica

nuclear polyhedrosis virus system. However, the ·presence of the signal peptide enhances the expression level significantly. Furthermore, the signal peptide is essential in the secretion and glycosylation of the Epo analog. In conclusion, our findings suggest that the protein expression level in the silkworm can be improved by modifying the 5' flanking region of the foreign gene in the transfer vectors. Moreover, the B. mori larvae can serve as an excellent source of engineered proteins in large quantities.

Investigator(s)

Dr Peter H.Y. LAM (Supervisor) Biochemistry, HKUST Miss Dan-Qing LI

Award Thesis

Sponsor HKUST

Area Biological Sciences

Start date 1 August 1992 * * * * * *

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* *

* *

Isolated microspore culture system for Brassica parachinensis

Brassica parachinensis is one of the major vegetables consumed in Hong Kong and neighbouring regions. It would be of great value if a system for microspore culture of thls vegetable could be established. Accordingly, in this study, factors including bud length,

individual plant, culture induction temperature, sucrose concentration and pH value have been examined in order to optimize the microspore culture of this important vegetable. This report describes for the first time successful microspore culture of

Brassica parachinensis. Established conditions include: the use of buds of length between 2-3 mm; incubation temperature at 32 degrees C for the initial 24 hours and maintained at 25 degrees C for the subsequent culture period; and culture medium with sucrose concentration of 13-15% and an irtitial pH of

6.0-6.5. Investigator(s)

Dr Raymond S.C. WONG (Supervisor) Biochemistry, HKUST

Miss S.C. MAK

Award Thesis

Sponsor HKUST

Area Biological Sciences

Start date 1 September 1991 * * * * * * * * * * *

Extracellular expression of porcine growth hormone releasing factor by Escherichia coli The gene sequence encoding the 44 amino acid porcine growth hormone releasing factor (pGRF) was assembled in vitro using two synthetic oligonucleotides with lengths of 87 and 88 nucleotides, respectively. Through subcloning and site-specific mutagenesis of the pGRF gene fragment in the tac excretion cassette carried on Ml3mpl9, a precise fusion of the pGRF to the OmpA signal peptide was created. With the use of this ompA-pGRF

recombinant construct, information on the hydropathy plot of pGRF, and site-specific mutagenesis, two mutants of pGRF potentially resistant to trypsin and chymotrypsin were generated by individually replacing the lOth Tyr residue and the 34th Arg residue of pGRF with alanine. Both the wild-type and the mutant om pA-pGRF constructs were subcloned into the excretion vectors, pM and lac1Qpar8, for expression in E. coli. Northen blot analysis of the messenger RNAs collected from cells harboring the recombinant constructs revealed that both the wild-type and the mutant ompA-pGRF constructs were able to produce a strong transcriptional signal. With the use of ELISA and various chromatographic methods, immunoactivity of pGRF was detected in the culture supernatant

11

of an IPTG induced E. coli clone harboring the

ampA-pGRF construct.

Investigator(s)

Prof. Tian-Yow TSONG (Supervisor) Biochemistry, HKUST Mr Po-Ming TAM

Award Thesis

Sponsor HKUST

Area Biological Sciences

Start date 1 September 1992 * * * * * * * * * * *

Expression of human tissue plasminogen activator using the Bombyx mori nuclear polyhedrosis virus system

In this study, we utilized the BmNPV to express active human tissue plasminogen activator, a potent fibrinolytic agent, in BmN cells and the silkworm Bombyx mori. Two expression vectors, one containing the original t-PA eDNA and the other a mutated t-PA eDNA, were constructed. A short putative ribosomal binding site sequence was inserted immediately before the signal peptide. Recombinant viruses were generated from these vectors, and were used to infect BmN cells and B. mori larvae. Radial caseinolysis assay was employed to check the activities of the expressed products. Our study showed that active human t-P A could be expressed by the BmNPV system. Moreover, the putative ribosomal binding site upstream of the t-PA · gene did enhance the level of expression and secretion. Characterization and purification of the expressed products are now in progress.

Investigator(s)

Dr Peter H.Y. LAM (Supervisor) Biochemistry, HKUST Mr Rocky P.N. TANG

Award Thesis

Sponsor HKUST

Area Biological Sciences

Start date 1 August 1992 * * * * * * * * * * *

NEWLY-FUNDED RESEARCH

PROJECTS

Ecological study of mangrove stands in Hong Kong

See PM' s abstract in Research Centre. Investigator( s)

Dr Yuk-Shan WONG (PM) Research Centre, HKUST Biology, HKUST

DrNoraF.Y. TAM

Biology & Chemistry, CPHK Mr Zhiping LIU

Award Sponsor

Fu Tian Nature Reserve $620,000

Area Start date Project no.

Agriculture & Fisheries Dept., HK Government

Biological Sciences 1 January 1994 AFD93/94.RC01 * * * * * * * * * * *

Pilot trawl survey: Data analysis and reporting for the South of Ninepins Environmental Impact Assessment (SNI EIA) One of the key issues identified as part of the Environmental Impact Assessment (EIA) of the potential marine borrow area south of the Ninepin Islands (SNI) was the impact of dredging on marine fisheries. This project was a pilot study to determine the baseline condition of demersal fish in and around the SNI borrow area to provide information for assessing the desirability of dredging in this area. A fishing trawl survey of demersal fish was conducted during December 1993 and January 1994. A total of 38 trawl sets were collected. Although 22 sets were made in the proposed borrow area, only two were successful because the very rough seabed and construction waste damaged the nets. Forty-three demersal fish species were recorded from a total catch of 1133 individuals. The most abundant fish in SNI is Apogon kiensis

(cardinal fish, 62.4%), followed by Collichthys lucidus (croaker, 8%), and Arnoglossus tenuis

(lefteyed flounder, 4.2%). In comparing control and borrow areas, no significant differences in species composition, relative abundance, diversity and evenness indices, or fish abundance indices were found, but these

Research Report ( 1993-94)

12

results--from such a small sample-should be interpreted with caution.

Investigator(s) Dri-HsunNI Biology,HKUST Award Sponsor Area Start date Project no. Remarks $103,030 Binnie Consultants Ltd. Biological Sciences 1 December 1993 BCL93/94.SC01(A) Project completed * * *

*

* * * * * * *

Pilot trawl survey: Data analysis and reporting for the independent Environmental Monitoring and Audit (EM&A) of dredging in the East Lamma Channel

An independent Environmental Monitoring and Audit (EM&A) of dredging effects on fisheries in the East Lamma Channel so as to provide baseline data that can be used for comparison with data collected in the future during and after approved dredging projects. Thirty-six ten-minute fishing trawl sets, with twin beams along four transect lines, were conducted on December 16, 1993 for statistical comparison; the sets included daytime and night-time periods and were conducted both inside and outside the borrow area. There were 36 demersal fish species in a total catch of 336 individuals. No species was dominant. The most abundant fish was Sicyopterus japonicus with a relative abundance of 18.5% of the total fishes caught. No significant differences in species composition, relative abundance, diversity and evenness indices, or fish abundance indices were observed, either in comparing daylight and night-time periods, or in comparing control and borrow areas.

Investigator(s) Dri-HsunNI Award Sponsor Area Biology, HKUST $101,308 Start date Project no. Remarks Binnie Consultants Ltd. Biological Sciences 1 December 1993 BCL93/94.SC01(B) Project completed * * * * * * * * * * *

Trawl survey programme: Data analysis and reporting for the Environmental Monitoring and Audit (EM&A) for Contaminated Mud Pit (CMP) II east of Sha Chau

The objective of this project is to monitor the regional, cumulative and pit-specific impacts of dredging, contaminated mud disposal and capping of CMP II, providing continuity to the existing programme and accounting for the effects of previous operations at CMP I and other major dredging and filling works nearby. Fishing trawl surveys are conducted once a month at six stations east of Sha Chau for a period of 24 months. Fish species composition is recorded and abundance indices are calculated. A species diversity index (H') and evenness index (J') is calculated for each fishing set. Monthly variations and comparison are monitored for any significant changes which might be due to contaminated mud disposal and capping.

Investigator(s) Dri-HsunNI Biology, HKUST $609,712 Award Sponsor Area Start date Binnie Consultants Ltd Biological Sciences 1 January 1994 Project no. BCL93 /94.SC02 * * * * * * * * * * *

Immunosuppressive peptides resemble microtubule-binding domains

Cyclosporin, a drug that can reduce the human immune response, greatly improves organ survival rate after transplantation. The therapeutic window of cyclosporin is narrow and is limited by adverse reactions, particularly in causing kidney damage. Cyclosporin and related agents have been shown to bind to cellular proteins, designated as immuniphilins. Immunophilins may be involved in the transduction of signals that lead to the activation of the immune system. Similarity found between immunophilins and proteins associated with microtubules, i.e., the skeletal framework inside a cell, suggests that immunophilins may bind to microtubules to form a complex. Studies on such a complex will provide new insights on the regulation of immune suppression and may make it possible to develop novel peptide drugs that target the microtubule-binding domains of

13

immunophilins. This project will also lead to the development of techniques and expertise in using synthetic peptides as therapeutic agents in Hong Kong.

Investigator(s) Dr Mun-Fai LEUNG Biology, HKUST Award Sponsor Area Start date Project no. $263,000 BRI/HKUST Biological Sciences 1 April1994 BRI93-I-2 * * * * * * * * * * *

Mechanisms of retention, mobilization and detoxification of pollutants from wastewater by mangrove ecosystems

(Joint departmental project)

See PI's abstract in Research Centre. Investigator(s)

Dr Yuk-Shan WONG (PI)

Research Centre, HKUST Biology, HKUST

Dr Nora F.Y. TAM

Biology & Chemistry, CPHK Dr Xiang-Ming LI

Chemical Engineering, HKUST $483,000 (Year 1) BRI/HKUST Award Sponsor Area Start date Biological Sciences 1 January 1994 BRI93-II-1 Project no. * * * *

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* * * * * *

Remote sensing studies of marine pollution in Hong Kong/Pearl River

See PM's abstract in Research Centre. Investigator(s)

Prof. Jay-Chung CHEN (PM) Research Centre, HKUST

Mechanical Engineering, HKUST DrMingFANG

Research Centre, HKUST Dr Yuk-Shan WONG

Award Sponsor Area

Research Centre, HKUST Biology, HKUST

$4,390,000

Croucher Foundation Biological Sciences

Civil Engineering & Applied

Start date Project no. Mathematics 1 July 1993 CF92.003 * * * * * * * * * * *

Study on the application of mangrove swamp as a natural wetland system for wastewater treatment

See PM's abstract in Research Centre. Investigator(s)

Dr Yuk-Shan WONG (PM) Research Centre, HKUST Biology, HKUST

Dr Nora F.Y. TAM

Biology & Chemistry, CPHK Prof. C.Y. LAN

Zhongshan University, PRC Prof. G.Z. CHEN Zhongshan University, PRC $362,000 Award Sponsor Area Start date Project no. Croucher Foundation Biological Sciences 1 May1994 CF93/94.RC02 * * * * * * * * * * *

Molecular and cytogenetic analysis of the role of tumor suppressor genes and oncogenes in the development of esophageal carcinomas in Hong Kong

The exceptionally high incidence of esophageal cancers in Chinese populations makes this study of importance. In Henan and Shanxi provinces of the PRC, the annual mortality from this carcinoma may be as high as 145/100,000. Our study will be a comparative analysis of different contributing factors involved in esophageal cancers among high-risk, moderate-risk, and low-risk Chinese populations. Tumor suppressor genes such as p53 will be examined. Molecular and cytogenetic techniques will be used to examine the frequency of mutations in these tumors. We hope to identify chromosome-specific markers which may be involved in tumorigenesis.

Investigator(s)

Dr Maria Li LUNG (PI) Biology, HKUST Ms Ceclia M.C. TANG

Clinical Path., Tuen Mun Hospital

Research Report ( 1993-94)

14

Dr Kwok-Wai LAU Surgery, CUHK MrSai-KiO

Radiotherapy & Oncology, Tuen Mun Hospital

Prof. Yong-Sheng ZONG

Award Sponsor Area

Pathology, Sun Yat-sen U., PRC $1,250,940 Start date Project no. Croucher Foundation Biological Sciences 1 January 1994 CF93 /94.SC03 * * * * * * * * * * *

GABA (Y-aminobutric acid) receptor cells in abalone larvae

Y -aminobutyric acid (GABA) is a potent vertebrate inhibitory neurotransmitter which induces settlement and metamorphosis in abalone larvae, including species such as

Haliotis kamtschatkana. It has been hypothesized that GABA initiates behavioral and morphogenetic changes by binding to an epidermal sensory receptor located on the cilia of specific specialized larval organs, resulting in the activation of a complex signal transduction mechanism that leads to metamorphosis. In this study, the uptake of [3H]-GABA into metamorphically competent larvae of H. kamtschatkana was visualized over a 1h time sequence using autoradioactive techniques. After a 15-min incubation, [3H]-GABA was found in the whole body, with the foot and mantle appearing to be the most active sites of uptake. After 60 minutes all the internal organs including the larval nervous system had incorporated varying amounts of radioactive label. No specific site of [3H]-GABA uptake at the epidermal surface was detected. The rapid transport of this · neurotransmitter into the larva suggests it behaves like any other amino acid, as active uptake of dissolved amino acids has been demonstrated in a number of larval molluscs, including the abalone species H. rufescens. We suggest that GABA induces abalone settlement and metamorphosis by influencing various sites, including those located within the larval nervous system and other morphogenetically active tissues, rather than on a specific epithelial chemoreceptor.

Investigator(s)

Prof. Fu-Shiang CHIA Biology, HKUST

Award Sponsor Area Start date Project no. $50,000 RGC Biological Sciences 1 January 1994 DAG93 /94.SC02 * * * * * * * * * * *

Study of the function of PECAM-1 in vitro and in vivo

Whenever inflammation occurs, leukocytes (white blood cells) migrate to the inflammation site to defend the body. How do the leukocytes travel and ultimately reach the inflammation site? Research has shown that several cell adhesion molecules (CAMs) are involved in this process. Platet/ endothelial cell adhesion molecule 1 (PECAM-1) is one CAM involved in this immune response. To demonstrate the function of PECAM-1 in vivo, a mouse model was chosen. Mouse PECAM-1 eDNA was cloned and sequenced and in vitro assay was performed, identifying the function of mouse PECAM-1 as homophilic, meaning that mouse 1 binds only to other mouse

PECAM-1. To determine whether mouse PECAM-1 mediates leukocyte transmigration through endothelial cell junctions to inflammation sites, I propose the following series of experiments. First, I propose to block the adhesion of mouse PECAM-1 by injecting mice with reagents which will adhere to mouse PECAM-1, such as polyclonal and monoclonal anti-murine PECAM antibodies, soluble mouse PECAM, and chimeric molelucles of mouse PECAM linked with human immunoglobin (IgG). Second, I propose to use gene knockout techniques to produce mice lacking PECAM-1 and to assay the function of PECAM-1 in these PECAM-1-deficient mice to determine whether it is homophilic in vivo. Through these experiments, I believe the true function of PECAM-1 will be elucidated.

Investigator(s) DrYongXIE Award Sponsor Area Biology, HKUST $50,000 RGC Start date Project no. Biological Sciences 1 December 1993 DAG93/94.SC03 * * * *

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15

Ectopic expression of mouse agouti gene in cells carrying viable yellow mutation

Adult mice carrying the viable yellow mutation (Avy) at the agouti locus bear completely yellow coats. Besides affecting coat color, A vy mutation is associated with increased susceptibility to a wide variety of spontaneous and chemically induced tumors. Recently, our laboratory has established permanent fibroblast cell lines from newborn A vy

I

a and control congenic a/ a mice from VY and YS inbred strains. Studies have shown that, regardless of inbred strain, all A vy

I

a cell lines exhibit a striking degree of spontaneous transformation in culture compared to a/ a-derived lines which do not show spontaneous transformation. In addition, agouti mRNA could be detected in the A vy

I

a-derived, but not in a/ a-derived cells, which supports the hypothesis of a direct role for agouti expression in initiation of spontaneous transformation. This project specifically aims to address the question of whether the agouti gene or a closely linked gene is responsible for the elevated levels of spontaneous transformation in A vy

I

a cell lines. To do this, a construct- carrying agouti eDNA will be introduced into the control a/ a cell lines, and the effect of overexpression of the agouti gene in those cell lines will be observed.

Investigator(s) Dr W.L. Wendy HSIAO Biology, HKUST Award Sponsor Area Start date Project no. $50,000 RGC Biological Sciences 15 November 1993 DAG93 /94.SC04 * * * * * * * * * * *

Identification and characterization of novel neurotrophic factors and receptors

The shaping of the nervous system during normal development is accompanied by the process of naturally-occurring neuronal cell death. During this critical period, developing neurons compete for limited amounts of target-derived neurotrophic factors such that only neurons making the appropriate connections with their targets survive. Such a selective process is therefore thought to be required for the appropriate wiring of neural connections and interactions. In addition to

their effects on neuronal survival, neurotrophic factors have also been shown to have other activities with respect to cell proliferation, differentiation, maintenance, and injury. There are now two major classes of neurotrophic factors; one is collectively known as the neurotrophins (with nerve growth factor being the prototypical one), and the other is represented by ciliary neurotrophic factor. Factors in both classes act on their target cells by activating distinct receptor systems. This research project is focused on the identification and characterization of novel neurotrophic factors and receptors that are related to the existing ones, using the approach of homology cloning.

Investigator(s) DrNancyY.Y. IP Biology, HKUST Award Sponsor Area Start date Project no. $150,000 RGC Biological Sciences 1 December 1993 DAG93 /94.SC05 * * * * * * * * * * *

Exploration of the physiological function of ethylene in growth and development of red and brown algae

Ethylene is an important plant hormone involved in many aspects of plant growth and development. Biochemical and molecular biological study of ethylene biology in higher plants has resulted in the successful establishment of the ethylene biosynthesis pathway, isolation of ACC synthase and oxidase, and cloning of genes encoding these enzymes. However, little is known about the biosynthesis and physiological function of ethylene in marine plants. The primary goal of this research project is to isolate and characterize the genes involved in ethylene biosynthesis in marine algae, to study the temporal and spatial regulation of their gene expression during growth and development, and to characterize the biochemical features of enzymes coded for by those genes. The long term goal is to explore the physiological function of ethylene in marine algal growth and development by correlating particular algal physiological and development changes to the tissue-specific and developmentally-regulated ethylene production. The ultimate goal is to improve the production and quality

Research Report (1993 -94)

16

of certain commercially valuable seaweeds by manipulating ethylene biosynthesis.

Investigator(s) DrNingLI Award Sponsor Area Biology, HKUST $50,000 RGC Start date Project no. Biological Sciences 1 November 1993 DAG93/94.SC06 * * * * * * * * * * *

Enhancement of the quality and growth rate of abalone by genetic and ecological manipulation

Abalone is an important seafood and has been cultured intensively in many coastal regions in recent years. The mariculture industry has suffered, however, due to high mortality and slow growth of the abalones. This research attempts to improve both the quality and growth rate of the offspring of two species of abalone, Haliotis discus hannai Ino and H.

diversicolor. Its specific objectives are: 1) to induce triploid or tetraploid progenies by blocking the release of the first polar body (PB1) or second polar body (PB2) during abalone oogenesis; and 2) to optimize the physical conditions of brooding stocks through selective feeding. The proposed studies are fundamental to the understanding of the reproductive biology and larval ecology of abalones and may provide key information on the relationships between environmental conditions and reproductive strategies, as well as between environmental conditions and mortality with respect to this organism. The proposed research on the induction of polyploidy will generate background · knowledge for developing a long-term selective breeding program in order to create new strains with higher survival and growth rates. Investigator(s) Dr Peiyuan QIAN Biology, HKUST Award Sponsor Area Start date Project no. $100,000 RGC Biological Sciences 1 March 1994 DAG93 /94.SC18 * * *

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