• 沒有找到結果。

植物細胞的生長與分化2

N/A
N/A
Protected

Academic year: 2021

Share "植物細胞的生長與分化2"

Copied!
17
0
0

加載中.... (立即查看全文)

全文

(1)植物生理 藻類起源與質體 Origins of Algae and their Plastids 李澤民 海洋植物研究室 海洋生物科技暨資源學系 國立中山大學 高雄 台灣.

(2)

(3) plastid • • • •. Chloroplast Chromoplast Proplastid Leuoplast, amyloplast. • Chloroplast R.R. • Pyrenoid: RuBisco+stores.

(4) Plastid origin and algal evolution. Hedges, S. Blair et al. (2004) "A molecular timescale of eukaryote evolution and the rise of complex multicellular life" BMC Evolutionary Biology 4:2.

(5) 請看文章7.9. 補充資料 PSII PSI 演化假說. Major LhcII 是可以移動到PSI =state 2 綠藻保有此類的能力較高等植物大,綠藻 Minor LhcI 也會移動.

(6) Gene exchange and loss.

(7) http://www.thescientist.com/?articles.view/articleNo/33711/title/StealMy-Sunshine/.

(8) Fig. 1. Tree of eukaryotes and diversity of plastid-bearing eukaryotes.. This was perhaps most obvious in thethe euglenids, whose plastids phylogenetic were quickly recognized to share a diversity of plastidnumber of characteristics with bearing groupstheir is clear: green algae, whereas flagellar apparatus was more akin they are scattered across to four that found in the parasitic and of the five major nonphotosynthetic kinetoplastid groups of eukaryotes. protozoa (Leedale, 1967⇓; Kivic and Walne, 1984⇓). Molecular systematics further reinforced these contradictions by demonstrating that euglenids and trypanosomes were closely related at the nuclear level to the exclusion of green algae (Sogin et al., 1986⇓). Keeling P J Am. J. Bot. 2004;91:1481-1493. www.amjbot.org.

(9) PRIMARY PLASTIDS • Primary endosymbiosis.

(10) Primary endosymbiosis refers to the original uptake and retention of a cyanobacterium by a eukaryote • These plastids are bound by two membranes, which are derived from the inner and outer membranes of the Gram-negative cyanobacterium (Jarvis and Soll, 2001⇓). • The once free-living prokaryote was reduced and transformed into the organelles we see today, partly by the loss of much of its genome and the transfer of most of the remaining genes to the nucleus of its host..

(11) Fig. 2. Primary and secondary endosymbiosis.. Keeling P J Am. J. Bot. 2004;91:1481-1493. www.amjbot.org.

(12) Primary endosymbiosis refers to the original uptake and retention of a cyanobacterium by a eukaryote • The protein products of most of these nuclear genes continue to function in the plastid, and they are posttranslationally targeted there by means of an Nterminal leader called a transit peptide. • Transit peptides are recognized by protein complexes in the inner and outer membranes of the plastid (called TICs and TOCs) that direct the translocation of proteins across the membranes (McFadden, 1999⇓). • Primary plastids are found in three major lineages: glaucophytes, red algae, and green algae (including plants)..

(13)

(14) • Glaucophytes (glaucocystophytes) are a small group of microscopic algae found in freshwater environments. There are only about 13 species of glaucophytes, and although not particularly common in nature they are important because they occupy a pivotal position in the evolution of photosynthesis in eukaryotes (see later). They also represent an intermediate in the transition from endosymbiont to plastid in that they are unique among plastids in retaining the prokaryotic peptidoglycan layer between their two membranes. Glaucophyte plastids contain photosynthetic pigments chlorophyll a, phycobilins, and phycobilisomes, small particles organized on the outer face of thylakoid membranes that are also found in cyanobacteria. (For a review on glaucophytes, see Bhattacharya and Schmidt, 1997⇓; Steiner and Loffelhardt, 2002⇓.).

(15) • Red algae are a very large and diverse group of microscopic algae and macroalgae that are present in freshwater and common in marine environments. Red algal plastids contain chlorophyll a, phycobilins, and phycobilisomes. For a review of red algae, see Saunders and Hommersand (2004) in this issue..

(16) • Green algae are another large and diverse group of predominantly freshwater algae whose plastids harbor chlorophylls a and b. Green algae are roughly divided into chlorophytes and charophytes. Charophytes are the ancestors of land plants, which share a great number of similarities to charophytes and green algae as a whole. For a review of green algae, see Lewis and McCourt (2004) in this issue..

(17) Chan, C. X. & Bhattacharya, D. (2010) The Origin of Plastids. Nature Education 3(9):84 http://www.nature.com/scitable/topicpage/the-origin-of-plastids-14125758.

(18)

參考文獻

相關文件

The Tibet controversy involved confrontations of theories and believes in Lasa between a sect of Longshu Buddhism, which derived form India, and zen Buddhism from the China

“Social welfare” if defined in a narrow sense refers to the services provided by the Social Welfare Department (SWD) and Non-governmental Organisations (NGOs),

Students are asked to collect information (including materials from books, pamphlet from Environmental Protection Department...etc.) of the possible effects of pollution on our

In the context of public assessment, SBA refers to assessments administered in schools and marked by the student’s own teachers. The primary rationale for SBA in ICT is to enhance

Then, a visualization is proposed to explain how the convergent behaviors are influenced by two descent directions in merit function approach.. Based on the geometric properties

which can be used (i) to test specific assumptions about the distribution of speed and accuracy in a population of test takers and (ii) to iteratively build a structural

The temperature angular power spectrum of the primary CMB from Planck, showing a precise measurement of seven acoustic peaks, that are well fit by a simple six-parameter

The difference resulted from the co- existence of two kinds of words in Buddhist scriptures a foreign words in which di- syllabic words are dominant, and most of them are the