探討人類珍珠素蛋白多醣第五片段促進神經纖維生長之作用
Studies of the effect of human perlecan domain V on promoting neurite outgrowth
中文摘要
基底膜(basement membrane, BM)是由第四型膠原蛋白(type IV collagen)、層黏蛋白 (laminin)及蛋白多醣(proteoglycan)等物質所構成，主要功能是扮演維持上皮及內皮細胞型 態與細胞附著及做為細胞生長支架(scaffold)的功能。硫酸肝素蛋白多醣(HSPG)為 BM 中重要 的蛋白多醣類。先前研究指出HSPG 具有促進神經纖維生長的功能，而珍珠素(perlecan)即屬 於HSPG 的一種，本研究是在探討基底膜中硫酸肝素蛋白多醣(heparan sulfate
proteoglycan)珍珠素(perlecan)在神經系統所扮演的角色與功能，先前的研究中證實重組的 人類珍珠素蛋白多醣第五片段(human perlecan domain V; H.Pln DV)在以 laminin 為基材 貼覆的環境下具有促進背根神經節神經纖維生長的能力，因此本實驗主要目的是以重組基因技 術(recombinant DNA technology)將 perlecan domain V 分成兩個含類似組成的片段 (H.Pln DV-I, H.Pln DV-II)探討其對神經纖維生長之影響及作用機轉，研究結果顯示兩片段都 會促進神經纖維的生長，先前文獻中顯示perlecan 會與乙醯膽鹼酯酵素(AchE)有交互作用且 AchE 有促進神經纖維生長之作用，本研究第二部分探討 perlecan 與 AchE 的作用是否是透過 perlecan domain V。結果顯示 H.Pln DV, DV-I, DV-II 可直接與 AchE 結合。推測 H.Pln DV 可能藉由與AchE 的結合促進神經纖維的生長的。
英文摘要
The major components of basement membrane (BM) are type IV collagen, laminin and proteoglycans. The basement membrane fuctions as a scaffold to maintain the morphology of epithelium and endothelial cells. The major type of proteoglycan in BM is heparan sulfate proteoglycan (HSPG). Previous study has shown that HSPG can promote the neurite outgrowth. Our studies are to understand the role of perlecan, which is the predominant HSPG in BM in the neurite outgrowth. Our previous study showed that recomibnant human perlecan domain V could promote the neurite
outgrowth of dorsal root ganglion (DRG) neurons in laminin coating. Here we divided the perlecan domain V (H.Pln DV) into two smaller fragment to identify the minimum fragment required for promoting the neurite outgrowth. The result showed that both of these two smaller fragments derived from perlecan domain V could promote the neurite outgrowth of DRG neurons. Previously study showed that perlecan and acetylcholinesterase (AchE) could interact with each other and AchE could promote the neurite outgrowth. Our further studies showed that H.Pln DV, H.Pln DV-I, H.Pln DV-II could bind to AchE. It suggests that H.Pln DV promoting the neurite outgrowth may be mediated by binding to AchE.
