甘藷塊根澱粉磷解脢激脢之生化學檢定

Abstract

磷酸化是常見的蛋白質轉譯後修飾，同時也是訊息傳導中相當重要的一環。相對於動物界肝糖磷解脢 (glycogen phosphorylase, GP) 具有詳細而完整的磷酸化調控系統，植物細胞中相似度極高的澱粉磷解脢 (starch phosphorylase, SP)，卻從未有同樣的發現；直到2004年Tetlow等人才在小麥造粉體中觀察到澱粉磷解脢有被磷酸化修飾的現象 (Tetlow et al, 2004b )。本實驗室楊光華則在甘藷塊根中純化出針對L型澱粉磷解脢的激脢，並命名為澱粉磷解脢激脢 (L-SP kinase, LSK) (楊光華, 2005)。本論文承續楊光華的研究，進一步精製此激脢，並嘗試以二維電泳的方式進行解析，盼能藉以確定其身份；同時更進一步的藉由蛋白質陣列的實驗，嘗試探討此激脢與澱粉磷解脢之間的辨識關係。

Protein phosphorylation is a common post-translational modification after gene expression, and play an important role in signal transduction. In contrast to the well characterized phosphorylation regulation system to glycogen phosphorylase (GP) in animal cells, the regulation has not been reported on starch phosphorylase (SP) in plant cells. Recently, Tetlow and colleagues observed the phosphorylation of SP in the amyloplast of wheat (Tetlow et al, 2004). In our labortory, Young has purified the specific kinase for the L-form starch phosphorylase (LSK) (Young, 2005). In this study, we have tried to purify LSK-S300, and analyze its identity by two-dimensional electrophoresis. Furthermore, the combination of LSK to its substrate L-SP was performed by peptide array experiment to elucidate the site specific binding of these two proteins.