茯苓表現序列基因庫之建構與分析

Abstract

茯苓是一種在中藥方劑裡應用範圍最廣的真菌，因其具有抗腫瘤與增進免疫力的功能。然而，其生物活性成份有關知識仍有限，且基因體研究尚在起步階段。因此，本研究欲自茯苓菌絲體建立一個茯苓表現序列標誌(EST)基因庫，並從中尋找未來具有醫藥應用潛力的蛋白質。在分析液態培養茯苓菌絲體EST 基因庫的過程中，我們發現其16％的基因參與代謝作用、21％的基因參與遺傳訊息傳遞（其中10％為核醣體蛋白基因）、7％的基因參與環境訊息傳遞、3%的基因參與細胞程序、53％為未知功能的基因。此外，有一個與樟芝免疫調節蛋白Aca1胺基酸序列相似度達50％的基因(WcFIP1)，推測此蛋白質可能是一種茯苓免疫調節蛋白。

Wolfiporia cocos is the most popular fungal ingredient in Chinese prescription because it functions in arresting the growth of tumer cells or stimulating immune systems. Nevertheless, knowledge regarding to its bioactive compounds and genomic information are limited. Thus, we would like to establish an expressed sequence tag (EST) library from Wolfiporia cocos and explore candidates with pharmaceutical potentials in this study. Characterization of Wolfiporia EST library reveal that 16%, 21%, 7% and 3% of genes are participating in metabolism, genetic information process, environmental information process, cellular process, respectively. 53% of those are unknown genes. Furthermore, a gene encodes a protein sharing 50% sequence similarity to Taiwanofungus camphorate fungal immunomodulatory protein (Aca1), and is therefore named as WcFIP1. We hypothesize that the newly isolated WcFIP1 might be one of the fungal immunomodulatory proteins in Wolfiporia cocos.