龙须菜UDP-葡萄糖焦磷酸化酶基因的克隆及其表达与琼胶产量的关系

摘要

对红藻龙须菜(Gracilaria leimanei formis)UDP葡萄糖焦磷酸化酶(UGPase)基因的表达与不同藻株中藻体琼胶产量之间的相关性进行研究.通过PCR扩增的方法得到了龙须菜UGPase的基因序列.该基因cDNA序列的全长为2 200 bp,开放阅读框1 485 bp,编码494个氨基酸;龙须菜UGPase基因的氨基酸序列与其它物种的UGPase氨基酸序列相似性较高;该基因是单拷贝的,缺乏内含子;具有特殊的加尾信号.利用荧光实时定量PCR的方法检测UGPase基因相对表达量.结果表明,该基因的表达与琼胶含量存在显著相关性,即在高琼胶组藻株中的表达量显著高于低琼胶组藻株,对琼胶含量高低具有指示作用,显示了在产业化应用中的潜能.%The purpose of the study is to investigate the relationship between gene expression level of UDP-glucose pyrophosphorylase (UGPase) and the agar content in red algae Gracilaria leimaneiformis.PCR was employed to obtain the gene sequence, which gave out a cDNA of 2200 bp, coding for 494 amino acids, involving 1485 bp of ORF. The deduced amino acid sequence showed significant similarity to the UGPase sequences of other species. The gene is single-copy, devoiding of introns, and has special polyA tailing signal. Real time quantitative PCR technique was used to detect the relative expression level of UGPase, which revealed a highly correlation between UGPase gene expression level and agar contents.The expression level of UGPase gene in high agar content strains is significantly higher than those in low,which may be applied in indication of agar content and further algal cultivation.