嗜热四膜虫可变剪接基因鉴定及功能分析

Identification and Functional Analysis of the Alternative Splicing Genes in Tetrahymena thermophila

可变剪接是产生蛋白质组多样性和调节基因表达的重要机制,相关研究在高等真核生物中开展较多,而在单细胞真核生物中则较少,尤其是单细胞原生动物纤毛虫中,仅有少量报道。本文基于单细胞模式原生动物嗜热四膜虫种大量转录组数据,对其可变剪接基因进行了鉴定及分析。在嗜热四膜虫中共鉴定到2 894个可变剪接位点,涉及到2 698个可变剪接基因,可分为四类。考虑到转录本拼接的准确性,选择了其中464个与基因组预测模型完全一致的可变剪接基因进行深入分析,其中生长(growth)时期、饥饿(starvation)时期、接合生殖(conjugation)时期特异性的可变剪接基因分别为49个、79个和135个。对可变剪接基因的功能进行分析表明其涉及的功能广泛且显著富集于蛋白激酶过程,提示可变剪接基因在嗜热四膜虫蛋白磷酸化和信号传导中具有重要作用。

Alternative splicing（AS） is the important way to generate the protein diversity and post-translational gene expression regulation.Currently,AS studies mainly focused on the high eukaryotes,few studies have been found in the single-celled eukaryotes,especially in the ciliated protozoans.This study analyzed the AS genes in model organism Tetrahymena thermophila based on the next generation transcriptome sequencing（RNA-Seq） data.A total of 2894 splicing sites were identified in T.thermophila,represented 2 698 AS genes in four different types.Taking into account the accuracy of the transcripts/gene models,464 highly confident genes were used to further analysis.In these genes,there are 49,79 and 135 stages specific AS genes in growth,starvation and conjugation,respectively.Functional analysis showed that the AS genes involved in a wide range of biological processes,and significantly enriched in the protein kinase,which suggested that AS play an important role in the protein phosphorylation and cell signaling transduction in T.thermophila.