基于RNA-seq数据分析长牡蛎(Crassostrea gigas)天然免疫的可变剪接事件

ANALYSIS OF ALTERNATIVE SPLICING EVENTS FOR INNATE IMMUNITY OF CRASSOSTREA GIGAS INDUCED BASED ON RNA-SEQ

大部分无脊椎动物缺乏基于经典抗体和记忆细胞的适应性免疫,因而天然免疫在无脊椎动物免疫防御中发挥不可或缺的作用。可变剪接正是产生天然免疫多样性和特异性的重要途径。牡蛎(Crassostrea)是全球范围内的大宗养殖贝类和我国产量最高的海水养殖贝类,理解其天然免疫系统的多样性和特异性对牡蛎病害防治和养殖业健康可持续发展至关重要。通过对不同病原诱导以及诱导后不同时间的转录组进行生物信息分析,系统地研究了长牡蛎天然免疫应激反应的可变剪接事件。发现在弧菌诱导下可变剪接事件的总数显著增加,表明弧菌的感染会诱导长牡蛎可变剪接事件的产生。对病原诱导后可变剪接体的组成类型及表达量显著变化的基因的功能富集分析,表明免疫系统相关功能被显著富集,病原感染不同阶段以及不同病原感染后可变剪接体的组成类型和表达量均不一致,表明长牡蛎免疫系统可通过可变剪接产生免疫响应的特异性和多样性。研究结果为长牡蛎等无脊椎动物天然免疫多样性和特异性提供了典型实例,也为长牡蛎病害防御提供了理论支撑。

Most invertebrates lack adaptive immunity based on classical antibodies and memory cells,thus natural immunity plays an indispensable role in invertebrate immune defense.Variable splicing is an important way to generate diversity and specificity of natural immunity.Crassostrea is a globally farmed shellfish and the most productive marine shellfish in China.Understanding the diversity and specificity of its natural immune system is essential for the prevention and control of oyster diseases and the sustainable development of oyster aquaculture.The variable splicing events in the natural immune stress response of Crassostrea gigas were investigated systematically by bioinformatic analysis of transcriptomes induced by different pathogens at different times after induction.The total number of variable splicing events was found to increase significantly under Vibrio induction,indicating that Vibrio infection induced the generation of variable splicing events in C.gigas.Functional enrichment analysis of genes with significant changes in the composition type and expression of variable spliceosomes after pathogen induction showed that immune system-related functions were significantly enriched,and that the composition type and expression of variable spliceosomes were inconsistent at different stages of pathogen infection as well as after different pathogen infections,suggesting that the immune system of the long oyster can generate specificity and diversity of immune responses through variable splicing.This study provided a typical example of the diversity and specificity of natural immunity in invertebrates such as C.gigas,and also a theoretical support for the defense of C.gigas diseases.