仿刺参昼夜节律相关基因的筛查和表达分析

Screening and expression analysis of circadian rhythm genes in Apostichopus japonicus

为研究仿刺参昼伏夜出行为节律的内源性调控机制,需要先筛查出仿刺参是否具有能够调控生物节律的生物钟基因。本研究通过Blastp,将KEGG数据库中哺乳动物和果蝇的昼夜节律通路成员基因与仿刺参全基因组进行同源比对,筛选仿刺参基因组中的同源生物钟基因,并参考不同光照条件下仿刺参触手转录本数据,对相关基因在不同光照条件下的表达量进行初步分析。结果显示,在仿刺参全基因组中找到了绝大部分具有较好注释的同源候选生物钟基因,包括CLOCK(Circadian Locomotor Output Cycles Kaput)、BMAL1(Brain and Muscle Arnt-Like 1)/CYC(Cycle)、TIM(timeless)等,但PER(Period)和DEC(class B basic helix-loop-helix protein 2/3)基因未能匹配到有效的同源基因;转录本的数据表明,在120 lx光照1 h与120 lx光照5 min比较组中(Lt1h:Lt5m),发现只有CLOCK基因具有显著的下调表达(log_(2)FC=-1.1209),其他生物钟基因如BMAL1/CYC和TIM,虽然不具有显著表达差异,但仍然具有下调表达的趋势,而相关基因的下调表达具有减弱生物活动的效应。上述结果表明仿刺参存在昼夜节律的基因调控基础,借助转录本数据初步表明光照可能具有扰乱仿刺参行为节律的效应,但仍需深入研究。

It is necessary to screen whether the apostichopus japonicus has the biological clock genes to regulate the biological rhythm,which can reveal the endogenous regulation mechanism of the circadian rhythm.In this study,the genes of the circadian rhythm pathway of mammal and fruit fly in the KEGG database were blasted with the whole genome of A.japonicus,and screened the homologous biological clock genes.Based on the tentacles transcriptomes,the expressions of related genes was preliminarily analyzed under the different light conditions.The results showed that most of the homologous candidates,including CLOCK,BMAL1/CYC,and TIM,were found in the whole genome of A.japonicus,while the PER and DEC genes were failed to match valid homologous genes.The transcriptomes showed that only the CLOCK gene was found to have significantly down-regulated expression(log_(2)FC=-1.1209)in the comparison group of 120 lx illumination for 1 h and 120 lx illumination for 5 min(Lt1 h:Lt5 m).Other biological clock genes,such as BMAL1/CYC and TIM,were still showed a down-regulate tendency,and the down-regulated expression of related genes usually have the effect of attenuating biological activity.The above results indicated that there was a gene regulation basis for circadian rhythm works in A.japonicus.The transcriptomes showed that the light had the effect of disturbing the behavior rhythm of A.japonicus,but further researches was still needed.