马氏珠母贝中类胡萝卜素总含量差异表达基因的转录组分析

Transcriptome analysis differentially expressed genes with total carotenoid contents in pearl oyster(Pinctada fucata martensii)

对马氏珠母贝黑壳色选育系高(HC)和低(LC)总类胡萝卜素含量(TCC)个体之间进行转录组的差异表达基因(DEGs)分析,利用qRT-PCR对候选基因进行验证,运用靶向重测序技术鉴定候选基因PmSR-BI的SNPs,并进行TCC与PmSR-BI中SNPs的关联分析。结果显示,HC组和LC组之间共鉴定了1025个DEGs,其中HC组PmSR-BI的表达水平显著高于LC组(P<0.05);PmSR-BI SNP位点鉴定分析发现,外显子中有7个SNPs,在5´调节区发现8个SNPs;关联分析显示,外显子中的1个SNP和5´调节区的两个SNP与TCC显著相关(P<0.05)。单倍型分析发现,PmSR-BI的SNPs含有四个单倍块,单倍块1中的CC单倍型和单倍块3中的AG单倍型显著高于其他单倍型。研究结果有助于阐明类胡萝卜素代谢的机制,并促进马氏珠母贝高含量类胡萝卜素个体选育进程。

Differentially expressed genes(DEGs)between individuals with high(HC)and low(LC)total carotenoid content(TCC)were sampled from a selected line of Pinctada fucata martensii with black shell in the prismatic layer.The expression levels of candidate genes were verified by qRT-PCR.Targeted resequencing was used to detect SNPs in a candidate gene,PmSR-BI.The association of TCC with SNPs in PmSR-BI was determined.Results showed that a total of 1025 DEGs were identified between HC and LC.The expression levels of the candidate gene PmSR-BI in HC were higher than those in LC.Seven SNPs in the exon and eight SNPs in the 5′regulatory regions of PmSR-BI were found.Association analysis showed that one SNP in the exon and two SNPs in the 5′regulatory regions of PmSR-BI were significantly associated with the TCC(P<0.05).All SNPs of PmSR-BI were divided into four blocks.CC haplotype in Block 1 and AG haplotype in Block 3 were significantly higher than other haplotypes.These results help elucidate the mechanism underlying carotenoid metabolism and develop marker-assisted breeding design in the species.