马氏珠母贝Perlucin基因序列特征及其SNP与耐低温性状的关系OACHSSCDCSTPCD

[Objective]The aim of this study is to clone a new lectin molecular gene,named Perlucin,from Pinctada fucata martensii,and to study its expression under low-temperature stress and its SNPs associated with low-temperature resistance traits.[Method]According to the sequence of Perlucin in the genome of P.f.martensii,primers were designed to clone the full length of Perlucin.The structure and physicochemical characteristics of Perlucin was analyzed by bioinformatics methods.The low-temperature stress(17℃)experiment(22℃as the control)was conducted on P.f.martensii,and the expression of Perlucin under low-temperature stress was detected by Quantitative-PCR.SNP loci and haplotypes in the Perlucin exon region of the low temperature resistant line(R)and Beibu Gulf wild population(W)were screened and compared.[Result]Sequence analysis revealed that the full length of Perlucin is 631bp that encoded 152 amino acids and contained 1 signal peptide and 1 C-type lectin domain.Homologous analysis showed that Perlucin was most closely related to Mytilus galloprovincialis.Perlucin showed highest expression in the gill,followed by the foot and hepatopancrea.Under the low temperature stress(17℃),the expression of Perlucin firstly increased and then decreased.The highest expression level at 12 h,significantly higher than that in the control group(22℃),indicated that Perlucin may participate in the cryogenic response process of P.f.martensii.The SNPs of the exon region of perlucin were analyzed,and a total of 30 SNPs were obtained,among which the genotype frequencies of 13 SNP loci varied significantly between R and W populations(P<0.05).[Conclusion]Perlucin is a candidate gene involved in the low-temperature adaptation of P.f.martensii.Two SNP loci were screened(g.40078856 and g.40078945).