栉孔扇贝FTZ-F1基因的序列特征及表达分析

Sequence characteristics and expression analysis of FTZ-F1 gene in Chlamys farreri

为研究栉孔扇贝(Chlamys farreri)FTZ-F1基因功能,对其序列特征和表达模式进行了分析。结果显示,该基因编码序列(coding sequences,CDS)长1668bp,编码555个氨基酸,含DBD(DNA binding domain)保守区、FTZ-F1盒(FTZ-F1 box)、LBD(ligand binding domain)保守区,其保守区与其他物种较为一致。采用半定量PCR(RT-PCR)和荧光定量PCR(qRT-PCR)方法检测了FTZ-F1基因在栉孔扇贝中的表达,发现在雌性栉孔扇贝的闭壳肌、肾、鳃组织和雄性栉孔扇贝的精巢、肝胰腺、闭壳肌、肾中表达较强,在其他组织中表达较弱;在性腺发育周期中,FTZ-F1基因主要在成熟期精巢中表达,表达量显著高于其他时期性腺,表明FTZ-F1基因主要在成熟期精巢中发挥重要作用,推测可能与成熟期精巢睾酮含量升高相关。

Through sequence characteristics and expression pattern analysis of FTZ-F1 gene in Chlamys farreri,this study speculated FTZ-F1 function in Chlamys farreri.The gene could not be exactly classified only by systematic evolution analysis,so sequence and expression characteristics analysis were combined,finally it was named FTZ-F1.The FTZ-F1 sequence analysis showed that the CDS(coding sequences)was 1668 bp long,encoding 555 amino acids,including DBD(DNA binding domain)conserved region,FTZ-F1 box(FTZ-F1 box),LBD(ligand binding domain)conserved region.Multiple sequence alignment results of different species showed that conserved region of the gene was consistent with other species.The expression of FTZ-F1 in Chlamys farreri was studied by semi quantitative PCR(RT-PCR)and quantitative real-time PCR(qRT-PCR).It showed that FTZ-F1 expression was stronger in female adductor muscle,kidney,and gill tissue,as well as the male testis,hepatopancreas,adductor muscle and kidney,the expression also existed weakly in female mantle,hepatopancreas,ovarian tissues and the male gill,mantle,the wide range of tissue expression indicated that the gene function in Chlamys farreri may be more extensive.And because the gene was expressed in gonads and liver of Chlamys farreri,we speculated that the FTZ-F1 tissue expression pattern in Chlamys farreri had the expression characteristics of NR5A2(LRH-1/FTF)and SF-1/Ad4BP subgroup at the same time.Further study found that FTZ-F1 expressed strongly in the testis of Chlamys farreri,so its expression characteristics were believed to be more biased towards the SF-1 subgroup.The reproductive cycle of Chlamys farreri mainly included proliferation stage,growing stage and mature stage,using quantitative real-time PCR,the FTZ-F1 expression was detected in ovary and testis during the reproductive cycle.The result showed that the expression of FTZ-F1 had no significant change during the entire gonadal developmental period in ovary,but had changed during gonadal developmental in testis.At the proliferation and growth stages,there was no significant difference of FTZ-F1 expression in testis(P>0.05),while there was a significant increase(P<0.05)at the mature stage in testis,the expression in mature testis was not only significantly higher than that of the other stages,but also higher than expression in ovaries during the whole gonadal development.This study suggests that FTZ-F1 plays an important role in testis at mature stage,it is speculated that FTZ-F1 may be related to the increase of testosterone content.