文蛤亮氨酸氨肽酶LAP3的基因克隆及其在幼体不同发育时期、成体不同组织的表达分析

Gene cloning and expression analysis of leucine aminopeptidase LAP3 gene in different development stages of larvae and different tissues of adult of Meretrix meretrix

为探索贝类LAP3基因的结构和功能特征以及在生长发育过程中的作用,利用cDNA末端快速扩增(RACE)法获得文蛤LAP3(Mm-LAP3)基因的cDNA全长序列,并对其生物信息学、组织及发育时期表达特征进行了分析。结果显示,Mm-LAP3基因cDNA全长2 037bp,ORF区1 254bp,编码417个氨基酸;Mm-LAP3蛋白由Peptidase_M17超家族序列的N-端结构域和Peptidase_M17催化结构域组成。荧光实时定量PCR结果表明,Mm-LAP3基因在文蛤成体6个组织和幼体10个发育时期中均有表达,其中在斧足中的表达量显著高于其他组织(P<0.05),这与斧足蛋白含量丰富、代谢旺盛相关;在幼体10个发育时期中的表达量呈现逐渐升高的趋势,在D形幼虫时期达到最高,随后又有所降低,推测Mm-LAP3基因在早期发育时期参与了某些组织器官的形成。

To explore the molecular structure and functional characteristics of LAP3 gene and its role in the process of growth and development, full length cDNA of LAP3 in Meretrix meretrix （Mrn-LAP3）was cloned by rapid am plification of cDNA ends technique（RACE）, then the bioinformatics and expression profiles in different adult tis sues and developmental stages of larvae were analyzed. The results showed that the full length cDNA of Mm- LAP3 gene was 2 037 bp, containing a complete 1 254 bp ORF encoding 417 amino acids. There were two functional domains of Mm-LAP3 protein （Peptidase_M17 and N-terminal）. The result of Q-RT PCR indicated that Mm-LAP3 expressed in six tissues and ten developmental stages, but the expression of foot was significantly higher than other tissues. The expression of Mrn-LAP3 gradually increased with the process of the development, and showed the highest in D-shaped larvae stage, and then the expression decreased, which suggested that Mm-LAP3 may be involved in the formation of certain organs in early developmental stages.