拟穴青蟹(Scylla paramamosain)PP2A调节亚基B的基因克隆与表达分析

采用RT-PCR、RACE等方法,获得了拟穴青蟹PP2A调节亚基B(PP2A-B)的cDNA全序列,全长2040bp,开放阅读框(ORF)为1332bp,可编码443个氨基酸残基。同源分析显示,该基因编码的蛋白与其它一些物种具有很高相似性,推测PP2A-B基因具有很高的保守性。经荧光定量PCR检测,PP2A-B基因在拟穴青蟹多个组织中有表达,且在脑、卵巢、鳃中表达量较高。在拟穴青蟹卵巢发育过程中,PP2A-B基因在卵巢未发育期(I期)表达量最高,此后各期逐渐下降,推测PP2A-B在卵巢中可能以PP2A全酶的形式存在,抑制卵巢发育。

CLONING AND EXPRESSION ANALYSIS OF THE REGULATORY SUBUNIT B GENE OF PP2A IN THE MUD CRAB SCYLLA PARAMAMOSAIN

In this paper, the regulatory subunit B geneof PP2A (PP2A-B) was isolated from the mud crab, Scylla paramamosain using RT-PCR and RACE methods. The obtained full-length cDNA of PP2A-B was 2040bp with an open reading frame of 1332bp encoding a putative peptide of 443 amino acid. By alignment, the amino acid sequence of S. paramamosain PP2A-B showed high homology with those of some other animals. It suggested PP2A-B was highly conservative. Real-time PCR showed that the PP2A-B gene was expressed in various tissues, and highly expressed in brain, ovary and gill. The PP2A-B mRNA expression during ovarian development indicated that the expression of PP2A-B was obviously high at undeveloped stage and decreased gradually from stage I (undeveloped stage) to stage V (ripe stage). We hypothesized that PP2A-B may exist in the form of PP2A holoenzyme in ovary and play a suppressive role on the ovarian development of the mud crab.