采用qRT—PCR、RACE等方法,获得了拟穴青蟹丝裂原活化蛋白激酶激酶(MAPKK)基因cDNA全长序列。该基因全长1558bp,开放阅读框长度为1224bp,编码407个氨基酸残基。同源分析显示,该基因编码的蛋白与昆虫的相似性高达70%,推测MAPKK基因在节肢动物具有较高的保守性。经荧光定量PCR检测,MAPKK基因在拟穴青蟹多个组织中有表达,且在脑神经节和卵巢中表达量较高。在拟穴青蟹卵巢发育过程中,MAPKK基因在卵巢发育期(Ⅲ期)表达量最高,发育期为卵母细胞快速生长期,推测MAPKK具有促进卵母细胞快速生长的作用。
In this paper, the MAPKK (mitogen-activated protein kinase kinase)was isolated from the mud crab,Scylla paramamosain using RT-PCR and RACE methods. The obtained full-length cDNA of MAPKK was 1 558 bp with an open reading frame of 1 224 bp encoding a putative peptide of 407 amino acids. By alignment,the amino acid sequence of S. paramamosain MAPKK showed high homology with those of some other animals. It suggested MAPKK was highly conservative. Real-time PCR showed that the MAPKK gene was expressed in various tissues, and highly expressed in brain ganglion and ovary. The MAPKK mRNA profiles during ovarian development indicated that the expression of MAPKK was significantly high at developing stage. We inferred that MAPKK might play a stimulative role in the ovarian development of the mud crab.