摘要
成熟促进因子（MPF）是诱导细胞从G2期转入M期的关键因子，在配子成熟过程中具有重要作用．MPF由周期蛋白B（cyelin13，CB）和周期蛋白依赖性蛋白激酶（cDKl，由cdc2基因编码）2个亚基组成．本研究克隆了大黄鱼（Larim-ichthyscrocea）cyclinB1（Lc-cbl）和cdc2（Lc-cdc2）基因的eDNA序列，并分析了这2个基因mRNA的组织表达特征．为解析MPF在大黄鱼性腺发育和配子成熟的作用机理奠定基础．Lc-cbl基因全长cDNA1882bp，可编码397个氨基酸的蛋白；Lc-cdc2基因全长eDNA序列1151bp，可编码303个氨基酸的蛋白．基于Lc-cblcDNA序列推导的氨基酸序列与6种脊椎动物的CBl氨基酸序列有较高相似性（67％～84％），并具有周期蛋白盒、毁坏盒、以及蛋白酶K位点（RRxSK）等CB预期特征．基于Lc-cdc2的eDNA序列推导的氨基酸序列也与其他6种鱼类的CDKl氨酸酸序列有较高相似性（88％～97％），并具有丝氨酸／苏氨酸激酶催化结构域、ATP结合相关的保守序列（GxGxxGxV）、周期蛋白结合相关的PSTAIRE序列等CDKl的预期特征．可见，本研究克隆获得的2条序列是Lc-cbl和Lc-cdc2eDNA全长．实时荧光定量PCR结果显示，Lc-cbl和Lc-cdc2的2个基因mRNA表达具有相似的组织特异性，在性腺中tuRNA水平均远远高于其他组织，表明Lc-c6J和Lc-cdc2是大黄鱼性腺发育相关的重要基因．
Mature promoting factor(MPF),a complex composing of cyclin B and cyclin-dependent kinase(CDK1,encoded by cdc2 gene),is the key factor to stimulate cells entrancing M phase from G2phase.MPF was found playing an important role in maturation process of gamete.To better understand the molecular mechanism of gamete maturation of large yellow croaker(Larimichthys crocea),the full length cDNA of cdc2(Lc-cdc2)and cyclin B1(Lc-cb1)were cloned and characterized.The full length cDNA of Lc-cb1 is 1 882bp,encoding aprotein of 397amino acids;and the full length cDNA of Lc-cdc2 gene is 1 151bp,encoding aprotein of 303 amino acids.The deduced amino acid sequence of LC-CB1shared high similarity with those of other six vertebrates(67%-84%),and composed of the expected conserve domains and motifs of CB1,such as a cyclin box,a specific destruction box(RxALGxIxN),and the B-type cyclin characterized proteinase K sites(RRxSK).Similarly,the deduced amino acid sequence of LC-CDK1also shared high similarity with those of other six fish species(88%-97%),and composed of the expected conserve domains and motifs of CDK1,such as a serine/threonine kinase catalytic domain,the conserved sequence GxGxxGxV related to ATP-binding,PSTAIRE sequences for binding cyclin B.In addition,the mRNA levels of LC-cb1 and LC-cdc2in the gonad were both much higher than those in other tissues(p<0.05),indicating that Lc-cb1 and Lc-cdc2 may play essential roles in the oogenesis and spermatogenesis of large yellow croaker.
出处
《厦门大学学报（自然科学版）》
CAS
CSCD
北大核心
2014年第1期132-141,共10页
Journal of Xiamen University：Natural Science
基金
国家自然科学基金(31272653)
福建省农业科技重点项目(2013N0024)
集美大学创新团队基金(2010A001)
