红鳍东方鲀6种同工酶的组织特异性及基因位点分析

采用水平淀粉凝胶和聚丙烯酰胺凝胶垂直电泳法,对2龄野生红鳍东方鲀的肌肉、肝脏、肾脏、心脏、眼、鳃6种组织中的苹果酸酶(ME),乳酸脱氢酶(LDH),异柠檬酸脱氢酶(IDH),葡萄糖脱氢酶(GLCDH),磷酸葡萄糖变位酶(PGM)和酯酶(EST)共6种同工酶进行了研究。结果表明,以上6种同工酶存在明显的组织特异性。LDH在除肝脏外的5种组织中活性很强,GLCDH只在肝脏中表达,鳃组织中的GLCDH和肌肉组织中的EST表达活性都很弱。6种同工酶共检测到12个基因位点,其中ME和PGM有两个基因位点编码,EST有5个基因位点编码。本试验还检测到Ldh-1、Est-1、Est-2、Est-3和Est-4共5个基因位点具有多态现象(P0·99),多态位点比例为41·67%,在12个基因位点共观察到17个等位基因表达,平均每个位点表达的等位基因数为1·417个。同时在红鳍东方鲀眼组织中发现,AB3型和B4型LDH间有一条酶带弱表达。

Tissues specificity and loci analysis on six isozymes of Takifugu rubripes

Six isozymes in muscle, liver, kidney, heart, eye and gill of Takifugu rubripes were analyzed with horizontal starch gel electrophoresis and vertical polyacrylamide gel electrophoresis. The results showed that each isozyme manifested different expressions in the six tissues. LDH exhibited very high activities in all tissues except for liver, while GLCDH expressed only in liver. The activities of GLCDH expressed in gill and of EST expressed in muscle were lower than those in other tissues. Twelve gene loci, including five polymorphic loci, i. e. Ldh-1 Est-1,Est-2,Est-3 and Est-4, were observed in this wild Takifugu rubripes population. The isozymes of LDH,IDH and GLCDH were coded by one gene locus, while ME and GLCDH were coded by two gene loci. The expression of EST was the most complicated among the six isozymes examined, since it was coded by five gene loci. The proportion of polymorphic loci was 41.67%. Altogether seventeen alleles were observed in 12 loci, the mean number of alleles perlocus being 1.417. A weak LDH-band was found in the eye tissue of Takifugu rubripes between B4 and AB3.