企鹅珍珠贝同工酶酶谱特征及其遗传分析

The pecuIiarities of zymogram and their genetic analysis in Pteria penguin

采用垂直板状聚丙烯酰胺梯度凝胶电泳分离技术,对企鹅珍珠贝闭壳肌、外套膜、鳃、消化盲囊、足组织的SOD、EST、LDH、G6PDH、MDH、ME 6种同工酶酶谱特征及其遗传控制进行了研究。6种同工酶在不同组织中的表达有明显的差异,同工酶分析共检测到18个位点,其中有16个位点具多态性,群体中,多态位点比例为88.8％,平均杂合度为0.396±0.029。有13个多态位点上的基因型频率与Hardy-Weinberg定律相符(P>0.05),位点Ldh-1、Ldh-2、Sod-2极显著偏离该平衡(P<0.01)。在G6pdh-1位点发现较高频率的无效等位基因。

The wing pearl oyster Pteria ( Magnavicula ) penguin Ridding is a kind of fast growing and large-sized bivalve species, which is distributed along the coastline of Hainan Island, Leizhou Peninsula and other waters in South China Sea. It has been identified as a candidate for bigger pearl cultivating but is not sufficiently prolific in the wild due to the depletion of its natural resources. Its hatchery techniques and the technology of producing mabe, imaging and round pearls fi'om this oyster have been developed successfully recently. In order to discern the hereditary background for future genetic breeding of this species, vertical polyacrylamide gradient gel electrophoresis was used to analyze the peculiarity and genetic control of isozymes in P. penguin. SOD, EST, MDH, ME, LDH and G6PDH from five kinds of tissues (adductor muscle, mantle, gill, digestive gland and foot) were studied. The expression peculiarities of the above 6 isozymes were distinctly varied in different tissues. 18 loci were recorded, of which, 16 loci were polymorphous. In the examined population, the rate of polymorphic loci was 88.8 %, and the average heterogeneity index was 0.396 ± 0.029. The allelic frequencies of 13 loci were accordant with the Law of Hardy - Weinberg ( P>0.05), frequencies of other 3 loci, Ldh - 1、 Ldh -2 and Sod- 2 were obviously deviated from the genetic equilibrium(P<0.01), the reason of which for Ldh-1, Ldh-2 was the deficiency of the heterozygosity, for Sod - 2 was that only hybrid present at this locus. At locus of G6pdh -1, high frequency of null gene was discovered.