牡丹江水系钝吻细鳞鲑的同工酶

Isozyme of Brachymystax tumensis in Mudanjiang River

采用聚丙烯酰胺凝胶垂直板电泳方法，对牡丹江水系钝吻细鳞鲑（Brachymystax tumensis）的眼、性腺、心、肾、肝、肌肉6种组织中的12种同工酶LDH、MDH、G6PDH、EST、POD、ME、SOD、α-AMY、CAT、COX、SDH和FDH进行了电泳研究，结果显示：钝吻细鳞鲑同工酶表现出明显的组织特异性；群体遗传多样性研究共记录出20个基因座位，其中9个基因座位Est-1、Est-4、Est-5、G6pdh-2、Gdh-1、IAh-1、Sdh-1、Sdh-2、Sod-2表现为多态。钝吻细鳞鲑的多态座位比例（P=45％）在鱼类中居较高水平，平均预期杂舍度（He=0.2243）、平均实际杂合度（Ho=0.6540）也较高，偏离了Hardy-Weinberg平衡，证明钝吻细鳞鲑可能存在较高程度的非平衡选择。从钝吻细鳞鲑群体的遗传偏离指数（d=1.9153）可以看出，其杂合子高度过剩，位点有效等位基因数（Ne=1.45）在目前已见报道的硬骨鱼类多样性研究中（Ne=1.16-1.58）处于上限值，即遗传多样性水平较高。从研究得到的数据可以看出，牡丹江水系的钝吻细鳞鲑的种质杂合度较高。

The expression patterns of twelve isozymie systems （ LDH, MDH, G6PDH, EST, POD, ME, SOD, α-AMY, CAT, COX, SDH,FDH） in 6 different tissues （eye, sex gland, heart, kidney, liver and muscle） of Brachymystax tumensis were studied by using the vertical polyacrylamide gel electrophoresis. Specific expression pattern was apparently found in the twelve isozymes in B. tumensis. The eleetrophoretie patterns of 8 isozymes showed that there were 20 genetic loci, and Est-1, Est-4, Est-5, C6pdh-2, Gdh-1, Ldh-1, Sdh-1, Sdh-2, Sod-2 were polymorphie loci. The average percentages of polymorphic loci of B. tumensis was very high （45%）, and the average expected heterozygosity per locus （0.2243） and the average observed heterozygosity （0. 634 O） were also relatively high. It was not in Hardy-Weinberg equilibrium, which proved that the family of B. tumensis suffered a highly unbalanced natural choice. Thegenetie departure index of B. tumensis （ d = 1.9153 ） showed that the heterozygosity was excessive. Alleles per locus （ Ne=1.45 ） were high, indicating that the gene diversity of B.tumensis was rich. The quality of B. tumensis in Mudanjiang River was mixed.