俄罗斯鲟雌核发育诱导及其后代的微卫星分析

Microsatellite Marker Analysis of Gynogenesis by Induction in Russian Sturgeon(Acipenser gueldenstaedtii)

通过冷休克和热休克法诱导2组俄罗斯鲟Acipenser gueldenstaedtii雌核发育,分别获得俄罗斯鲟的冷休克雌核发育组M1和热休克雌核发育组M2。利用6对具有高多态性的微卫星分子标记,分别对雌核发育系M1中的20尾鱼苗、M2中的40尾鱼苗、双亲及对照组20尾鱼苗基因组进行PCR扩增,并对结果进行基因型分析。分别得到2个雌核发育家系的期望杂合度(He)、等位基因数(A)和等位基因频率(P)。结果表明:冷休克雌核发育组的平均期望杂合度为0.591,平均等位基因数为6.0,等位基因频率为0.010～0.708;热休克雌核发育组的平均期望杂合度为0.687,平均等位基因数为5.5,等位基因频率为0.006～0.774。以父本特异微卫星条带作为诊断性标记,对雌核发育后代进行鉴定,结果发现在冷休克组和热休克组中分别存在40%和27.5%的杂交后代,此结果与表型鉴定结果相一致。另外,与母本基因型相比较,发现在冷休克组和热休克组中分别存在10%和15%的单倍体个体。只在热休克组中发现了完全的雌核发育后代,占总数的22.5%。冷休克和热休克雌核发育家系中除了单倍体后代,杂交后代和完全雌核发育后代外,还发现了不同程度的基因重组后代。

Gynogenesis is the production of an embryo from an egg after penetration by a spermatozoon that does not contribute genetic material. The process of gynogenesis involves two steps： firstly, the sperm is inactivated by UV irradiation; secondly, the meiotic diploids are made by restraint of the extru- sion of the secondary polar body. Gynogenesis was induced in two groups of Russian sturgeon （Acipenser gueldenstaedtii） by cool shock and heat shock respectively. Cool shock （M1） and heat shock （M2） gy- nogensis offspring were gained separately. Six polymorphic microsatellite markers were used to investigate genotype by PCR amplification. Twenty fries in each group including gynogenetic families M1 , control group and their parents and forty fries in gynogenetic families M2 were chose to be analyzed . The aver- age expected heteroaygosity （He ）, allele number （A） and allele frequencies （P） in the cool shock line was 0. 591,6. 0 and 0. 100 -0. 708 respectively. In the heat shock line, the average expected heteroay- gosity, allele number and allele frequencies was 0. 687, 5.5 and 0. 006 - 0. 774 respectively. Special microsatellite bands of male parent were used as diagnostic markers to analyze the hybrid of gynogenesis offspring. The results showed that d0 % in cool shock genogenesis offspring and 27.5% in heat shock ge- nogenesis offspring were hybrid respectively. And, it is consistent with phenotypic identification results. Haploid individuals were identified in 10% of cook shock group and 15% of heat shock group. Complete gynogenetic progenies were found only in heat shock group, and they were just about 22.5%. Gene re- combination in different levels were found in other offspring except haploid, hybrid and gynogenisis off- spring of two gynogenetic lines.