Genetic mechanism in hybrid sterility of the mouse

小鼠杂交不育的遗传机制

基本信息

批准号：
05680746
负责人：
MATSUDA Yoichi
金额：
$ 1.34万
依托单位：
National institute of Radiological Sciences
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1994
项目状态：
已结题

项目摘要

In our initial sutdies (1992) we observed high frequency of X-Y dissociation (X//Y) at first meiotic metaphase (MI) in sterile (C57BL/6 X M.spretus) F_1 males, and that in the backcross progeny the X//Y trait segregated as a single gene which was linked to a distal locus on the X chromosome, Amg. To examine the role of pseudoautosomal region (PAR) in X-Y pairing and male feritility we produced congenic lines that carried the spretus PAR on the C57BL/6 (B6) background or the converse of B6 PAR onto the spretus host. The progeny with either high X//Y and small testis size or low X//Y and large testis size segregated almost 1 : 1 in each succeeding backcross generation, and the bimodal distribution was completely correlated with the segregation of the distal X chromosome gene marker, TeloXY.Furthermore, fertile progeny with low X//Y and homozygous PAR-type were found in mating M.spretus males with female miece of the congenic line, this result showing that the genetic divergence of PAR is … More a major contribution to the male sterility observed in interspecific hybrid males.Spermatogenesis is arrested in earlier stage of primary spermatocytes and any first meiotic metaphase are not observed in (B6 X M.macedonicus) F_1 males. To examine genetic mechanism of male sterility in the hybrid, we examined X-Y dissociation and sterility in backcross males from fertile F1 females crossed with C57BL/10. Three types of progeny were found as follows : progeny with no MI and small testis size, high X-Y dissociation and small testis size, and low X-Y dissociation and large testis size. This result indicates that there are one or two autosomal factors, which controls hybrid sterility, in addition to the pseudoautosomal region.Chromosomal segregation was analyzed in 80 (B6 X M.spretus) F_1 X M.spretus progeny and 70 (B6 X M.spretus) F_1 X B6 progeny using FISH analysis with a major satellite DNA probe (pMR196). The results suggested that there was not primary deviation from random assortment during meiosis in the interspecific hybrid female, because nearly all of the 190 pair-wise comparisons did not deviate from expected and because there was no consistent pattern of deviation of the same chromosomes in the reciprocal backcross progeny from similar (C57BL/6 X M.spretus) F_1 hybrid females. Less

In our initial sutdies (1992) we observed high frequency of X-Y dissociation (X//Y) at first meiotic metaphase (MI) in sterile (C57BL/6 X M.spretus) F_1 males, and that in the backcross progressy the X//Y trait segregated as a single gene which was linked to a distal locus on the X chromosome, Amg.为了检查假射量最高区域（PAR）在X-Y配对和男性生育能力中的作用，我们产生了同类线，这些线路在C57BL/6（B6）背景或B6 PAR的Converse上携带Spretus Par或B6 PAR的相反。在每个依次的背部产生中，具有较高x // y和较小的睾丸大小或较小的睾丸大小或较小的睾丸大小和较大的睾丸大小的后代在几乎隔离1：1，双峰分布与远端x染色体基因标记物的远端x染色体基因，静脉texy.furtherthermorore m.parepers pare-x/y/y y y/y/y y y/y y y y/y/y/y y y y y/y y y y/y y y/y y y y y y y y/y y y/y y y y y y y y y m。男性患有女性MIE的良性线，这一结果表明，PAR的遗传差异是对在种间杂交雄性中观察到的男性不育的主要贡献。在初级的精子细胞的早期阶段被捕。为了检查杂种中男性不育的遗传机制，我们检查了与C57BL/10交叉的肥沃F1雌性的反向交叉雄性中的X-Y解离和无菌性。发现三种类型的后代如下：没有MI和小睾丸大小的后代，X-Y分离较高，睾丸尺寸较小，X-Y解离较低和大睾丸大小。该结果表明，除了假毒素区域外，还有一个或两个常染色体因素控制杂交不育。（PMR196）。结果表明，种间杂交女性的减数分裂过程中的随机分类并没有主要偏离，因为几乎所有190对的对比较都没有偏离预期，并且因为在相似的后代中，相同的后骨中相同的染色体没有一致的（C57BL/6 x x m.ssprets forme forment）fembret forem forem forem forem forem forem forem forepross。较少的