Dmc1 fluorescent foci in prophase I nuclei of diploid, triploid and hybrid lilies
Dmc1 fluorescent foci in prophase I nuclei of diploid, triploid and hybrid lilies
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DOI：
10.1007/s00412-002-0193-5
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发表时间：
2002-07
期刊：
影响因子：
1.6
通讯作者：
S. George;Pearl Behl;Rhoda deGuzman;Maria Lee;Stefan Rusyniak;Y. Hotta;K. Hiratsuka;H. Takase;C. Hasenkampf
中科院分区：
文献类型：
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作者：
S. George;Pearl Behl;Rhoda deGuzman;Maria Lee;Stefan Rusyniak;Y. Hotta;K. Hiratsuka;H. Takase;C. Hasenkampf
我们检测了百合正常二倍体、三倍体和二倍体杂交种Dmc1蛋白减数分裂表位的分布。三倍体有一组额外的染色体；所有三个轴都对齐，但三个轴中只有两个在给定位置紧密配对。我们对三倍体的研究结果支持了这样一种观点，即在长周期阶段保持病灶需要成功的同源性检查和突触复合体（SC）的起始；三倍体的病灶数量从早期的合子期到粗线期减少了约30%，三倍体的粗线期值与二倍体的粗线期值相似。物种杂交缺乏染色体同源性，SC形成减少，相互遗传交换少。在本种杂交种中，合子期早期的灶数与正常二倍体相似，但在合子期中期灶数显著减少。Dmc1灶数量减少的程度与SC形成减少的程度相似。相反，物种杂交中相互遗传交换减少的程度远远大于焦点数量减少的程度。我们得出结论，Dmc1蛋白参与了同源性检查，但同源性检查失败对SC形成和互惠遗传交换的影响是不同的。
We examined the distribution of meiotic epitopes for the Dmc1 protein of lilies in a normal diploid, a triploid, and in a diploid species-hybrid. The triploid has an extra chromosome set; all three sets align, but only two of the three axes intimately pair at a given location. Our findings with the triploid support the idea that retention of the foci until the pachytene stage requires a successful homology check and synaptonemal complex (SC) initiation; the number of foci in the triploid diminishes by approximately 30% from early zygotene to pachytene, and the triploid pachytene values are similar to the pachytene values of the diploid. The species-hybrid lacks chromosome homology, has reduced SC formation and few reciprocal genetic exchanges. In this species-hybrid the number of foci at early zygotene is similar to that in the normal diploid but is dramatically reduced by mid-zygotene. The extent to which the number of Dmc1 foci is reduced is similar to the extent that SC formation is reduced. In contrast the extent of the reduction in reciprocal genetic exchange in the species-hybrid is much greater than the reduction in the number of foci. We conclude that Dmc1 protein is involved in homology checking, but the impact of failure to find homology affects SC formation and reciprocal genetic exchange differentially.