Moens Peter B
Department of Biology, York University, 4700 Keele Street, Toronto, Ontario M3J 1P3, Canada.
Genome. 2006 Mar;49(3):205-8. doi: 10.1139/g06-021.
With immunofluorescence microscopy, the positions of centromeres and MLH1 (MutL homolog) foci representing the sites of presumptive chiasmata are shown for zebrafish (Danio rerio Hamilton 1822) synaptonemal complexes (SCs) in spermatocyte nuclei at meiotic prophase. Most SCs have a single focus and a few (7 of 140) have 2 chiasmata. MLH1 foci tend to be in the distal regions of SCs, with progressively fewer occurring towards the middle of the SCs. This non-random distribution suggests chiasma interference. Synaptic initiation, as well as replication protein A (RPA) foci at the chromosome ends, correlates with the distal localization of MLH1 foci. These observations may provide the physical basis for the reported limited genetic recombination in the centromeric region of androgenetic offspring of a male.
通过免疫荧光显微镜观察，展示了减数分裂前期精母细胞核中斑马鱼（Danio rerio Hamilton 1822）联会复合体（SCs）的着丝粒位置以及代表假定交叉位点的MLH1（MutL同源物）焦点。大多数SCs有一个单一焦点，少数（140个中有7个）有2个交叉。MLH1焦点倾向于位于SCs的远端区域，朝着SCs中间逐渐减少。这种非随机分布表明存在交叉干涉。突触起始以及染色体末端的复制蛋白A（RPA）焦点与MLH1焦点的远端定位相关。这些观察结果可能为报道的雄性孤雄生殖后代着丝粒区域有限的基因重组提供物理基础。
