Láscarez-Lagunas Laura I, Martinez-Garcia Marina, Colaiácovo Monica P
Department of Genetics, Harvard Medical School, Boston, MA 02115, USA.
Department of Biotechnology-Plant Biology, School of Agricultural, Food and Biosystems Engineering, Universidad Politécnica de Madrid, 28040 Madrid, Spain.
Genes (Basel). 2022 Mar 19;13(3):546. doi: 10.3390/genes13030546.
To generate gametes, sexually reproducing organisms need to achieve a reduction in ploidy, via meiosis. Several mechanisms are set in place to ensure proper reductional chromosome segregation at the first meiotic division (MI), including chromosome remodeling during late prophase I. Chromosome remodeling after crossover formation involves changes in chromosome condensation and restructuring, resulting in a compact bivalent, with sister kinetochores oriented to opposite poles, whose structure is crucial for localized loss of cohesion and accurate chromosome segregation. Here, we review the general processes involved in late prophase I chromosome remodeling, their regulation, and the strategies devised by different organisms to produce bivalents with configurations that promote accurate segregation.
为了产生配子，有性生殖生物需要通过减数分裂实现倍性的降低。有几种机制来确保在第一次减数分裂（MI）时染色体正确减数分离，包括在减数第一次分裂前期后期的染色体重塑。交叉形成后的染色体重塑涉及染色体凝聚和重组的变化，产生一个紧密的二价体，姐妹动粒朝向相反的极，其结构对于局部黏连丧失和准确的染色体分离至关重要。在这里，我们综述了减数第一次分裂前期后期染色体重塑所涉及的一般过程、它们的调控以及不同生物为产生具有促进准确分离构型的二价体而设计的策略。
