Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC 27599, USA.
Genetics. 2013 Jun;194(2):327-34. doi: 10.1534/genetics.113.150581.
Meiotic crossovers facilitate the segregation of homologous chromosomes and increase genetic diversity. The formation of meiotic crossovers was previously posited to occur via two pathways, with the relative use of each pathway varying between organisms; however, this paradigm could not explain all crossovers, and many of the key proteins involved were unidentified. Recent studies that identify some of these proteins reinforce and expand the model of two meiotic crossover pathways. The results provide novel insights into the evolutionary origins of the pathways, suggesting that one is similar to a mitotic DNA repair pathway and the other evolved to incorporate special features unique to meiosis.
减数分裂交叉促进同源染色体的分离并增加遗传多样性。减数分裂交叉的形成以前被认为是通过两种途径发生的，每种途径的相对使用在生物体之间有所不同；然而，这种模式并不能解释所有的交叉，而且许多涉及的关键蛋白质尚未被识别。最近的研究确定了其中一些蛋白质，这加强和扩展了两种减数分裂交叉途径的模型。这些结果为这些途径的进化起源提供了新的见解，表明其中一种途径类似于有丝分裂 DNA 修复途径，另一种途径则进化为包含减数分裂特有的特殊特征。
