Harper Lisa, Golubovskaya Inna, Cande W Zacheus
Department of Molecular and Cell Biology, University of California Berkeley, 345 LSA 3200, Berkeley, CA 94720-3200, USA.
J Cell Sci. 2004 Aug 15;117(Pt 18):4025-32. doi: 10.1242/jcs.01363.
During meiotic prophase, telomeres attach to the inner nuclear envelope and cluster to form the so-called meiotic bouquet. Although this has been observed in almost all organisms studied, its precise function remains elusive. The coincidence of telomere clustering and initiation of chromosome synapsis has led to the hypothesis that the bouquet facilitates homologous chromosome pairing and synapsis. However, recent mutant analysis suggests that the bouquet is not absolutely required for either homologous pairing or synapsis but that it makes both processes much faster and more efficient. The initiation of bouquet formation is independent of the initiation of recombination. However, the progression through recombination and synapsis may be required for exit from the bouquet stage. Little is known about the mechanism of telomere clustering but recent studies show that it is an active process.
在减数分裂前期,端粒附着于内核膜并聚集形成所谓的减数分裂花束。尽管在几乎所有研究过的生物体中都观察到了这一现象,但其确切功能仍不清楚。端粒聚集与染色体联会起始的巧合导致了这样一种假说,即花束促进同源染色体配对和联会。然而,最近的突变分析表明,花束对于同源配对或联会并非绝对必需,但它能使这两个过程更快且更高效。花束形成的起始独立于重组的起始。然而,从花束阶段退出可能需要通过重组和联会的进程。关于端粒聚集的机制知之甚少,但最近的研究表明这是一个活跃的过程。