Bozza C G, Pawlowski W P
Department of Plant Breeding and Genetics, Cornell University, Ithaca, NY 14853, USA.
Cytogenet Genome Res. 2008;120(3-4):313-9. doi: 10.1159/000121080. Epub 2008 May 23.
Three activities hallmark meiotic cell division: homologous chromosome pairing, synapsis, and recombination. Recombination and synapsis are well-studied but homologous pairing still holds many black boxes. In the past several years, many studies in plants have yielded insights into the mechanisms of chromosome pairing interactions. Research in several plant species showed the importance of telomere clustering on the nuclear envelope (telomere bouquet formation) in facilitating alignment of homologous chromosomes. Homologous pairing was also shown to be tied to the early stages of recombination by mutant analyses in Arabidopsis and maize. In contrast, little is known about the mechanisms that guide homolog interaction after their rough alignment by the bouquet and before the close-range recombination-dependent homology search. The relatively large and complex genomes of plants may require additional mechanisms, not needed in small genome eukaryotes, to distinguish between local homology of duplicated genes or transposable elements and global chromosomal homology. Plants provide an excellent large genome model for the study of homologous pairing and dissection of this process.
同源染色体配对、联会和重组。重组和联会已得到充分研究，但同源配对仍存在许多未知之处。在过去几年中，许多针对植物的研究深入了解了染色体配对相互作用的机制。对几种植物物种的研究表明，核膜上的端粒聚集（端粒花束形成）在促进同源染色体排列方面具有重要作用。通过拟南芥和玉米的突变分析还表明，同源配对与重组的早期阶段相关。相比之下，对于在花束引导同源染色体初步排列之后、近距离依赖重组的同源性搜索之前指导同源物相互作用的机制，我们知之甚少。植物相对较大且复杂的基因组可能需要额外的机制（小基因组真核生物不需要）来区分重复基因或转座元件的局部同源性与全局染色体同源性。植物为研究同源配对及剖析这一过程提供了一个出色的大基因组模型。
