TaASY1 promotes homologous chromosome interactions and is affected by deletion of Ph1
TaASY1 promotes homologous chromosome interactions and is affected by deletion of Ph1
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DOI：
10.1111/j.1365-313x.2008.03701.x
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发表时间：
2009-02-01
期刊：
影响因子：
7.2
通讯作者：
Able, Jason A.
中科院分区：
文献类型：
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作者：
Boden, Scott A.;Langridge, Peter;Able, Jason A.
在减数分裂过程中，染色体被分类成同源对，作为它们通过重组和突触紧密结合的序言。然而，人们对用于区分同源染色体与细胞核中其他染色体的机制知之甚少。对小麦 (Triticum aestivum) 的研究表明，需要配对同源 1 (Ph1) 基因座来抑制遗传相似的同源染色体之间的相互作用。在这里，我们发现 Ph1 的缺失会导致 Asynapsis 1 (ASY1) 的转录增加，该基因编码轴元件相关蛋白，对于拟南芥和水稻的突触和交叉形成至关重要。减数分裂期间 ASY1 的定位也受到 Ph1 缺失的影响。此外，TaASY1活性降低的转基因小麦突变体在前期I表现出突触减少，并在中期I表现出同源染色体之间的配对。这些结果表明，ASY1是促进面包小麦同源染色体之间相互作用所必需的，并且Ph1具有基因调节作用，这与其作为Cdk样基因的遗传特性一致。这项研究的更广泛的意义表明，我们可以使用 Taasy1 突变体来评估它们在外来染色质渗入研究中的功效，就像 ph1b 突变体一样。
During meiosis, chromosomes are sorted into homologous pairs as a preface to their intimate association via recombination and synapsis. However, little is known about the mechanism used to distinguish homologous chromosomes from other chromosomes present in the nucleus. Studies in wheat (Triticum aestivum) have shown that the Pairing homoeologous 1 (Ph1) locus is required to suppress interactions between genetically similar homoeologous chromosomes. Here we show that absence of Ph1 causes increased transcription of Asynapsis 1 (ASY1), a gene that encodes an axial-element-associated protein that is essential for synapsis and cross-over formation in Arabidopsis and rice. Localisation of ASY1 during meiosis is also affected by deletion of Ph1. In addition, transgenic wheat mutants with decreased activity of TaASY1 display reduced synapsis during prophase I and exhibit pairing between homoeologous chromosomes at metaphase I. These results suggest that ASY1 is required to promote interactions between homologous chromosomes in bread wheat, and that Ph1 has a gene regulatory role, which is consistent with its suggested genetic identity as a Cdk-like gene. Broader implications of this research suggest that we could use the Taasy1 mutants to assess their efficacy in alien chromatin introgression studies, as seen with the ph1b mutant.