School of Agriculture and Food Sciences, The University of Queensland, Brisbane, 4072, Qld, Australia.
Centre for Integrative Legume Research, The University of Queensland, Brisbane, 4072, Qld, Australia.
New Phytol. 2014 May;202(3):964-974. doi: 10.1111/nph.12706. Epub 2014 Jan 28.
How do chromosomal regions with differing degrees of homology and homeology interact at meiosis? We provide a novel analytical method based on simple genetics principles which can help to answer this important question. This method interrogates high-throughput molecular marker data in order to infer chromosome behavior at meiosis in interspecific hybrids. We validated this method using high-resolution molecular marker karyotyping in two experimental Brassica populations derived from interspecific crosses among B. juncea, B. napus and B. carinata, using a single nucleotide polymorphism chip. This method of analysis successfully identified meiotic interactions between chromosomes sharing different degrees of similarity: full-length homologs; full-length homeologs; large sections of primary homeologs; and small sections of secondary homeologs. This analytical method can be applied to any allopolyploid species or fertile interspecific hybrid in order to detect meiotic associations. This genetic information can then be used to identify which genomic regions share functional homeology (i.e., retain enough similarity to allow pairing and segregation at meiosis). When applied to interspecific hybrids for which reference genome sequences are available, the question of how differing degrees of homology and homeology affect meiotic interactions may finally be resolved.
不同同源性和同线性程度的染色体区域如何在减数分裂中相互作用？我们提供了一种基于简单遗传原理的新分析方法，可以帮助回答这个重要问题。该方法通过分析高通量分子标记数据来推断种间杂种减数分裂过程中的染色体行为。我们使用来自 B. juncea、B. napus 和 B. carinata 种间杂交的两个实验 Brassica 群体，使用单核苷酸多态性芯片，通过高分辨率分子标记核型分析验证了该方法。该分析方法成功地鉴定了具有不同相似程度的染色体之间的减数分裂相互作用：全长同源物；全长同系物；主要同系物的大部分；以及次要同系物的小部分。这种分析方法可以应用于任何异源多倍体物种或可育的种间杂种，以检测减数分裂的相关性。然后，可以利用这些遗传信息来确定哪些基因组区域具有功能同线性（即保留足够的相似性，允许在减数分裂中配对和分离）。当应用于具有参考基因组序列的种间杂种时，关于不同同源性和同线性程度如何影响减数分裂相互作用的问题最终可能会得到解决。
