Rey María-Dolores, Ramírez Carmen, Martín Azahara C
Agroforestry and Plant Biochemistry, Proteomics and Systems Biology, Department of Biochemistry and Molecular Biology, University of Córdoba, 14014 Córdoba, Spain.
Institute for Sustainable Agriculture (IAS-CSIC), Department of Plant Genetic Improvement, 14004 Córdoba, Spain.
Plants (Basel). 2021 Jan 7;10(1):113. doi: 10.3390/plants10010113.
Polyploidization, or whole genome duplication (WGD), has an important role in evolution and speciation. One of the biggest challenges faced by a new polyploid is meiosis, in particular, discriminating between multiple related chromosomes so that only homologs recombine to ensure regular chromosome segregation and fertility. Here, we report the production of two new hybrids formed by the genomes of species from three different genera: a hybrid between (DD), (HH), and (RR) with the haploid genomic constitution HDR (n = 7× = 21); and a hybrid between (AABB), and with the constitution ABHR (n = 7× = 28). We used genomic hybridization and immunolocalization of key meiotic proteins to establish the chromosome composition of the new hybrids and to study their meiotic behavior. Interestingly, there were multiple chromosome associations at metaphase I in both hybrids. A high level of crossover (CO) formation was observed in HDR, which shows the possibility of meiotic recombination between the different genomes. We succeeded in the duplication of the ABHR genome, and several amphiploids, AABBHHRR, were obtained and characterized. These results indicate that recombination between the genera of three economically important crops is possible.
多倍体化，即全基因组加倍（WGD），在进化和物种形成中起着重要作用。新形成的多倍体面临的最大挑战之一是减数分裂，特别是区分多个相关染色体，以便只有同源染色体进行重组，以确保正常的染色体分离和育性。在此，我们报告了由来自三个不同属的物种基因组形成的两个新杂种的产生：一个是（DD）、（HH）和（RR）之间的杂种，其单倍体基因组组成为HDR（n = 7× = 21）；另一个是（AABB）、和之间的杂种，组成为ABHR（n = 7× = 28）。我们使用基因组杂交和关键减数分裂蛋白的免疫定位来确定新杂种的染色体组成，并研究它们的减数分裂行为。有趣的是，两个杂种在减数第一次分裂中期都有多个染色体联会。在HDR中观察到高水平的交叉（CO）形成，这表明不同基因组之间减数分裂重组的可能性。我们成功地复制了ABHR基因组，并获得并鉴定了几个双二倍体AABBHHRR。这些结果表明，三种重要经济作物的属间重组是可能的。
