Lukjanová Eliška, Hanulíková Alžběta, Řepková Jana
Department of Experimental Biology, Faculty of Sciences, Masaryk University, 611 37 Brno, Czech Republic.
Plants (Basel). 2023 Jan 4;12(2):235. doi: 10.3390/plants12020235.
L. is a wild polyploid relative of the agriculturally important red clover that possesses traits promising for breeding purposes. To date, also remains the only clover species with which agriculturally important red clover has successfully been hybridized. Even though allopolyploid origin has previously been suggested, little has in fact been known about the karyotype and its origin. We researched and related karyotypes using comparative cytogenomic methods, such as fluorescent in situ hybridization (FISH) and RepeatExplorer cluster analysis. The results indicate an exceptional karyotype diversity regarding numbers and mutual positions of 5S and 26S rDNA loci and centromeric repeats in populations of ecotypes and varieties. The observed variability among ecotypes and varieties suggests current karyotype instability that can be attributed to ever-ongoing battle between satellite DNA together with genomic changes and rearrangements enhanced by post-hybridization events. Comparative cytogenomic analyses of a hexaploid variety and diploid relatives revealed stable karyotypes with a possible case of chromosomal rearrangement. Moreover, the results provided evidence of having autopolyploid origin.
L. 是农业上重要的红三叶草的野生多倍体近缘种，具有对育种有前景的性状。迄今为止，它也是唯一与农业上重要的红三叶草成功杂交的三叶草物种。尽管之前有人提出它具有异源多倍体起源，但实际上对其核型及其起源了解甚少。我们使用比较细胞基因组学方法，如荧光原位杂交（FISH）和RepeatExplorer聚类分析，研究了L. 及其相关核型。结果表明，在L. 生态型和品种群体中，5S和26S rDNA位点以及着丝粒重复序列的数量和相互位置存在异常的核型多样性。在L. 生态型和品种中观察到的变异性表明当前核型不稳定，这可归因于卫星DNA之间持续不断的斗争以及杂交后事件增强的基因组变化和重排。对一个L. 六倍体品种及其二倍体近缘种的比较细胞基因组分析揭示了稳定的核型以及一个可能的染色体重排案例。此外，结果提供了L. 具有同源多倍体起源的证据。
