Structure, evolution, and comparative genomics of tetraploid cotton based on a high-density genetic linkage map.
Structure, evolution, and comparative genomics of tetraploid cotton based on a high-density genetic linkage map.
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DOI：
10.1093/dnares/dsw016
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发表时间：
2016-06
期刊：
影响因子：
--
通讯作者：
Lin Z
中科院分区：
文献类型：
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作者：
Li X;Jin X;Wang H;Zhang X;Lin Z
利用1885个新获得的基因座和3747个已发表的基因座构建高密度连锁图谱，其中包括5152个基因座，总长度4696.03 cM，平均距离0.91 cM。棉花基因组同源性分析进一步证实了预期的13对同源染色体，发现Chr10和Chr20上有明显的反转，Chr07和Chr16上有重复的反转。此外，Chr02和Chr03之间以及Chr04和Chr05之间还存在两个反向易位。四倍体棉花和二倍体棉花的比较基因组学表明，DT染色体和D染色体之间没有明显的结构变化，而AT染色体和A染色体之间存在较大的结构变化。四倍体棉花基因组与两种二倍体棉花混合基因组的Blast分析表明，无论来自AT基因组还是DT基因组，大多数AD染色体都优先与二倍体A基因组中相应的同源染色体匹配，然后与二倍体D基因组中相应的同源染色体匹配，说明二倍体D基因组在多倍体化过程中经过二倍体A基因组的转化进化形成DT基因组。此外，结果还反映了Chr01/Chr15、Chr02/Chr14、Chr03/Chr17、Chr04/Chr22和Chr05/Chr19之间发生了一系列染色体易位。
A high-density linkage map was constructed using 1,885 newly obtained loci and 3,747 previously published loci, which included 5,152 loci with 4696.03 cM in total length and 0.91 cM in mean distance. Homology analysis in the cotton genome further confirmed the 13 expected homologous chromosome pairs and revealed an obvious inversion on Chr10 or Chr20 and repeated inversions on Chr07 or Chr16. In addition, two reciprocal translocations between Chr02 and Chr03 and between Chr04 and Chr05 were confirmed. Comparative genomics between the tetraploid cotton and the diploid cottons showed that no major structural changes exist between DT and D chromosomes but rather between AT and A chromosomes. Blast analysis between the tetraploid cotton genome and the mixed genome of two diploid cottons showed that most AD chromosomes, regardless of whether it is from the AT or DT genome, preferentially matched with the corresponding homologous chromosome in the diploid A genome, and then the corresponding homologous chromosome in the diploid D genome, indicating that the diploid D genome underwent converted evolution by the diploid A genome to form the DT genome during polyploidization. In addition, the results reflected that a series of chromosomal translocations occurred among Chr01/Chr15, Chr02/Chr14, Chr03/Chr17, Chr04/Chr22, and Chr05/Chr19.