title: Structure, evolution, and comparative genomics of tetraploid cotton based on a high-density genetic linkage map.
abstract: 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.
authors.affiliation: National Key Laboratory of Crop Genetic Improvement (Wuhan), Huazhong Agricultural University, Wuhan, Hubei 430070, China College of Agronomy and Plant Protection, Qingdao Agricultural University/Shandong Key Laboratory of Dryland Farming Technology, Qingdao, Shandong, China.
authors.forename: Ximei
authors.initials: X
authors.lastname: Li
authors.affiliation: National Key Laboratory of Crop Genetic Improvement (Wuhan), Huazhong Agricultural University, Wuhan, Hubei 430070, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Jin
authors.affiliation: National Key Laboratory of Crop Genetic Improvement (Wuhan), Huazhong Agricultural University, Wuhan, Hubei 430070, China.
authors.forename: Hantao
authors.initials: H
authors.lastname: Wang
authors.affiliation: National Key Laboratory of Crop Genetic Improvement (Wuhan), Huazhong Agricultural University, Wuhan, Hubei 430070, China.
authors.forename: Xianlong
authors.initials: X
authors.lastname: Zhang
authors.affiliation: National Key Laboratory of Crop Genetic Improvement (Wuhan), Huazhong Agricultural University, Wuhan, Hubei 430070, China linzhongxu@mail.hzau.edu.cn.
authors.forename: Zhongxu
authors.initials: Z
authors.lastname: Lin
mesh_terms: D002874:Chromosome Mapping; D019143:Evolution, Molecular; D008040:Genetic Linkage; D018745:Genome, Plant; D056914:Genomic Structural Variation; D003368:Gossypium / Q000235:genetics*; D057891:Tetraploidy
keywords: comparative genomics; evolution; genetic linkage map; genome structure; tetraploid cotton