VRN-1 gene- associated prerequisites of spring growth habit in wild tetraploid wheat T. dicoccoides and the diploid A genome species

BMC Plant Biology

Research Article

Elena A Salina¹  Kseniya V Strygina¹  Andrey B Shcherban¹ 

[1] Institute of Cytology and Genetics, Lavrentiev ave. 10, 630090, Novosibirsk, Russia;

关键词: Allelic diversity;    Vernalization;    VRN-1;    Promoter;    First intron;    Tetraploid;    Diploid;    Triticum;   

DOI  :  10.1186/s12870-015-0473-x

 received in 2014-12-05, accepted in 2015-03-16,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundIn order to clarify the origin of spring growth habit in modern domesticated wheat, allelic variability of the VRN-1 gene was investigated in a wide set of accessions of the wild tetraploid species Triticum dicoccoides (BBAA), together with diploid species T. monococcum, T. boeoticum and T. urartu, presumable donors of the A genome to polyploid wheats.ResultsNo significant variation was found at the VRN-B1 locus of T. dicoccoides, whereas at VRN-A1 a number of previously described alleles were found with small deletions in the promoter (VRN-A1b, VRN-A1d) or a large deletion in the first (1st) intron (VRN-A1L). The diploid A genome species were characterized by their own set of VRN-1 alleles including previously described VRN-A1f and VRN-A1h alleles with deletions in the promoter region and the VRN-A1ins allele containing a 0.5 kb insertion in the 1st intron. Based on the CAPS screening data, alleles VRN-A1f and VRN-A1ins were species-specific for T. monococcum, while allele VRN-A1h was specific for T. boeoticum. Different indels were revealed in both the promoter and 1st intron of the recessive VRN-A1u allele providing specific identification of T. urartu, the proposed donor of the A genome to modern wheat. We found that alleles VRN-A1b and VRN-A1h, previously described as dominant, have either no or weak association with spring growth habit, while in some diploid accessions this habit was associated with the recessive VRN-A1 allele.ConclusionsSpring growth habit in diploid wheats was only partially associated with indels in regulatory regions of the VRN-1 gene. An exception is T. monococcum where dominant mutations in both the promoter region and, especially, the 1st intron were selected during domestication resulting in a greater variety of spring forms. The wild tetraploid T. dicoccoides had a distinct set of VRN-A1 alleles compared to the diploids in this study, indicating an independent origin of spring tetraploid forms that likely occurred after combining of diploid genomes. These alleles were subsequently inherited by cultivated polyploid (tetraploid and hexaploid) descendants.

【 授权许可】

CC BY   
© Shcherban et al.; licensee BioMed Central. 2015