A Novel Retrotransposon Inserted in the Dominant Vrn-B1 Allele Confers Spring Growth Habit in Tetraploid Wheat (Triticum turgidum L.)

G3: Genes, Genomes, Genetics

L. Yan²  G.-T Yu¹  C. T. Tan²  S. Zhong⁴  C.-G. Chu⁴  S. S. Xu³ 

[1] Department of Entomology, North Dakota State University, Fargo, North Dakota 58108Department of Entomology, North Dakota State University, Fargo, North Dakota 58108Department of Entomology, North Dakota State University, Fargo, North Dakota 58108;Department of Plant and Soil Sciences, Oklahoma State University, Stillwater, Oklahoma 74078Department of Plant and Soil Sciences, Oklahoma State University, Stillwater, Oklahoma 74078Department of Plant and Soil Sciences, Oklahoma State University, Stillwater, Oklahoma 74078;United States Department of Agriculture, Agricultural Research Service, Northern Crop Science Laboratory, Fargo, North Dakota 58102United States Department of Agriculture, Agricultural Research Service, Northern Crop Science Laboratory, Fargo, North Dakota 58102United States Department of Agriculture, Agricultural Research Service, Northern Crop Science Laboratory, Fargo, North Dakota 58102;Department of Plant PathologyDepartment of Plant PathologyDepartment of Plant Pathology

关键词: Triticum turgidum;    tetraploid wheat;    vernalization;    Vrn-B1;    retrotransposon;   

DOI  :  10.1534/g3.111.001131

学科分类：生物科学（综合）

来源: Genetics Society of America

【 摘 要 】

Vernalization genes determine winter/spring growth habit in temperate cereals and play important roles in plant development and environmental adaptation. In wheat (Triticum L. sp.), it was previously shown that allelic variation in the vernalization gene VRN1 was due to deletions or insertions either in the promoter or in the first intron. Here, we report a novel Vrn-B1 allele that has a retrotransposon in its promoter conferring spring growth habit. The VRN-B1 gene was mapped in a doubled haploid population that segregated for winter-spring growth habit but was derived from two spring tetraploid wheat genotypes, the durum wheat (T. turgidum subsp. durum) variety ‘Lebsock’ and T. turgidum subsp. carthlicum accession PI 94749. Genetic analysis revealed that Lebsock carried the dominant Vrn-A1 and recessive vrn-B1 alleles, whereas PI 94749 had the recessive vrn-A1 and dominant Vrn-B1 alleles. The Vrn-A1 allele in Lebsock was the same as the Vrn-A1c allele previously reported in hexaploid wheat. No differences existed between the vrn-B1 and Vrn-B1 alleles, except that a 5463-bp insertion was detected in the 5′-UTR region of the Vrn-B1 allele. This insertion was a novel retrotransposon (designated as retrotrans_VRN), which was flanked by a 5-bp target site duplication and contained primer binding site and polypurine tract motifs, a 325-bp long terminal repeat, and an open reading frame encoding 1231 amino acids. The insertion of retrotrans_VRN resulted in expression of Vrn-B1 without vernalization. Retrotrans_VRN is prevalent among T. turgidum subsp. carthlicum accessions, less prevalent among T. turgidum subsp. dicoccum accessions, and rarely found in other tetraploid wheat subspecies.

【 授权许可】

Unknown