title: Molecular evolution of the Sorghum Maturity Gene Ma3.
abstract: Time to maturity is a critical trait in sorghum (Sorghum bicolor) breeding, as it determines whether a variety can be grown in a particular cropping system or ecosystem. Understanding the nucleotide variation and the mechanisms of molecular evolution of the maturity genes would be helpful for breeding programs. In this study, we analyzed the nucleotide diversity of Ma3, an important maturity gene in sorghum, using 252 cultivated and wild sorghum materials from all over the world. The nucleotide variation and diversity were analyzed based both on race- and usage-based groups. We also sequenced 12 genes around the Ma3 gene in 185 of these materials to search for a selective sweep and found that purifying selection was the strongest force on Ma3, as low nucleotide diversity and low-frequency amino acid variants were observed. However, a very special mutation, described as ma3R, seemed to be under positive selection, as indicated by dramatically reduced nucleotide variation not only at the loci but also in the surrounding regions among individuals carrying the mutations. In addition, in an association study using the Ma3 nucleotide variations, we detected 3 significant SNPs for the heading date at a high-latitude environment (Beijing) and 17 at a low-latitude environment (Hainan). The results of this study increases our understanding of the evolutionary mechanisms of the maturity genes in sorghum and will be useful in sorghum breeding.
authors.affiliation: Department of Plant Genetics and Breeding, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China; Beijing Key Laboratory of Crop Genetic Improvement and Genome, Ministry of Agriculture, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Plant Genetics and Breeding, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China; Beijing Key Laboratory of Crop Genetic Improvement and Genome, Ministry of Agriculture, Beijing, China.
authors.forename: Lubin
authors.initials: L
authors.lastname: Tan
authors.affiliation: Department of Plant Genetics and Breeding, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China; Beijing Key Laboratory of Crop Genetic Improvement and Genome, Ministry of Agriculture, Beijing, China.
authors.forename: Yongcai
authors.initials: Y
authors.lastname: Fu
authors.affiliation: Department of Plant Genetics and Breeding, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China; Beijing Key Laboratory of Crop Genetic Improvement and Genome, Ministry of Agriculture, Beijing, China.
authors.forename: Zuofeng
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: Department of Plant Genetics and Breeding, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China; Beijing Key Laboratory of Crop Genetic Improvement and Genome, Ministry of Agriculture, Beijing, China.
authors.forename: Fengxia
authors.initials: F
authors.lastname: Liu
authors.affiliation: Department of Plant Genetics and Breeding, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China; Beijing Key Laboratory of Crop Genetic Improvement and Genome, Ministry of Agriculture, Beijing, China.
authors.forename: Chuanqing
authors.initials: C
authors.lastname: Sun
authors.affiliation: Department of Plant Genetics and Breeding, College of Agronomy and Biotechnology, China Agricultural University, Beijing, China; Beijing Key Laboratory of Crop Genetic Improvement and Genome, Ministry of Agriculture, Beijing, China.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Cai
mesh_terms: D019143:Evolution, Molecular; D017343:Genes, Plant; D056726:Genetic Association Studies; D014644:Genetic Variation; D018745:Genome, Plant; D020641:Polymorphism, Single Nucleotide; D045868:Sorghum / Q000235:genetics*