Molecular characterization and marker development for high molecular weight glutenin subunit 1Dy12** from Yunnan hulled wheat

Abstract

High molecular weight glutenin subunits (HMW-GSs) play an important role in affecting dough viscoelasticity and extensibility. In this work, the novel HMW-GS gene 1Dy12** in Yunnan hulled wheat was cloned and characterized, and the molecular marker for identifying this gene was developed. SDS-PAGE analysis indicated that the mobility of 1Dy12** was the same as that of 1Dy12. The coding sequence of 1Dy12** was 1953 bp, which was 33 bp less than that of 1Dy12. 1Dy12** possessed 649 amino acid residues and showed a similar molecular structure to the published y-type subunit. It possessed four domains: a signal peptide, a conservative N-terminal domain, a large repetitive domain, and a conservative C-terminal domain. Eight cysteine residues were present in 1Dy12**, which was one more than the conserved number of cysteine residues in the y-type subunit. In vitro SDS-sedimentation tests demonstrated that 1Dy12** could bring higher SDS-sedimentation volumes than those of 1Dy10 or 1Dy12. A set of functional markers for the 1Dy12** gene was developed and validated on 36 bread wheat varieties with different Glu-1 alleles and 48 recombinant inbred lines derived by Yunnan hulled wheat and Yanzhan 1. The markers could effectively distinguish 1Dy12** from other HMW-GS genes and, thus, provide a useful tool for marker-assisted selection in wheat quality improvement programs.