Molecular Cloning, Characterization, and Expression Analysis of Genes Encoding Gibberellin 20-Oxidase in Dasypyrum villosum Dwarf Mutant

Thirty-six gene sequences encoding the gibberellin (GA) 20-oxidase were obtained from Dasypyrum villosum and its dwarf mutant. Sequence alignment showed that there were 21 SNPs and 4 InDels among these sequences which could be divided into three haplotypes-haplotype I, II, and III with 1,293, 1,297, and 1,294 bp in length, respectively. They contained a CDS with 1,080 bp in length encoding a putative polypeptide of 359 amino acids. Two haplotypes were found in wild type (I and II) and dwarf mutant (II and III), respectively. Q-PCR analysis showed that in the whole growing stages, the majority expression levels of haplotypes from wild types were higher than that of dwarf mutant, suggesting that wild types could synthesize more active GA substrates than dwarf mutant. The expression level in stem nodes and internodes between wild type and dwarf mutant were not significantly different, whereas their expression levels in roots were distinctly distinguished from each other in seedling, stem elongation, and heading stages, implying that most active GAs were synthesized in the root, and some were consumed by the root itself, and the others might be transported to other organs.