Molecular Cloning, Characterization, and Expression Analysis of DROOPING LEAF gene in the Pistillody Line of Common Wheat

In this article, we report the cloning, characterization, and expression pattern of Triticum aestivum DROOPING LEAF gene (TaDL) in pistillody line of common wheat. Three TaDL homoeologous genes (TaDL1, TaDL2, and TaDL3) were isolated and found to be located on chromosomes 4AS, 4DL, and 4BL, respectively. The putative TaDL1, TaDL2, and TaDL3 protein were 22.4, 22.6, and 22.3 kDa, with theoretical pI of 9.04, 9.04, and 8.98 and containing two distinct domains, namely, a zinc-finger domain in the N-terminal region and a C-terminal YABBY domain. The genome sequence of the three homologous genes consisted seven exons and six introns. All the introns, except for intron VI, varied in length and sequence composition. Phylogenetic analysis revealed that TaDL was most closely related to the Brachypodium distachyon BdDL and Oryza sativa DL genes. The expression pattern analysis indicated that TaDL1, TaDL2, and TaDL3 have a higher expression levels in PS and P; however, the three genes are very rare in S. Thus, TaDL gene may contribute to pistil development. Moreover, overexpression of TaDL gene in stamens may cause complete or partial homeosis of stamens into pistils in wheat.