Genome-wide identification and evolution of HECT genes in wheat.

BACKGROUND

As an important class of E3 ubiquitin ligases in the ubiquitin proteasome pathway, proteins containing homologous E6-AP carboxyl terminus (HECT) domains are crucial for growth, development, metabolism, and abiotic and biotic stress responses in plants. However, little is known about genes in wheat ( L.), one of the most important global crops.

METHODS

Using a genome-wide analysis of high-quality wheat genome sequences, we identified 25 genes classified into six groups based on the phylogenetic relationship among wheat, rice, and .

RESULTS

The predicted genes were distributed evenly in 17 of 21 chromosomes of the three wheat subgenomes. Twenty-one of these genes were hypothesized to be segmental duplication genes, indicating that segmental duplication was significantly associated with the expansion of the wheat gene family. The Ka/Ks ratios of the segmental duplication of these genes were less than 1, suggesting purifying selection within the gene family. The expression profile analysis revealed that the 25 wheat genes were differentially expressed in 15 tissues, and genes in Group II, IV, and VI (, , ) were highly expressed in roots, stems, and spikes. This study contributes to further the functional analysis of the gene family in wheat.