Genome-wide identification and expression analysis of the gene family in wheat ( L.).

Cytokinin is an important endogenous hormone in plants performing a wide spectrum of biological roles. The are primary cytokinin response genes, which are important components of the cytokinin signaling pathway and are involved in the regulation of plant growth and development. By analysis of the whole genome sequence of wheat, we identified 20 genes encoding RRAs which were clustered into eight homologous groups. The gene structure, conserved motifs, chromosomal location, and -acting regulatory elements of the were analyzed. Quantitative real-time polymerase chain reaction (qRT-PCR) results showed that the expression levels of most of the increased rapidly on exogenous cytokinin application. Moreover, the family members displayed different expression profiles under the stress treatments of drought, salt, cold, and heat. This study provides valuable insights into the gene family in wheat and promotes the potential application of these genes in wheat genetic improvement.