Genome-Wide Identification and Expression of Gene Family Provide Insight Into Pod Development in Peanut ().

The () transcription family were initially identified as important factors for phytochrome A (phyA)-mediated far-red light signaling in ; they play crucial roles in controlling the growth and development of plants. The reported reference genome sequences of , including , , , and , and its related species provide an opportunity to systematically perform a genome-wide identification of homologous genes and investigate expression patterns of these members in peanut species. Here, a total of 650 genes were identified from four and its closely related species . Of the studied species, contained the most (246) genes, which can be classified into three subgroups based on phylogenic relationships. The synonymous () and non-synonymous () substitution rates, phylogenetic relationship and synteny analysis of the family provided deep insight into polyploidization, evolution and domestication of peanut genes. The transcriptome data showed that the genes exhibited distinct tissue- and stage-specific expression patterns in peanut. Three candidate genes including , , and , specifically expressed in peg and pod, might participate in pod development in the peanut. The quantitative real-time PCR (qRT-PCR) analyses confirmed that the three selected genes were highly and specifically expressed in the peg and pod. This study systematically analyzed gene structure, evolutionary characteristics and expression patterns of gene family, which will provide a foundation for the study of genetic and biological function in the future.