Genome-Wide Characterization of the Phenylalanine Ammonia-Lyase Gene Family and Their Potential Roles in Response to L. Infection in Cultivated Peanut ( L.)

Phenylalanine ammonia-lyase (PAL) is an essential enzyme in the phenylpropanoid pathway, in which numerous aromatic intermediate metabolites play significant roles in plant growth, adaptation, and disease resistance. Cultivated peanuts are highly susceptible to L. infection. Although genes have been characterized in various major crops, no systematic studies have been conducted in cultivated peanuts, especially in response to infection. In the present study, a systematic genome-wide analysis was conducted to identify genes in the L. genome. Ten genes were distributed unevenly on nine chromosomes. Based on phylogenetic analysis, the proteins were classified into three groups. Structural and conserved motif analysis of genes in revealed that all peanut genes contained one intron and ten motifs in the conserved domains. Furthermore, synteny analysis indicated that the ten genes could be categorized into five pairs and that each gene had a homologous gene in the wild-type peanut. Cis-element analysis revealed that the promoter region of the gene family was rich in stress- and hormone-related elements. Expression analysis indicated that genes from Group I ( and ), which had large number of ABRE, WUN, and ARE elements in the promoter, played a strong role in response to stress.