Genome-Wide Identification, Characterization, and Expression Profiling of Superfamily Genes under Different Development and Abiotic Stress Conditions in Pecan ().

The ethylene-responsive element () is one of the keys and conserved transcription factors (TFs) in plants that play a vital role in regulating plant growth, development, and stress response. A total of 202 genes were identified from the pecan genome and renamed according to the chromosomal distribution of the genes. They were divided into four subfamilies according to the domain and phylogenetic analysis, including 26 , 168 , six , and two gene family members. These genes were distributed randomly across the 16 chromosomes, and we found 19 tandem and 146 segmental duplications which arose from ancient duplication events. The gene structure and conserved motif analysis demonstrated the conserved nature of intron/exon organization and motifs among the genes. Several cis-regulatory elements, which were related to light responsiveness, stress, and defense responses, were identified in the promoter regions of s. The expression profiling of 202 genes was assessed by using RNA-Seq data and qRT-PCR during development (pistillate flowering development, graft union development, and kernel development) and under abiotic stresses (waterlogging, drought). Moreover, the results suggested that the ERF-VII members may play a critical role in waterlogging stress. These findings provided new insights into gene evolution and divergence in pecan and can be considered a valuable resource for further functional validation, as well as for utilization in a stress-resistance-variety development program.