Genome-Wide Characterization of the Gene Family in Poplar and Expression Analysis in Response to Hormones and Biotic/Abiotic Stresses.

The (Broad-complex, tramtrack, and bric-a-brac) gene family, characterized by a highly conserved BTB domain, is implicated in a spectrum of biological processes, encompassing growth and development, as well as stress responses. Characterization and functional studies of genes in poplar are still limited, especially regarding their response to hormones and biotic/abiotic stresses. In this study, we conducted an HMMER search in conjunction with BLASTp and identified 95 gene models in . Through domain motif and phylogenetic relationship analyses, these proteins were classified into eight families, NPH3, TAZ, Ankyrin, only BTB, BACK, Armadillo, TPR, and MATH. Collinearity analysis of poplar genes with homologs in six other species elucidated evolutionary relationships and functional conservations. RNA-seq analysis of five tissues of poplar identified genes as playing a pivotal role during developmental processes. Comprehensive RT-qPCR analysis of 11 genes across leaves, roots, and xylem tissues revealed their responsive expression patterns under diverse hormonal and biotic/abiotic stress conditions, with varying degrees of regulation observed in the results. This study marks the first in-depth exploration of the gene family in poplar, providing insights into the potential roles of genes in hormonal regulation and response to stress.