Genome Identification and Expression Profiling of the Gene Family in under Abiotic Stresses.

PIN-formed (PIN) proteins-specific transcription factors that are widely distributed in plants-play a pivotal role in regulating polar auxin transport, thus influencing plant growth, development, and abiotic stress responses. Although the identification and functional validation of genes have been extensively explored in various plant species, their understanding in woody plants-particularly the endangered species (Hemsl.) Yang-remains limited. is an economically significant tree species that is endemic to southern China. For this study, we employed bioinformatics approaches to screen and identify 13 members of the gene family in . Through a phylogenetic analysis, we classified these genes into five sub-families: A, B, C, D, and E. Furthermore, we conducted a comprehensive analysis of the physicochemical properties, three-dimensional structures, conserved motifs, and gene structures of the PbPIN proteins. Our results demonstrate that all genes consist of exons and introns, albeit with variations in their number and length, highlighting the conservation and evolutionary changes in genes. The results of our collinearity analysis indicate that the expansion of the gene family primarily occurred through segmental duplication. Additionally, by predicting cis-acting elements in their promoters, we inferred the potential involvement of genes in plant hormone and abiotic stress responses. To investigate their expression patterns, we conducted a comprehensive expression profiling of genes in different tissues. Notably, we observed differential expression levels of s across the various tissues. Moreover, we examined the expression profiles of five representative genes under abiotic stress conditions, including heat, cold, salt, and drought stress. These experiments preliminarily verified their responsiveness and functional roles in mediating responses to abiotic stress. In summary, this study systematically analyzes the expression patterns of genes and their response to abiotic stresses in using whole-genome data. Our findings provide novel insights and valuable information for stress tolerance regulation in . Moreover, the study offers significant contributions towards unraveling the functional characteristics of the gene family.