Comprehensive Updated Genome-Wide Identification and Expression Patterns of the TaGeBP Gene Family in Wheat

The GLABROUS1 Enhancer Binding Protein (GeBP) family, plant-specific transcription factors with a non-classical Leu-zipper motif, plays crucial roles in plant development and stress responses. Although GeBP genes have been characterized in several Gramineae crops, including a preliminary genome-wide identification of 11 GeBP genes in common wheat (Triticum aestivum L.), a comprehensive and systematic analysis of the TaGeBP family remains lacking. In this study, 37 TaGeBP genes were identified in the wheat genome (cv. Chinese Spring), representing a substantially higher number than the 11 reported in the prior study. This discrepancy is likely attributable to the integration of updated genome assemblies, refined gene identification criteria, and comprehensive domain validation. Phylogenetic analysis classified these 37 TaGeBPs into four distinct groups, with members within the same subgroup sharing conserved exon-intron architectures and protein motif compositions. Promoter cis-acting element analysis revealed significant enrichment of motifs associated with abiotic stress responses and phytohormone signaling, implying potential involvement of TaGeBPs in mediating plant adaptive processes. Evolutionary analysis indicated that TaGeBP family expansion was primarily driven by allopolyploidization and segmental duplication, with purifying selection constraining their sequence divergence. Members within the same subgroup shared similar exon-intron structures and conserved protein motifs. Promoter analysis revealed that TaGeBP genes are enriched with cis-elements related to stress and phytohormone responses, suggesting their potential involvement in adaptive processes. Gene expansion in the TaGeBP family was mainly driven by allopolyploidization and segmental duplication, with evolution dominated by purifying selection. Tissue-specific expression profiling demonstrated that most TaGeBPs are preferentially expressed in roots and spikes, with varying expression patterns across different tissues. Under salt and drought stresses, qRT-PCR results indicated diverse response profiles among TaGeBPs. Furthermore, subcellular localization confirmed the nuclear presence of selected TaGeBPs, supporting their predicted role as transcription factors. These findings offer important insights for further functional characterization of TaGeBP genes, particularly regarding their roles in abiotic stress tolerance.