Genome-wide identification and expression analysis of the EgTCP transcription factor family in Eucalyptus grandis.

The TCP (Teosinte Branched 1/Cycloidea/Proliferating Cell Factors) transcription factor family plays a critical role in plant growth, development, and stress responses. To investigate the functions of the TCP gene family in Eucalyptus grandis (E. grandis), we performed a comprehensive genome-wide identification and analysis of E. grandis TCP (EgTCP) genes using bioinformatics approaches. We examined their expression patterns across different tissues and under salicylic acid (SA), jasmonic acid (JA), and salt stress conditions. Our analysis identified 15 TCP genes in the E. grandis genome, designated EgTCP1-EgTCP15. The encoded proteins range from 194 to 427 amino acid residues, with molecular weights between 21.68 and 44.90 kDa and isoelectric points spanning 6.45-0.41. Biochemical property predictions classified all EgTCP proteins as hydrophilic and unstable. Chromosomal mapping revealed that EgTCP genes are unevenly distributed across 11 chromosomes. Gene structure analysis indicated that EgTCP genes contain one to two exons and up to one intron. The presence of a highly conserved TCP domain was confirmed by conserved motif and phylogenetic analyses, which classified EgTCP proteins into three subfamilies: PCF, CIN, and CYC/TB1. Cis-regulatory element analysis of the promoter regions revealed multiple hormone-responsive and stress-related elements, suggesting potential regulatory roles in plant growth and abiotic stress adaptation. Expression profiling indicated that most EgTCP genes respond to SA and JA induction and exhibit tissue-specific expression patterns. The subcellular localization experiment indicated that EgTCP 13 was located in the nucleus. Overall, these findings provide valuable insights into the functional roles of the TCP gene family in E. grandis, establishing a foundation for future studies on their biological significance in plant growth, development, and stress tolerance. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-025-01623-0.