Genome-wide identification of CUC gene family and functional analysis of HcCUC1 in kenaf

CUP-SHAPED COTYLEDON (CUC) transcription factors have a central regulatory function in plant growth and development. However, their involvement kenaf (Hibiscus cannabinus L.) remains largely unexplored. In this study, we conducted comprehensive analysis to identify six HcCUC genes the genome. Through bioinformatic analysis, found that share similar motifs highly conserved gene structures. Phylogenetic categorized into two groups, shared similarities with CUC2 or CUC3 from other species. Collinearity revealed formation of 6 syntenic pairs among genes, 8 homologous three AtCUC Arabidopsis. To investigate tissue-specific expression, analyzed transcriptome data, showed differential expression particularly leaves during seedling stage, buds maturation anthers at dual-core period. Functional characterization HcCUC1 was achieved through its overexpression Arabidopsis, resulting elongated cotyledons, absent petioles increased number rosette leaf lateral branches. qRT-PCR potentially influences branch development by up-regulating auxin-related (AtYUC2, AtYUC4, AtPIN1, AtPIN3, AtPIN4) shape-related (AtKNAT2, AtKNAT6). Notably, down-regulated flowering-related (AtFT, AtAP1, AtLFY, AtFUL), causing delayed flowering. Overall, our findings emphasize pivotal role regulating growth, development, flowering time, provide valuable insights genetic regulation genes. Six were identified genome, playing as well time.