Genome-Wide Identification and Analysis of the Growth-Regulating Factor Family in DC and Functional Analysis of in Leaf Size and Longevity Regulation.

Growth-regulating factors (GRFs) are plant-specific transcription factors that play an important role in plant growth and development. In this study, fifteen gene members containing QLQ and WRC domains were identified in . Phylogenetic and collinearity analysis showed that ZaGRFs were closely related to CsGRFs and AtGRFs, and distantly related to OsGRFs. There are a large number of cis-acting elements related to hormone response and stress induction in the gene promoter region of . Tissue-specific expression analysis showed that except for , all the were highly expressed in young parts with active growth and development, including terminal buds, seeds, and young flowers, suggesting their key roles in growth and development. Eight were selected to investigate the transcriptional response to auxin, gibberellin and drought treatments. A total of six in the NAA treatment, four in the GA treatment, and six in the PEG treatment were induced and significantly up-regulated. Overexpression of increased branching and chlorophyll content and delayed senescence of transgenic . increased the expression of and suppressed the expression of and , indicating that is involved in cytokinin metabolism and signal transduction. These research results lay a foundation for further analysis of the gene function of and provide candidate genes for growth, development, and stress resistance breeding of .