Genome-wide Characterization of GRAS Transcription Factors and Their Potential Roles in Development and Drought Resilience in Rose (Rosa chinensis)

Abstract In the past few years, plant-specific GRAS transcription factors (TFs) were reported to play an essential role in regulating several biological processes, such as plant growth and development, phytochrome signal, arbuscular mycorrhiza (AM) symbiosis, environmental stress responses. GRAS genes have been thoroughly studied in several plant species, but unexplored in Rosa chinensis (rose). In this study, 59 rose GRAS genes (RcGRAS) were identified. Phylogenetic analyses grouped RcGRAS genes into 17 subfamilies, of which subfamily Rc2 was Rosaceae family-specific. Gene structure analyses showed that most of the RcGRAS genes were intronless and were relatively conserved. Cis-element analyses suggested that RcGRAS genes may involve in distinct biological processes and responsive to diverse abiotic stresses. Most of the genes were localized in the nucleus, except for a few in the cytoplasm. Gene expression analysis was also performed in various tissues, during gibberellin (GA) and drought stress treatment. The expression patterns of RcGRAS genes during GA treatment and in response to drought stresses suggested the potential functions of these genes in regulating stress and hormone responses. In summary, a comprehensive exploration of the rose GRAS gene family was performed, and the generated information can be utilized for further functional-based studies on this family.