Genome-Wide Identification and Characterization of GRAS Transcription Factor Family in Cultivated Hybrid Sugarcane ZZ1 (Saccharum officinarum) and Their Role in Development and Stress

GRAS gene family plays multifunctional roles in plant growth, development, and resistance to various biotic and abiotic stresses, belonging to the plant-specific transcription factor (TF) family. In this study, a genome-wide survey and systematic analysis of the GRAS family in cultivated hybrid sugarcane ZZ1 (Saccharum officinarum) with economic and industrial importance was carried out. We identified 747 GRAS genes with complete structural domains and classified these into 11 subfamilies by phylogenetic analyses, exhibiting a diverse range of molecular weight and isoelectric points, thereby indicating a broad structural and functional spectrum. Analysis of Protein motif and gene structure revealed a conserved yet variable arrangement of motifs within the GRAS TFs, suggesting its potential for diverse functional roles. Furthermore, the identification of numerous cis-regulatory elements by GRAS TFs promoter sequence analysis, implying their complex regulation in response to environmental and physiological signals. Tertiary structure predictions analyses using AlphaFold3 highlighted the structural flexibility and conservation within the GRAS family, with disordered regions potentially contributing to their functional versatility. Weighted Gene Co-expression Network Analysis (WGCNA) provided insights into the potential roles of ShGRAS21A in sugarcane's response to smut infection. This comprehensive investigation of the GRAS family in ZZ1 not only uncovers their structural diversity but also sheds light on their potential regulatory roles in plant growth, development, and stress response. The findings contribute to a deeper understanding of GRAS TFs functions and lay the groundwork for future studies on their role in sugarcane improvement and disease resistance.