Gibberellic Acid-Stimulated Arabidopsis (GASA) proteins are cysteine-rich peptides broadly conserved in plants and implicated in growth regulation, stress adaptation, and hormone signaling. Here, we identified 13 GASA genes in the maize genome, distributed across six chromosomes. Comprehensive analyses of their physicochemical properties, subcellular localization, and structural features classified them into three conserved clades. Promoter cis-element analysis suggested roles in developmental regulation, phytohormone responses, abiotic stress adaptation, and light signaling. Comparative synteny revealed close evolutionary relationships between maize and sugarcane GASA genes, implying divergence from a common ancestor. Transcriptomic and qRT-PCR analyses demonstrated that maize GASA genes exhibit tissue-specific and stress-responsive expression under low-phosphorus condition, with ZmGASA06 showing pronounced responsiveness to low-phosphorus stress. This study provides novel insights into the evolutionary dynamics and potential functional roles of the GASA family in maize, laying a foundation for further functional and molecular breeding studies.

CCCH-type zinc finger proteins (C3H transcription factors) play essential roles in plant growth, development, and responses to environmental stresses. Although several maize (Zea mays L.) C3H genes have been reported, a comprehensive genome-wide analysis based on the updated maize reference genome remains lacking. In this study, 64 C3H gene family members were systematically identified from the maize reference genome (Zm-B73-REFERENCE-NAM-5.0) and designated as ZmC3H01 to ZmC3H64 according to their chromosomal locations. Phylogenetic analysis classified the ZmC3H family into four distinct subgroups, exhibiting conserved yet subgroup-specific motif compositions. Synteny analysis revealed that segmental duplication events played an important role in the expansion and evolution of the ZmC3H gene family. Cis-acting regulatory element analysis suggested that ZmC3H genes may participate in multiple stress-responsive and developmental regulatory pathways. Furthermore, transcriptome analysis and quantitative real-time PCR (qRT-PCR) validation identified five candidate ZmC3H genes (ZmC3H33, ZmC3H36, ZmC3H39, ZmC3H52, and ZmC3H57) that exhibited differential expression under low-phosphorus and high-nitrogen conditions in the maize inbred lines 082, Ye107, and B73. These genes were selected based on their differential expression under nutrient stress and their representative distribution across phylogenetic subfamilies, providing preliminary candidates for further functional investigation. Subcellular localization and yeast transcriptional activation assays demonstrated that ZmC3H33, ZmC3H36, and ZmC3H57 are nuclear-localized proteins with transcriptional activation activity. Furthermore, dual-luciferase assays showed that all three proteins activated the maize Phosphate Starvation Response 1 (ZmPHR1) promoter, with ZmC3H57 exhibiting the strongest activation effect, suggesting that these ZmC3H proteins may act as potential upstream regulators of ZmPHR1-mediated low-phosphorus responses. Collectively, these findings provide valuable insights into the evolutionary characteristics and potential biological functions of the maize C3H gene family and identify putative candidate genes for improving phosphorus-use efficiency.