Genome-wide identification of the ZmNUDX gene family and its response to biotic stress in maize

NUDX (nucleoside diphosphates linked to moiety X hydrolases) hydrolases are a class of highly conserved pyrophosphatases that play important roles in plant stress responses and immune regulation. To comprehensively characterize the structural features of the ZmNUDX gene family and their potential roles in disease resistance, we identified a total of 36 ZmNUDX members using bioinformatics approaches. These genes were widely distributed across all 10 maize chromosomes, with several showing significant collinearity. Subcellular localization predictions indicated that ZmNUDX proteins are mainly localized in the cytoplasm, plastids, mitochondria, and peroxisomes, suggesting potential multifunctionality. Promoter analysis revealed that cis-acting elements such as STRE, ABRE, MYB, MYC, and G-box are highly enriched in most genes, implying broad regulatory potential in hormone signaling and stress responses. Transcriptome analysis showed that several ZmNUDX genes were significantly induced under stem rot and maize smut stresses, with differential expression patterns observed between resistant and susceptible varieties, indicating their potential roles in disease defense. Furthermore, RT-qPCR validation of nine representative genes demonstrated that ZmNUDX-2 , ZmNUDX-9, ZmNUDX-15 , and ZmNUDX-25 exhibited significant responses under both stem rot ( Fusarium graminearum ) and maize smut ( Sphacelotheca reiliana ) treatments, whereas ZmNUDX-28 showed a dynamic pattern of downregulation followed by upregulation. Collectively, this study systematically elucidates the evolutionary and structural characteristics of the ZmNUDX gene family and highlights their differential expression patterns under biotic stress, providing theoretical insights and potential genetic resources for further functional characterization of NUDX genes and maize disease resistance breeding. • In this study, 36 ZmNUDX genes were identified across the maize genome using bioinformatics approaches. • ZmNUDX promoters were enriched with diverse stress-related cis-elements, especially STRE, ABRE, MYB, and MYC. • Transcriptome and RT-qPCR analyses identified ZmNUDX-2 , ZmNUDX-9 , ZmNUDX-15 , and ZmNUDX-25 as strongly induced genes, while ZmNUDX-28 showed dynamic expression under both pathogen stresses.