Objective This study aimed to clone and characterize the ShRPM1 gene from sugarcane to elucidate its molecular features and provide a valuable genetic resource for the molecular breeding of disease-resistant sugarcane varieties.

Method In this study, the full-length cDNA sequence of ShRPM1 was isolated via reverse transcription PCR (RT-PCR). Bioinformatics analysis was performed to characterize the physicochemical properties, conserved domains, and subcellular localization of the encoded protein, alongside the identification of cis-acting elements within the promoter region. Furthermore, the transcriptional response of ShRPM1 to stress induced by the sugarcane pokkah boeng pathogen was quantified using quantitative real-time PCR (qRT-PCR).

Result The ShRPM1 cDNA is 3 747 bp in length, encoding a 1 248-amino-acid polypeptide with a predicted molecular weight of 141.8 kDa and a theoretical isoelectric point (pI) of 8.62. ShRPM1 is characterized as a hydrophilic, non-secretory protein lacking transmembrane domains and is primarily localized to the nucleus. Conserved domain analysis identified RX-CC-like, NB-ARC, and LRR domains, assigning ShRPM1 to the CC-NBS-LRR (CNL)-type disease resistance protein subfamily. Phylogenetic analysis demonstrated that ShRPM1 shares high homology with its ortholog in Sorghum bicolor. Moreover, ShRPM1 exhibited distinct spatio-temporal expression features, with the highest transcript levels observed in the stem and at the seedling stage, respectively. Notably, the expression of ShRPM1 was significantly up-regulated at 24 hours post-inoculation (hpi) with the pokkah boeng pathogen, indicating a strong inductive response to fungal infection.

Conclusion In summary, the ShRPM1 gene was successfully cloned and characterized from sugarcane for the first time. Our findings demonstrate that ShRPM1 plays a pivotal role in the sugarcane defense response and represents a promising candidate gene for molecular breeding programs aimed at enhancing disease resistance.