Aquaporin, Genome-wide identification, Mulberry, Plasma membrane intrinsic protein (PIP), Ralstonia pseudosolanacearum, Gene expression, Botany, QK1-989

Abstract Background Aquaporins (AQPs) play crucial roles in plant water transport, growth and development, and response to biotic and abiotic stresses. Despite their essential functions, the role of AQPs in mulberry trees (Morus L.) during Ralstonia pseudosolanacearum infection remains largely unknown. Results In this study, we performed a genome-wide identification and comprehensive characterization of AQP genes in Morus notabilis. A total of 26 AQP genes were identified and classified into four subfamilies: NIP, PIP, SIP and TIP. Furthermore, detailed analyses were conducted on gene structures, protein physicochemical properties, transmembrane domains, phylogenetic relationships, and subcellular localization. Cis-acting element analysis showed that MnAQP genes were mainly involved in hormone, light and stress response. Tissue-specific expression analysis demonstrated that the PIP1 subfamily displayed significantly higher transcript abundance in root tissues relative to leaves, while the PIP2 subfamily maintained relatively stable expression patterns across various tissue types. In addition, following R. pseudosolanacearum inoculation, the expression levels of PIP genes were significantly upregulated in the roots, stems, and leaves of mulberry seedlings. These findings indicate that MnPIP genes play a crucial role in responding to R. pseudosolanacearum infection. Conclusions This study provides the comprehensive characterization of the AQP gene family in mulberry, clarifying the composition and diversity. Our findings establish a solid foundation for further understanding the function roles of MnPIPs following R. pseudosolanacearum infection in mulberry trees. Clinical trial number Not applicable.