植物水通道蛋白介导的"水-肥-气"跨膜运输功能的研究进展及展望OA

[Significance]Plant aquaporins(AQPs)are not only key channels for transmembrane water transport but also facilitate the transport of urea,NH3,CO2,and other nutrients and gases,serving as crucial molecular nodes linking water,nutrient,and gas exchange in plants.However,the systemic integration mechanisms of AQPs in coor-dinated water-nutrient-gas transport have not been comprehensively summarized,limiting an in-depth understanding of crop resource use efficiency and stress regulatory networks.Therefore,systematically elucidating the multifunc-tional specialization,tissue localization,and dynamic regulation of AQPs is of great theoretical and applied significance for revealing the molecular basis of integrated water-nutrient-gas transport in plants.[Progress]Based on a compara-tive genomic analysis of 2 134 AQP family members identified from 51 plant genomes,combined with evidence from Xenopus oocyte and yeast heterologous expression systems and genetic and physiological studies in Arabidopsis,rice,maize,and other plants,it has been established that AQP family size is driven by both whole-genome polyploidization and habitat adaptation.In drought-tolerant species,the PIP and TIP subfamilies are significantly expanded;NIPs are markedly enriched in legumes;and XIPs are completely lost in grasses and certain other lineages.Structurally,the central hydrophobic pore of the AQP tetramer is the preferential diffusion pathway for CO2,whereas the monomeric NPA pore is responsible for the transport of water,urea,and other small molecules.Functionally,plasma mem-brane-localized PIPs coordinate water uptake and photosynthetic CO2 supply;tonoplast-localized TIPs participate in urea storage and H2O2 detoxification;and NIPs mediate root uptake of urea,NH3,boron,and silicon.Phosphorylation acts as a core switch for dynamic coordination:phosphorylation of AtPIP2;1 by AtOST1/AtBAK1 can simultaneously enhance stomatal CO2 conductance and water transport efficiency.Under drought stress,ABA signaling closes water channels while maintaining CO2 permeability through the central pore,thereby achieving water conservation while sustaining carbon assimilation.Overexpression of OsPIP1;3,ZmPIP2;5,and other genes significantly improves plant water use efficiency,nitrogen uptake,and net photosynthetic rate.Taken together,through subfamily functional spe-cialization and dynamic regulation such as phosphorylation,plant AQPs constitute molecular hubs of an integrated water-nutrient-gas transport network.[Prospect]Future studies should further integrate cryo-electron microscopy,molecular dynamics simulations,and single-cell spatiotemporal omics to dissect AQP substrate selectivity,gating mechanisms,and their fine regulatory networks at cellular and organ scales.Meanwhile,precision engineering of key PIP,TIP,and NIP members through gene editing and synthetic biology should be strengthened to create crop germplasm with coordinated high water-nutrient-gas use efficiency and enhanced stress tolerance,thereby promoting the translation of AQP functional studies from model plants to breeding applications in major crops.