枳丛枝菌根共生相关硝酸盐转运蛋白基因PtNPF5.2的功能鉴定OA

To investigate the molecular mechanism of nitrate(NO3-)transport via the arbuscular mycorrhiza(AM)pathway in citrus,this study used Poncirus trifoliata,a common citrus rootstock,to examine the expression pattern and subcellular localization of the NO3-transporter gene PtNPF5.2,as well as the role of its homologous genes in the AM symbiosis of the model plants Medicago truncatula and Solanum lycopersicum.The results showed that PtNPF5.2 was specifically induced by arbuscular mycorrhizal fungi(AMF),its promoter was activated in root cells containing arbuscules,and the encoded protein was localized to the plasma membrane.Interference or insertion mutation of the homologous gene MtNPF5.3 in Medicago truncatula did not affect AMF colonization.Similarly,CRISPR/Cas9 knockout of the homologous gene SlNPF5.2 in Solanum lycopersicum did not affect AMF colonization but led to a significant decrease in shoot NO3-content.In summary,PtNPF5.2 may be involved in regulating the NO3-allocation within the plant during AM symbiosis in Poncirus trifoliata,providing insights into the nitrogen transport mechanisms via the AM pathway in citrus.