摘要
Na+/H+ antiporters play an important role in the salt tolerance of a wide variety of plants.Using the rapid amplification of cDNA ends method,a Na+/H+ antiporter gene (PeNHX1) was isolated from Populus euphratica.The deduced amino acid sequence contained 528 amino acid residues with a conserved amiloride-binding domain (77LFFIYLLPPI86) and shared more than 68% identity with that of AtNHX1 from Arabidopsis thaliana.PeNHX1 can confer resistance to Na+,as well as Li+,to (EP432) an Escherichia coli strain deficient in both nhaA and nhaB,thus proving that it is a functional Na+/H+ antiporter.PeNHX1 expression profile in EP432 reflected pH independent manner.PeNHX1 expression was regulated by salt at the transcriptional level.Meanwhile,results demonstrated that transcripts of PeNHX1 in P.euphratica calli showed a salt dependent response,and thus provide a valuable tool for studying signaling and biochemical pathways involved in salt recognition and response in P.euphratica.
基金
Financial support for this research was provided by NSFC (30800865)
China Postdoctoral Science Foundation (200704207)
