Abstract:For exploring Hippophae rhamnoides L., using RACE and RTqPCR technique, we cloned phosphoenolpyruvate carboxykinase (PEPCK) gene. The sequence analysis was performed to determine the homology, phylogenetic tree and secondary structure for PEPCK protein in H. rhamnoides L., compare the expression differentiation of PEPCK under NaCl stress. This study laid the foundation in order to reveal the function of PEPCK gene resistant to salt stress in H. rhamnoides L. The results indicated that: (1) the open reading frame (ORF) of H. rhamnoides L. was 2 001 bp, and 666 amino acids were encoded. (2) Sequence analysis showed that the consistency of H. rhamnoides L. was as high as 85% with Ricinus communis, Flaveria pringlei and Juglans regia and the evolution relationship of PEPCK is relatively close to that of R. communis and Lupinus angustifolius, far from Nicotiana tabacum and Arabidopsis thaliana. (3) Under 300 mmol·L-1 NaCl stress, PEPCK gene expression of H. rhamnoides L. increased significantly in the stress group with 2.5 times higher than that of normal group at 7th day, and 3.2 times higher at 15th day, which showed a significant rise in PEPCK gene expression under salt stress. Our study showed that the complete coding sequence of PEPCK gene in H. rhamnoides L. was successfully cloned, and PEPCK gene may play an important role in the process of adaptation exogenous salt stress. The result has laid a theoretical basis for revealing the molecular mechanism of H. rhamnoides L. in resistance to salt stress.