Abstract: A cDNA sequence of cytosolic 6-phosphogluconate dehydrogenase（6PGDH）gene was cloned from Nicotiana tabacum by in silico cloning combined with RT-PCR and SMART RACE technologies, and designated as Nt6PGDH（Accession number KM211534）. The full length of its cDNA sequence is 1 932 bp, with a 1 455 bp open reading frame, and the gene encoded a protein of 484 amino acids with the sequence of highest identity, 95% as 6PGDH from Solanum lycopersicum and Solanum tuberosum. Bioinformatics analysis indicated that Nt6PGDH had no signal peptide, no transit peptide and notrans-membrane domain, and it was located in cytoplasm. Gene expression analysis showed that the expression levels of Nt6PGDH in roots, stems and leaves were higher at fast-growirg stage than at seedling stage. Moreover, at the same developmental stage, the highest level of Nt6PGDH expression were in the roots, then in the stems, the lowest in the leaves.

Key words: Nicotiana tabacum, cytosolic glucose-6-phosphate dehydrogenase, gene cloning, expression analysis