Vitis amuerensis CBF3 Gene Isolation, Sequence Analysis and Expression

The full length cDNA sequence of CBF3 (CRT/DRE-binding factor) was cloned from Vitis amurensis by reverse transcription polymerase chain reaction (RT-PCR) using the primers designed based on CBF genes available in GenBank. Sequence analysis showed that the gene had 854 bp long and its coding sequence contained 720 bp, encoding a protein with 239 amino acids and an AP2 structural domain. The molecular mass of CBF3 was predicted to be 25.9 kDa and its theoretical isoelectric point was 7.02 and aliphatic index was 59.29. The average hydropathicity of the protein was −0.551. The tertiary structures of CBF3 were also analyzed. The prokaryotic expression vector pGEX-4T-CBF3 containing CBF3 gene was constructed and CBF3 fusion protein (52 kDa) was produced in Escherichia coli after induction with 1 mmol L−1 IPTG. Further studies are needed to evaluate its potential application for improving plant resistance to cold and other stress condition such as drought and salinity.