Cloning of TaPRP from Wheat and Its Cold Tolerance Analysis in Transgenic Tobacco

TaPRP, a proline rich protein (PRP) cDNA, was cloned by RT-PCR from winter wheat. Nucleotide sequence analysis showed TaPRP is composed of 1137 bp (378 amino acid residues with a Mr of 42.19 kD). TaPRP shows 92.6%, 89.3%, 73.0%, and 73.3% sequence homologies with PRP genes from wheat, sorghum, rice, and maize, respectively. The deduced protein includes 170 prolines, presenting a normal PRP primary structure. Expression vector pBI-TaPRP was constructed, in which TaPRP was driven by CaMV35S promoter and stopped by NospolyA. Tobaccos were transformed by Agrobacterium containing the constructed vectors. Three transgenic lines were confirmed by PCR detection and Southern blot. Under the same low temperature stress conditions, transgenic plants had lower conductivity rate compared with the non-transgenic plants, suggesting that cold tolerance in transgenic tobacco plants was improved. However, the different transgenic plants showed significant differences in cold resistant, and there also existed significant interactions between plant and treatment temperature. TaPRP might have an important role in wheat in cold adaptation process.