Objective  Expression of tea ZFP2 in tobacco plants in response to drought stress was studied to elucidate the molecular mechanism.

  Method   A zinc finger protein (ZFP) was previously found in our laboratory to interact with the promoter region of F3'5'H gene. Using bioinformatics methods, the structure of ZPF2 from Camellia sinensis was predicted and analyzed. Then, CsZFP2 was cloned and transferred into tobacco by an Agrobacterium-mediated method for functional verification under a simulated drought stress.

  Result  The domain of the ZFP from C. sinensis XM_028257969.1 was 68.57% homologous to that from Nicotiana tabacum XP_016463943.1. There were 13 introns in CsZFP2 with a length of 1,233a, a molecular weight of 141 204.45, an isoelectric point of pH 5.9, and an isoelectric point Pi＜7 indicating high content of acidic amino acids. The gene encoded mainly two proteins with an α-helix primary structure and a random coil 3D structure composed of α-helix and β-turn. The hydrophilic protein was subcellularly located in the nucleus with more than 50% of the amino acids having a sequence less than zero. Under natural drought for 28 d, the old leaves at the bottom of both wild-type and transgenic tobacco plants were turning yellow. However, those leaves on the wild-type plants became basically chlorotic and withered, but those on the transgenic plants wilted only slightly and largely remained green in color.

  Conclusion  CsZFP2 affected the response of tobacco plants to drought stress. The transgenic plants with overexpressed CsZFP2 were more resistant to the stress than the wild-type counterparts.