Abstract: Abiotic stress severely affects the growth and development of tea plant and the quality of tea. ASR (abscisic acid, stress, ripening) genes play crucial roles in the plant response to stresses. The full-length cDNA, genomic sequence and the promoter sequence of CsASR gene were cloned from tea cultivar Longjing 43 in this study, The bioinformatic and the expression analysis of CsASR in tissues under different stress treatments were performed. The results revealed that the full-length cDNA of CsASR was 875βbp, containing a 546βbp ORF encoding 181 amino acid. The predict protein molecular and theoretic isoelectric point of CsASR were 19.89βkD and 5.69. Most regions of the amino acid sequence (74.5%) were predicted as the non-ordered regions, indicating that CsASR is a disordered protein. C-terminal of CsASR contained an ABA/WDS functional domain which was primarily located in both the cytoplasm and the nucleus. The homologous alignment and phylogenetic tree analysis showed that CsASR had the highest similarity (87%) with Phoenix dactylifera, and had the closest genetic relationship with Ziziphus nummularia. The genomic sequence of CsASR gene was comprised by two exons with 363 bp and 183 bp in length, respectively, and had a 2 750 bp intron which contained seven simple repeats and two DNA transposons. The promoter sequence of CsASR was 2 554 bp in length and was predicted to contain several stress-responsive elements related to drought, cold, high temperature stresses and ABA-signaling. The expression analysis showed that CsASR had the lowest level in roots, and its expression was repressed by ABA treatment. While the drought, NaCl and cold stresses could significantly up-regulate the expression of CsASR. The results revealed that CsASR might be closely related to stress response in tea plant.

Key words: tea plant, ASR gene, abiotic stress, gene cloning