Abstract: In this experiment，a CIPK gene was cloned from tea plant（Camellia sinensis）cultivar‘Longjing 43’by RT-PCR，and named CsCIPK. Sequence analysis showed that the open reading frame of CsCIPK is 1 341 bp and encoded 446 amino acids with molecular weight of 414 234. The prediction of protein functional domain showed that the CsCIPK protein contains a conserved N-terminal kinase domain and a relatively unconserved C-terminal regulatory domain，namely the serine/threonine kinase domain and the NAF domain. CsCIPK is a hydrophobic protein and theoretical pI is 7.04. CsCIPK contains four unordered regions，and mainly composed of α-helix and irregular coils. The expression profile of CsCIPK gene in tea plant cultivars‘Longjing 43’and‘Anjibaicha’was analyzed by real-time quantitative PCR. The results showed that the relative expression of CsCIPK in‘Longjing 43’reached its highest level at high temperature，drought，salt treatment for 4 h，and low temperature treatment for 24 h. The relative expression of CsCIPK in‘Anjibaicha’was highest at high temperature and salt treatment for 4 h，and at low temperature and drought treatment for 1 h. In different tea tree tissues，the expression of CsCIPK was highest in the root of‘Longjing 43’，and in the stem of‘Anjibaicha’. Different concentrations of GA and IBA treatment showed that the expression level first increased and then decreased under 0.2 mmol ? L-1 GA，and reached the highest level at 6 days. After treatment with 0.6 mmol ? L-1 IBA，the expression level was significantly higher than the control at 3 days. After treatment with different concentrations of different hormones，the expression level of CsCIPK on the 9 days in the treatment was significantly lower than the control.

Key words: Camellia sinensis, protein kinase, CsCIPK, tissue expression, abiotic stress, hormonal treatment