Abstract: In this study，the homologous gene CsRBOHA was isolated from tea plant（Camellia sinensis）by RACE and RT-PCR. The full length of CsRBOHA gene（GenBank Accession No. KJ782632）was 3 157 bp，which had an open reading frame of 2 769 bp，encoding 922 amino acids. The molecular weight of the predicted enzyme was 103.33 kD and the pI value was 9.28. Homologous alignment showed that the predicted CsRBOHA protein was similar to Nicotiana tabacum and Ricinus communis，with the similarity of 79%. CsRBOHA was conserved with NADPH oxidase superfamily. Subcellular localization indicated that the protein was localized in plasma membrane，which is identical to the predicted results. Quantitative real-time PCR showed that the gene was tissue-specific and up-regulated by low temperature，NaCl（200 nmol ? L-1），ABA（200 mg ? L-1）and 10% PEG 6000 at different degree.

Key words: tea plant, NADPH oxidase, gene cloning, subcellular localization, qRT-PCR, expression analysis