Abstract: NUDIX hydrolase belongs to pyrophosphatase, which plays an important role in information transmission, plant growth coordination and responses to adversity stresses. In this study, 43 NUDIX family genes were identified based on the tea (Camellia sinensis) genome, and analyzed by bioinformatics and fluorescence quantitative PCR. The results show that the protein molecular weight of 43 CsNUDXs rang from 11.8~89.2 kDa, with 102 to 342 amino acids. The theoretical isoelectric point was from 4.49 to 9.26, and 18.6% of them were stable proteins. According to the evolutionary relationship, CsNUDXs is divided into six subfamilies. Cis-acting element analysis of promoter shows that CsNUDXs have many functional elements related to hormone response, adversity stress, growth and development. The expression patterns of CsNUDXs in different organs were analyzed. It was found that the expression levels of CsNUDX3 and CsNUDX7 were high in fruits, while the expression levels of CsNUDX22 and CsNUDX25 were extremely low in fruits, and the expression level of CsNUDX30 was extremely low in old leaves. In addition, the results of real-time fluorescence quantitative PCR show that the expression levels of CsNUDXs, such as CsNUDX1, CsNUDX2 and CsNUDX33 increased first, then decreased and then increased under the treatment of 1 mmol·L^-1 MeJA. However, under the treatment of 1 mmol·L^-1 SA, the expression levels of CsNUDX4, CsNUDX12 and CsNUDX22 decreased first, then increased and then decreased. While under the treatment of 300 mmol·L^-1 NaCl, the expression levels of CsNUDX2, CsNUDX4 and CsNUDX22 increased first and then decreased. In summary, the basic characteristics and functions of CsNUDXs were preliminarily analyzed by bioinformatics technology, and it was found that CsNUDXs could respond to high salt stress, MeJA and SA treatments.

Key words: Camellia sinensis, NUDIX gene family, abiotic stress, expression analysis