摘要: This study aimed to clone the full-length and coding sequences of violaxanthin de-epoxidase(VDE) gene in Nicotiana tabacum, and to investigate its genetic characteristics and functions in photoinhibition. According to expressed sequence tags, the full-length and coding sequences of NtVDE were homologously cloned from Nicotiana tabacum. Gene sequences were analyzed by bioinformatic softwares. NtVDE copies were determined by capillary electrophoresis. Expression patterns of NtVDE in different organs and photoinhibition conditions were examined by fluorescent and quantitative PCR. Two copies of NtVDE, namely NtVDE1 and NtVDE2, were cloned from cultivated tobacco. Results of phylogenetic analysis showed that NtVDE1 and NtVDE2 originated from Nicotiana sylvestris and Nicotiana tomentosiformis, respectively. The expression level of NtVDE was the highest in leaves and induced by photoinhibition. NtVDE1 and NtVDE2 showed different expression patterns in PVY infection. There are at least two copies of NtVDE in Nicotiana tabacum genome and they probably play different roles in stress resistance in the tobacco.