茶树NAC转录因子家族的鉴定及生物信息学分析

Identification and Bioinformatics Analysis of NAC Transcription Factor Family in Tea Tree(Camellia sinensis L.)

利用生物信息学手段对茶树NAC转录因子家族的成员、系统发育、编码蛋白的理化性质和结构以及创伤胁迫处理后的表达进行分析.研究结果显示,茶树NAC转录因子家族包含49个成员,与拟南芥的106个NAC成员构建系统发育进化树,结果显示,茶树缺乏拟南芥NAC家族17个亚族中的第10和第14两个亚族.理化性质和结构分析显示茶树NAC蛋白质绝大多数是亲水氨基酸,二级结构以无规则卷曲为主,三级结构大部分相似.保守基序分析表明,茶树NAC成员共包含7个保守基序,其中基序3、4、2和5、1分别代表NAC结构域的A、B、C和D亚结构域,而基序7表示的是亚结构域E.第15,16和17亚族的大部分成员都缺失了第2和第4两个保守基序,而第15亚族成员具有一个特异的保守基序6.在机械创伤处理条件下表达模式分析表明,第11亚族的CsNAC33和CsNAC34两个成员虽然具有不一样的蛋白结构域组成,但在应对创伤处理时呈现相对一致的表达模式,而16亚族的CsNAC47和CsNAC48两个成员具有一致的蛋白结构域组成,但其表达模式出现分化.上述结果为后续进行茶树NAC基因家族功能的研究提供了理论依据.

NAC gene family is one of the largest plant-specific transcription factor families, which plays significant roles in plant development processes and stress responses. In this study, by utilizing the bioinformatics method, we performed comprehensive analysis on Camellia sinensis NAC transcription factor family, including identification of the members, phylogenetic analysis, physical and chemical properties and structure analysis of proteins, and expression analysis of the wound response. The results show that NAC transcription factor family contain 49 predicted proteins in tea and can be clustered into seventeen subfamilies. The physical and chemical properties and structure analysis reveal that the majority of proteins are hydrophilic. The secondary structure of 49 predicted NAC proteins is mainly random coil, and the tertiary structure is similar. The motifs analysis shows that the NAC members of the tea plant contain 7 conserved motifs, among which motif three, four, two and five, one represent the A, B, C and D subdomains of NAC domain, and motif seven is the subdomain E, respectively. Most members of the 15, 16 and 17 subgroups are lacking in second and fourth conserved motifs, while the 15 subgroup specific have a conserved motif six. The expression patterns of wound response show that in 11 subgroups, CsNAC33 and CsNAC34, with different constitutions of motif show relatively conservative response to injury treatment. In 16 subgroup, CsNAC47 and CsNAC48, exhibit the same constitutions of motif, but their expression patterns appear divergence. The results could provide valuable information for the follow-up study on the function of NAC gene family in Camellia sinensis.