高州油茶NAC转录因子家族鉴定及生物信息学分析

Identification and Bioinformatics Analysis of NAC Transcription Factor Family in Camellia drupifera Loureiro

NAC转录因子是植物中特有的转录因子,其在N端含有一段高度保守的特异结构域,对植物生长发育、胁迫反应和次生代谢产物生物合成等过程具有重要功能。研究基于高州油茶第三代全长转录组数据信息,通过生物信息学的方法筛选获得51个NAC转录因子,为深入研究基因家族特征,对其进行理化性质分析、多列比对分析、蛋白系统进化树、保守基序和基因结构分析、亚细胞定位,以及二级蛋白域结构预测、蛋白磷酸化位点分析。结果表明:NAC蛋白存在氨基酸数量差异,且氨基酸序列间疏水性呈现为亲水性蛋白,其蛋白结构中具有5个保守的亚结构域。NAC转录因子系统进化树分析表明116个基因可划分为10个亚族群,部分高州油茶NAC蛋白具有特异性聚为单一亚族群,其他与拟南芥和水稻融合为不同亚族群。同时NAC蛋白均具有NAM超家族结构。亚细胞定位表明51个高州油茶NAC蛋白均位于细胞核,且二级结构中随机卷曲结构为主,同时含有α-螺旋和β-转角结构等。蛋白磷酸化位点都具有丝氨酸(Ser)、苏氨酸(Thr)和酪氨酸(Tyr)。

NAC transcription factors are unique transcription factors in plants,which contain a highly conserved segment of specific structural domains at the N-terminus and have important functions in the processes of plant growth and development,stress response,and secondary metabolite biosynthesis.In this study,based on the information of the third-generation full-length transcriptome data of Camellia drupifera Loureiro(C.drupifera),51 NAC transcription factors were obtained by bioinformatics screening.In order to study the characteristics of these gene families,their physicochemical properties were analyzed,and multilinear comparison,protein phylogenetic trees,conserved motifs,gene structure,and subcellular localization were investigated.The structure of the secondary protein domains was predicted,and the protein phosphorylation sites were analyzed.The results show that NAC proteins differ in the number of amino acids,and the hydrophobicity between amino acid sequences is presented as hydrophilic proteins.Their protein structures have five conserved sub-structural domains.The phylogenetic tree analysis of the NAC transcription factors shows that 116 genes can be classified into 10 sub-populations.Part of the NAC proteins of C.drupifera is clustered as a single sub-population with specificity,and the other parts of the NAC proteins are fused with Arabidopsis thaliana and rice as a mixed sub-population.Meanwhile,all the NAC proteins have NAM superfamily structures.The subcellular localization shows that all 51 NAC proteins of C.drupifera are located in the nucleus,and the secondary structure is dominated by a randomly curled structure,with the structures ofα-helix andβ-rotor present.All the protein phosphorylation sites contain serine(Ser),threonine(Thr),and tyrosine(Tyr).The gene family characteristics of NAC transcription factors from C.drupifera provide a reference for the subsequent research on their gene functions.