Natural and Medicinal Plant Sciences Research Center, University of Nizwa, Nizwa, Oman.
Dept. of Medical Biotechnology, Yeungnam University, Gyeongsan, Republic of Korea.
PLoS One. 2020 Apr 10;15(4):e0231425. doi: 10.1371/journal.pone.0231425. eCollection 2020.
NAC (NAM, ATAF1,2, and CUC2) transcription factors are one of the largest transcription factor families found in the plants and are involved in diverse developmental and signalling events. Despite the availability of comprehensive genomic information from diverse plant species, the basic genomic, biochemical, and evolutionary details of NAC TFs have not been established. Therefore, NAC TFs family proteins from 160 plant species were analyzed in the current study. Study revealed, Brassica napus (410) encodes highest number and Klebsormidium flaccidum (3) encodes the lowest number of TFs. The study further revealed the presence of NAC TF in the Charophyte algae K. flaccidum. On average, the monocot plants encode higher number (141.20) of NAC TFs compared to the eudicots (125.04), gymnosperm (75), and bryophytes (22.66). Furthermore, our analysis revealed that several NAC TFs are membrane bound and contain monopartite, bipartite, and multipartite nuclear localization signals. NAC TFs were also found to encode several novel chimeric proteins and regulate a complex interactome network. In addition to the presence of NAC domain, several NAC proteins were found to encode other functional signature motifs as well. Relative expression analysis of NAC TFs in A. thaliana revealed root tissue treated with urea and ammonia showed higher level of expression and leaf tissues treated with urea showed lower level of expression. The synonymous codon usage is absent in the NAC TFs and it appears that they have evolved from orthologous ancestors and undergone vivid duplications to give rise to paralogous NAC TFs. The presence of novel chimeric NAC TFs are of particular interest and the presence of chimeric NAC domain with other functional signature motifs in the NAC TF might encode novel functional properties in the plants.
NAC（NAM、ATAF1、2 和 CUC2）转录因子是植物中最大的转录因子家族之一，参与多种发育和信号事件。尽管来自不同植物物种的综合基因组信息已经可用，但 NAC TF 的基本基因组、生化和进化细节尚未确定。因此，本研究分析了来自 160 种植物的 NAC TF 家族蛋白。研究表明，甘蓝型油菜（410）编码的 TF 数量最多，而软枝黄蝉（3）编码的 TF 数量最少。研究还表明，NAC TF 存在于轮藻门藻类软枝黄蝉中。平均而言，单子叶植物编码的 NAC TF 数量（141.20）高于双子叶植物（125.04）、裸子植物（75）和苔藓植物（22.66）。此外，我们的分析表明，一些 NAC TF 是膜结合的，并且包含单部分、双部分和多部分核定位信号。还发现 NAC TF 编码几种新的嵌合蛋白，并调节复杂的相互作用网络。除了存在 NAC 结构域外，还发现几种 NAC 蛋白编码其他功能特征基序。拟南芥 NAC TF 的相对表达分析表明，用尿素和氨处理的根组织表现出较高的表达水平，而用尿素处理的叶片组织表现出较低的表达水平。NAC TF 中不存在同义密码子使用，它们似乎是从同源祖先进化而来，并经历了生动的复制，产生了旁系同源的 NAC TF。新型嵌合 NAC TF 的存在特别有趣，并且在 NAC TF 中 NAC 结构域与其他功能特征基序的存在可能编码植物中的新功能特性。
