Kim Taehoon, Alvarez Javier C, Rana Divya, Preciado Jesus, Liu Tie, Begcy Kevin
Environmental Horticulture Department, University of Florida, PO Box 110670, Gainesville, FL 32611, USA.
School of Applied Sciences and Engineering, EAFIT University, PO Box 98873, Medellin 050022, Colombia.
Plant Cell Physiol. 2025 May 17;66(4):566-580. doi: 10.1093/pcp/pcae133.
NAC [NO APICAL MERISTEM (NAM), ARABIDOPSIS TRANSCRIPTION ACTIVATOR FACTOR 1/2 (ATAF1/2), and CUP-SHAPED COTYLEDON (CUC2)] transcription factors are key regulators of plant growth, development, and stress responses but were also crucial players during land plant adaptation and crop domestication. Using representative members of green algae, bryophytes, lycophytes, gymnosperms, and angiosperms, we expanded the evolutionary history of NAC transcription factors to unveil the relationships among members of this gene family. We found a massive increase in the number of NAC transcription factors from green algae to lycophytes and an even larger increase in flowering plants. Many of the NAC clades arose later during evolution since we found eudicot- and monocot-specific clades. Cis-elements analysis in NAC promoters showed the presence of abiotic and biotic stress as well as hormonal response elements, which indicate the ancestral function of NAC transcription factor genes in response to environmental stimuli and in plant development. At the transcriptional level, the expression of NAC transcription factors was low or absent in male reproduction, particularly mature pollen, across the plant kingdom. We also identified NAC genes with conserved expression patterns in response to heat stress in Marchantia polymorpha and Oryza sativa. Our study provides further evidence that transcriptional mechanisms associated with stress responses and development emerged early during plant land adaptation and are still conserved in flowering plants and domesticated crops.
NAC（无顶端分生组织（NAM）、拟南芥转录激活因子1/2（ATAF1/2）和杯状子叶（CUC2））转录因子是植物生长、发育和应激反应的关键调节因子，也是陆地植物适应和作物驯化过程中的重要参与者。利用绿藻、苔藓植物、石松类植物、裸子植物和被子植物的代表性成员，我们扩展了NAC转录因子的进化史，以揭示该基因家族成员之间的关系。我们发现从绿藻到石松类植物，NAC转录因子的数量大幅增加，而在开花植物中增加得更多。由于我们发现了双子叶植物和单子叶植物特有的进化枝，许多NAC进化枝是在进化后期出现的。对NAC启动子的顺式元件分析表明，存在非生物和生物胁迫以及激素反应元件，这表明NAC转录因子基因在响应环境刺激和植物发育方面的祖先功能。在转录水平上，NAC转录因子在整个植物界的雄性生殖中，特别是在成熟花粉中，表达较低或不存在。我们还在多岐鹿角菜和水稻中鉴定出了对热胁迫具有保守表达模式的NAC基因。我们的研究提供了进一步的证据，表明与应激反应和发育相关的转录机制在植物陆地适应早期就已出现，并且在开花植物和驯化作物中仍然保守。
