Senescence-Associated Glycine max ( Gm ) NAC Genes: Integration of Natural and Stress-Induced Leaf Senescence

• Published in: International journal of molecular sciences 2021-08, Vol.22 (15), p.8287
• Main Authors: Fraga, Otto Teixeira, de Melo, Bruno Paes, Quadros, Iana Pedro Silva, Reis, Pedro Augusto Braga, Fontes, Elizabeth Pacheco Batista
• Format: Article
• Language: English
• Subjects: abiotic stresses; Aging; Apoptosis; Arabidopsis; Cell death; Cellular Senescence; Chlorophyll; Chloroplasts; Environmental effects; Gene expression; Gene Regulatory Networks; Genes; Genomes; Glycine max - physiology; GmNAC; Hormones; leaf senescence; Leaves; Metabolism; NAC transcription factors; PCD; Plant Leaves - physiology; Plant Proteins - genetics; Plant Proteins - metabolism; programmed cell death; Review; Senescence; Soybeans; Stress, Physiological; Trans-Activators - genetics; Trans-Activators - metabolism; Transcription factors
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms22158287

Leaf senescence is a genetically regulated developmental process that can be triggered by a variety of internal and external signals, including hormones and environmental stimuli. Among the senescence-associated genes controlling leaf senescence, the transcriptional factors (TFs) comprise a functional class that is highly active at the onset and during the progression of leaf senescence. The plant-specific NAC (NAM, ATAF, and CUC) TFs are essential for controlling leaf senescence. Several members of Arabidopsis are well characterized as players in elucidated regulatory networks. However, only a few soybean members of this class display well-known functions; knowledge about their regulatory circuits is still rudimentary. Here, we describe the expression profile of soybean upregulated by natural senescence and their functional correlation with putative orthologs. The mechanisms and the regulatory gene networks underlying and -positive regulation in leaf senescence are discussed. Furthermore, new insights into the role of as a negative senescence regulator are presented, demonstrating extraordinary functional conservation with the Arabidopsis counterpart. Finally, we describe a regulatory circuit which integrates a stress-induced cell death program with developmental leaf senescence via the NRP-NAC-VPE signaling module.