| Autor: |
Fraga OT; Biochemistry and Molecular Biology Department, Universidade Federal de Viçosa, Viçosa 36570.000, MG, Brazil.; National Institute of Science and Technology in Plant-Pest Interactions, INCTIPP-BIOAGRO, Universidade Federal de Viçosa, Viçosa 36570.000, MG, Brazil., de Melo BP; Biochemistry and Molecular Biology Department, Universidade Federal de Viçosa, Viçosa 36570.000, MG, Brazil.; Embrapa Genetic Resources and Biotechnology, Brasília 70770.917, DF, Brazil., Quadros IPS; Biochemistry and Molecular Biology Department, Universidade Federal de Viçosa, Viçosa 36570.000, MG, Brazil.; National Institute of Science and Technology in Plant-Pest Interactions, INCTIPP-BIOAGRO, Universidade Federal de Viçosa, Viçosa 36570.000, MG, Brazil., Reis PAB; Biochemistry and Molecular Biology Department, Universidade Federal de Viçosa, Viçosa 36570.000, MG, Brazil.; National Institute of Science and Technology in Plant-Pest Interactions, INCTIPP-BIOAGRO, Universidade Federal de Viçosa, Viçosa 36570.000, MG, Brazil., Fontes EPB; Biochemistry and Molecular Biology Department, Universidade Federal de Viçosa, Viçosa 36570.000, MG, Brazil.; National Institute of Science and Technology in Plant-Pest Interactions, INCTIPP-BIOAGRO, Universidade Federal de Viçosa, Viçosa 36570.000, MG, Brazil. |
| Abstrakt: |
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 AtNAC-SAGs 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 GmNAC-SAGs upregulated by natural senescence and their functional correlation with putative AtNAC-SAGs orthologs. The mechanisms and the regulatory gene networks underlying GmNAC081- and GmNAC030 -positive regulation in leaf senescence are discussed. Furthermore, new insights into the role of GmNAC065 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. |
