Transcription factors-regulated leaf senescence in major crops: Insights, applications, and challenges

Leaf senescence, the final stage of leaf development, is a complex biological process characterized by the degradation of macromolecules and nutrient redistribution. This process significantly contributes to plant fitness and adaptability. Senescence is regulated at multiple levels, including chromatin remodeling, transcription, post-transcription, translation, and post-translational modifications. Transcription factors play a pivotal role in regulating leaf senescence, with NAC and WRKY families being the most extensively studied. This review comprehensively summarizes recent advancements in understanding the regulatory roles of transcription factors in leaf senescence in important crops such as rice, wheat, maize, and soybean, and also briefly summarized significant findings in other crops such as sorghum, tomato, cotton, and cabbage. Additionally, we discuss molecular breeding strategies for optimizing crop performance through the manipulation of senescence by genetically engineering transcription factors. Schematic Illustrating Strategies and Key Considerations for Utilizing Senescence-Associated TFs in Crop Molecular Breeding. A) This panel illustrates the complex interplay between different TF families. For example, in tomato, changes in jasmonic acid (JA) hormone levels induced by darkness regulate SlMYC2 and SlVQ7 , which in turn influence the expression of SlWRKY37 and SlWRKY53 , highlighting the intricate network of interactions among TFs. B) This panel illustrates the functional conservation of homologous TFs. Although homologous TFs often exhibit functional conservation, it is important to note that functional divergence can also occur. C) This panel highlights the role of senescence-associated TFs in regulating nutrient remobilization during senescence. Specific TFs, such as OsNAC5 in rice and NAM in wheat, have been shown to control the accumulation and translocation of nutrients. D) This panel explores the potential of senescence-associated TF promoters in molecular breeding. By manipulating the expression of key TFs, it may be possible to delay or accelerate leaf senescence. E) This panel underscores the pleiotropic effects of senescence-associated TFs. For example, ZmNAC132 in maize not only regulates senescence but also influences male fertility, highlighting the need for careful consideration of potential unintended consequences. • Comprehensive review of TFs in leaf senescence regulation in major crops. • Focus on NAC and WRKY families as key regulators of leaf senescence. • Optimizing crop performance through TF manipulation for molecular breeding. • Identification of homologous TFs in different crops for molecular breeding.