GIGANTEA adjusts the response to shade at dusk by directly impinging on PHYTOCHROME INTERACTING FACTOR 7 function

• 成果类型: Article
• 署名作者: Martinez-Vasallo, Carlos; Cole, Benjamin; Perez-Alemany, Jaime; Ortiz-Ramirez, Clara I.; Gallego-Bartolome, Javier; Chory, Joanne; Kay, Steve A.; Nohales, Maria A.
• 署名单位: Consejo Superior de Investigaciones Cientificas (CSIC); Universitat Politecnica de Valencia; CSIC-UPV - Instituto de Biologia Molecular y Celular de Plantas (IBMCP); University of Southern California; Salk Institute; Howard Hughes Medical Institute; United States Department of Energy (DOE); Joint Genome Institute - JGI; Lawrence Berkeley National Laboratory
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-13685
• DOI: 10.1073/pnas.2315778121
• 发表日期: 2024-07-23
• 关键词: circadian clock; plant-growth; red-light; avoidance responses; hypocotyl growth; factor pif7; arabidopsis; auxin; DYNAMICS; protein

摘要

For plants adapted to bright light, a decrease in the amount of light received can be detrimental to their growth and survival. Consequently, in response to shade from surrounding vegetation, they initiate a suite of molecular and morphological changes known as the shade avoidance response through which stems and petioles elongate in search for light. Under sunlight-night cycles, the plant's responsiveness to shade varies across the day, being maximal at dusk time. While a role for the circadian clock in this regulation has long been proposed, mechanistic understanding of how it is achieved is incomplete. Here, we show that the clock component GIGANTEA (GI) directly interacts with the key player in the response to shade. GI represses PIF7 transcriptional activity and the expression of its target genes in response to shade, thereby fine- tuning the magnitude of the response to limiting light conditions. We find that under light/dark cycles, this dusk. Importantly, we also show that this circuit primarily operates in epidermal cells, highlighting the relevance of tissue- specific clock- output connections for the regulation of plant development in resonance with the environment.