CAREER: Understanding non-photochemical quenching under chilling in the warm-season C4 grasses

该奖项的全部或部分资金来自《2021年美国救援计划法案》(公法117-2)。对低温的敏感性极大地限制了作物的分布、建立和生产力。重要的经济牧草，如玉米和甘蔗，起源于温暖的气候，没有形成抵御寒冷的能力。在低温下，叶片吸收的太阳能大大超过了二氧化碳固定的使用量，这会导致氧化胁迫和随后的光损伤，停止生长，最终导致植物死亡。作为一种光保护反应，树叶会切换到安全模式，在这种模式下，多余的能量可以无害地释放出来。对于温暖气候的牧草在寒冷条件下的这些保护性开关，人们知之甚少。因此，本项目综合了生理学、生化、遗传学、代谢组学和田间表现学等多学科的研究成果，旨在揭示植物在低温和低温条件下对氧化应激的保护机制。提高温暖气候作物的耐冷性将增加它们的气候适应能力，使春季种植/再生更早，从而延长生长季，同时促进增加对早期季节土壤水分的利用。教育部分将对本科生进行终身科学交流技能的培训。研究经验将为女本科生和研究生以及博士后提供工具性培训。妇女更多地参与科学、技术和经济研究，将造就一支更多样化、更强大的科学队伍。公众推广活动将旨在提高人们对养育世界的研究创新的接受度和鉴赏度。这项提议的研究目的是了解C4暖季牧草在低温下的非光化学猝灭(NPQ)机制。这项研究将在芒属植物上进行，芒属植物是玉米和甘蔗的近亲，同时也非常耐低温。芒属植物广泛的地理分布为阐明C4光合作用耐冷性的潜在机制提供了独特的机会。通过跨越生物组织水平，该项目将1)确定NPQ的冷依赖特性及其对植物生理的影响；2)确定NPQ相关的关键基因如何对NPQ特性的冷光依赖和非独立变化做出贡献；3)确定NPQ如何在整个生物体水平上整合。以下教育目标与研究相结合：4)开发和传播本科水平的课程，以提高学生的科学交流技能；5)通过实践活动让女孩参与植物科学；以及6)教育和参与公众关于光合作用及其在作物物种上的潜在改良。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).Sensitivity to low temperatures greatly limits the distribution, establishment, and productivity of crops. The economically important grasses such as maize and sugarcane originated in a warm climate and did not develop protection against cold. In low temperatures, solar energy absorbed by leaves exceeds greatly its use for CO2 fixation, which leads to oxidative stress and subsequent photodamage, arrest of growth and eventually plant death. As a photoprotective response, the leaf switches into a ‘safety mode’ where an excess of energy can be harmlessly released. Little is known about these protective switches in warm climate grasses under cold conditions. Therefore, this project integrates physiology, biochemistry, genetics, metabolomics and field phenomics to reveal the regulation of protective mechanisms against oxidative stress under chilling and cold. Improved chilling tolerance of warm climate crops would increase their climate resilience, enable an earlier spring planting/regrowth that would extend the growing season while facilitating increased use of early season soil-moisture. The education component will train undergraduate students on the life-long skill of science communication. The research experiences will provide instrumental training to female undergraduate and graduate students, and a postdoctoral fellow. Increased participation of women in STEM will lead to a more diverse and stronger scientific workforce. The public outreach activities will aim for higher acceptance and appreciation for research innovation in feeding the world.The research goal of this proposal is to understand the non-photochemical quenching (NPQ) mechanism under chilling in C4 warm-season grasses. The study will be performed on Miscanthus, which is a close relative to maize and sugarcane while being also extremely tolerant to low temperatures. The extensive geographical distribution of Miscanthus offers unique opportunities to elucidate the underlying mechanisms of C4 photosynthesis tolerance to chilling. By spanning across levels of biological organization this project will 1) Define chilling-dependent characteristics of NPQ and their effect on plant physiology; 2) Identify how key NPQ related genes contribute to chilling light-dependent and -independent changes in NPQ characteristics; 3) Determine how NPQ is integrated at the level of the whole organism. The following education objectives are integrated with the research: 4) Develop and disseminate an undergraduate-level course to increase students’ science communication skills; 5) Engage girls in plant science via hands-on activities; and 6) Educate and engage the public on photosynthesis and its potential improvement in crop species.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.