An energy-sensitive pathway of cold-induced metabolic remodeling in threespine stickleback

三刺刺鱼冷诱导代谢重塑的能量敏感途径

• 批准号: 1756191
• 负责人: Kristin O'Brien
• 金额: $ 68.96万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1756191&HistoricalAwards=false
• 关键词: energy; sensitive; pathway; cold; induced

Adjustments in metabolism are necessary to meet changing energetic demands that result from processes such as exercise, temperature fluctuations, and diseases such as cancer. One of the most striking examples of alterations in metabolism occurs in fish in response to temperature. Because fish are ectotherms, with body temperatures equivalent to their environment, some species may experience body temperature changes as great as 15-20oC diurnally or seasonally, requiring adjustments in metabolism to maintain activity and swimming performance. Although metabolic remodeling in response to temperature has been well documented in several fish species, little is known about how it is regulated. While some components of the regulatory pathway are similar between fish and mammals, others differ, providing an opportunity to expand understanding of how metabolism is regulated. This project will identify the signaling pathway involved in temperature-induced changes in metabolism in the threespine stickleback fish. Stickleback are ideal for these studies because they inhabit thermally variable environments and their genome has been sequenced, making molecular biological studies more tractable compared to other species. High-school, undergraduate, and graduate students will participate in this research, obtaining training in physiology, biochemistry, and molecular biology. Native Alaskan high school students will be involved through independent studies as part of the Rural Alaskan High School Honors Institute, a six-week college preparatory program at the University of Alaska, Fairbanks. Results from this research will provide a better understanding of how metabolism is regulated, a process essential to the health of all organisms.This project investigates mechanisms of phenotypic plasticity, specifically the role of sirtuins, NAD+-dependent deacetylases, in driving metabolic reorganization in response to temperature in the threespine stickleback, Gasterosteus aculeatus. The hypothesis will be tested that sirtuins activate c-MYC, a potent regulator of cell growth and metabolism, and that differences in chromatin packing among different tissues will affect c-MYC binding, resulting in tissue-specific metabolic remodeling that is reflected in the degree of thermal compensation at the organismal level in aerobic metabolic scope. Stickleback will be acclimated to three temperatures (5, 12, or 20oC) for 10 weeks. Maximal activities of key metabolic enzymes, mitochondrial respiration rates in permeabilized cells, aerobic metabolic scope, and levels of adenylates, sirtuins, and c-MYC will be quantified in liver and glycolytic and oxidative muscles. Levels of sirtuins will then be manipulated in vivo in animals at 12oC and these parameters quantified, along with the expression of select mitochondrial genes. Gene targets of c-MYC will be identified using chromatin immunoprecipitation coupled with high throughput sequencing (ChIP-Seq), and a c-MYC promoter and reporter construct will be used to assess c-MYC DNA binding activity in vivo during thermal acclimation. This project will determine how changes in metabolism at the cellular level contribute to whole-organismal metabolic remodeling and identify components of the signaling cascade driving tissue-specific metabolic remodeling, creating an integrated understanding of metabolic remodeling that spans molecular, cellular and organismal levels. Broader impacts include graduate student training and research opportunities for Native Alaskan high-school students participating in a six-week summer college preparatory program.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.

新陈代谢的调整是必要的，以满足不断变化的能量需求，这些需求来自运动，温度波动和癌症等疾病。鱼类对温度的反应是新陈代谢发生变化的最显著的例子之一。由于鱼类是外温动物，其体温与环境相当，一些物种可能会经历昼夜或季节性的体温变化高达15- 20摄氏度，需要调整新陈代谢以保持活动和游泳能力。虽然在几种鱼类中已经有很好的记录了对温度的代谢重塑，但对它是如何调节的知之甚少。虽然鱼类和哺乳动物之间的调节途径的某些组成部分是相似的，但其他组成部分不同，这为扩大对代谢如何调节的理解提供了机会。本研究将探讨温度对三棘鱼代谢影响的信号通路。刺鱼是这些研究的理想选择，因为它们栖息在温度可变的环境中，它们的基因组已经被测序，这使得分子生物学研究比其他物种更容易处理。高中生、本科生和研究生将参与这项研究，获得生理学、生物化学和分子生物学方面的培训。阿拉斯加本地高中学生将通过独立学习参与阿拉斯加农村高中荣誉研究所的一部分，这是阿拉斯加大学费尔班克斯为期六周的大学预科项目。从这项研究的结果将提供一个更好地了解如何代谢的调节，一个过程中必不可少的健康的所有organis.This项目调查表型可塑性的机制，特别是sirtuins，NAD+依赖的脱乙酰酶，在驱动代谢重组的反应温度在threespine棘鱼，Gasterosteus aculeatus的作用。将检验以下假设：sirtuins激活c-MYC（细胞生长和代谢的有效调节剂），并且不同组织中染色质包装的差异将影响c-MYC结合，导致组织特异性代谢重塑，其反映在有氧代谢范围内生物体水平的热补偿程度中。刺鱼将适应三种温度（5、12或20摄氏度）10周。将在肝脏和糖酵解和氧化肌肉中定量关键代谢酶的最大活性、透化细胞中的线粒体呼吸速率、有氧代谢范围以及腺苷酸、沉默调节蛋白和c-MYC水平。然后在12 ℃下在动物体内操纵沉默调节蛋白的水平，并对这些参数进行量化，同时沿着选择线粒体基因的表达。将使用染色质免疫沉淀结合高通量测序（ChIP-Seq）鉴定c-MYC的基因靶标，并使用c-MYC启动子和报告基因构建体评估热适应期间的体内c-MYC DNA结合活性。该项目将确定细胞水平的代谢变化如何促进整个生物体的代谢重塑，并确定驱动组织特异性代谢重塑的信号级联的组成部分，从而对跨越分子，细胞和生物体水平的代谢重塑产生综合理解。更广泛的影响包括研究生培训和研究机会，为阿拉斯加原住民高中学生参加为期六周的夏季大学预科课程。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

项目成果

Metabolic rate increases with acclimation temperature and is associated with mitochondrial function in some tissues of threespine stickleback

代谢率随着驯化温度的增加而增加，并且与三刺鱼某些组织中的线粒体功能相关

• DOI: 10.1242/jeb.244659
• 发表时间: 2022
• 期刊: Journal of Experimental Biology
• 影响因子: 2.8
• 作者: Cominassi, Louise;Ressel, Kirsten N.;Brooking, Allison A.;Marbacher, Patrick;Ransdell-Green, Eleanor C.;O'Brien, Kristin M.
• 通讯作者: O'Brien, Kristin M.