Collaborative Research: RUI: Extraordinary circadian clocks in araneoid spiders: an integrative approach to understanding their evolutionary origins and underlying mechanisms

合作研究：RUI：类蜘蛛的非凡生物钟：一种理解其进化起源和潜在机制的综合方法

• 批准号: 2235710
• 负责人: Darrell Moore
• 金额: $ 40.36万
• 依托单位: East Tennessee State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2026-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2235710&HistoricalAwards=false
• 关键词: Collaborative; Research; RUI; Extraordinary; circadian

Circadian rhythms are daily rhythms of behavior, physiology, and cellular metabolism that are driven by molecular cycles of an internal biological clock. Internal clocks remain in sync with the earth’s 24-h day by making small adjustments to their own internal clock period. However, there are negative physiological consequences if the clock is forced to make large adjustments (e.g., jetlag) so most organisms’ clocks do not vary much from 24 hours. Surprisingly, a group of spider species possess clocks that differ from 24 hours by as much as 5 hours with no apparent consequences. In theory, these species should not exist. However, the spider system provides a unique opportunity to explore basic mechanisms of circadian clocks, particularly how organisms synchronize with their environment. This multi-institutional project is designed to understand: (1) the evolutionary changes in clock genes and circadian properties in spiders, (2) the limits and physiological consequences of synchronizing to the 24-h day, and (3) the fundamental molecular clockworks of spiders. Overall, this project will develop a new, and uniquely powerful, model system to understand circadian rhythms and, potentially, circadian illnesses. Circadian rhythms are conceptually accessible to students and this project will support rich opportunities for undergraduates in the Appalachian region to participate in research at all three institutions. Societal impacts of this project will include development of user-friendly, open-access applications for rigorous analyses of circadian data, annual public outreach events including nature/STEM programs for K-12 students as well as adults, and conducting original experiments in local high schools. Araneoid spider circadian rhythms are unlike most others found on Earth. They exhibit remarkably broad distributions of endogenous free-running periods (FRPs) both within and among species, including species with exceptionally short or long mean FRPs (17.8-29.1 hours). Rather than suffering negative consequences typically associated with dissonance between endogenous circadian period and the 24-hour day, survivorship experiments suggest that these spiders are somehow released from these selective constraints. Using an integrative, multi-level approach, this project will exploit the apparent evolutionary shift in circadian clock system function between araneoid and non-araneoid spider species to identify changes in the clock mechanisms that enable these unusual araneoid clocks to exist. Using genomic or transcriptomic-scale data to estimate rates of evolutionary change in eight different chronobiological parameters for species spanning the diversity of spiders will enable reconstruction of ancestral states and pinpoint the timing of evolutionary shifts. Comparing survivorship among araneoid and non-araneoid species will determine if araneoid spiders truly have been released from the costs of entrainment to non-resonant light/dark cycles. Classic phase-shifting and phase-response curve experiments will probe differences in entrainment potential between araneoid and non-araneoid spiders. Comparing canonical clock gene expression amplitudes between araneoid and non-araneoid spiders and to established insect models will explore potential clock function differences. Comparing the functionality of the clock component CRY1 between araneoid and non-araneoid species will test for differences in light sensitivity of the circadian system. Using molecular, behavioral, and phylogenetic approaches, this project explores the extent and functional ramifications of circadian plasticity in wild clocks.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.

昼夜节律是由内部生物时钟的分子循环驱动的行为，生理和细胞代谢的每日节奏。内部时钟通过对自己的内部时钟周期进行少量调整，与地球的24-H天保持同步。但是，如果时钟被迫进行大量调整（例如，喷射lag），则会产生负面的后果，因此大多数生物的时钟与24小时的变化不大。出人意料的是，一组蜘蛛种具有与24小时不同的时钟不同，高达5小时，没有明显的后果。从理论上讲，这些物种不应该存在。但是，蜘蛛系统为探索昼夜节律时钟的基本机制提供了独特的机会，尤其是生物体与环境同步的方式。这个多机构的项目旨在理解：（1）蜘蛛中时钟基因和昼夜节律性质的进化变化，（2）同步到24小时的限制和物理后果，以及（3）蜘蛛的基本分子发条。总体而言，该项目将开发出一种新的且独特的模型系统，以了解昼夜节律以及昼夜节律。学生在概念上可以访问昼夜节律，该项目将为阿巴拉契亚地区的本科生提供丰富的机会参加所有三个机构的研究。该项目的社会影响将包括开发对用户友好的开放式申请应用程序，以严格分析昼夜节目数据，年度公共外展活动，包括针对K-12学生和成人的自然/STEM计划，以及在当地高中进行原始实验。 Araneoid Spider昼夜节律与地球上大多数其他发现不同。他们暴露了内源性自由运行时期（FRP）内部和物种之间的广泛分布，包括具有非常短或长的FRP（17.8-29.1小时）的物种。生存实验并没有遭受负面后果，通常与内源性昼夜节律之间的不和谐相关，而是表明这些蜘蛛是从这些选择性约束中释放出来的。使用综合性的多层次方法，该项目将利用昼夜节和非氨基蜘蛛物种之间昼夜节律时钟系统功能的明显进化变化，以识别使这些异常的无形钟表存在的时钟机制的变化。使用基因组或转录组尺度数据来估计跨越蜘蛛多样性物种的八种不同的年度生物学参数的进化变化速率，将实现祖先状态的重建并确定进化转移的时间。比较Araneoid和非氨基类物种之间的生存将确定是否真正从非共鸣光/暗循环的入口成本中释放出了Araneoid Spider。经典的相位移动和相响应曲线实验将探测Araneoid和非氨基蜘蛛之间入口电位的差异。比较摩soid和非氨基蜘蛛之间的规范时钟基因表达放大器以及已建立的绝缘模型将探索潜在的时钟功能差异。比较弧形和非氨基化物种之间的时钟组分CRY1的功能将测试昼夜节律系统光灵敏度的差异。该项目使用分子，行为和系统发育方法，探讨了野生时钟中昼夜节律可塑性的程度和功能后果。该奖项反映了NSF的法定任务，并被认为是通过基金会的智力优点和更广泛的影响来通过评估来获得的支持。