Collaborative Research: Insults for free: the roles of metamorphosis and dormancy in aging dynamics

生理年龄并不总是与实足年龄相关，生理如何导致衰老或防止衰老也不清楚。一些假说预测生物体会修复繁殖所必需的组织，同时允许其他组织老化。其他假说则相反：与生殖有关的组织会因为早期生命适应性的选择而衰老得更快。这项研究将研究生命阶段和组织的衰老动态，以及对压力的反应。蜜蜂是一个理想的系统，可以用来探索寿命极端差异的机制基础，从而对衰老的调节机制有一个大致的了解。与脊椎动物相比，蜜蜂的生命周期较短，因此有可能研究衰老的一生模式。而且，细胞衰老的许多方面在昆虫和脊椎动物中都是保守的。研究不同物种之间的衰老动力学差异可能会导致破坏衰老负面影响的新方法。在一个生物越来越多地暴露于压力和许多蜜蜂物种正在减少的世界里，理解衰老是特别紧迫的。建议的研究将支持培养六名研究生和六名本科生。将开发一个关于大黄蜂春季出现的K-12学习模块，作为让美国原住民高中生参与STEM的实践课程。作为正在进行的合作的一部分，将与红河谷动物园（法戈，ND）和科学儿童和怀俄明州PBS（拉勒米，WY）一起开发有关传粉媒介的信息展览和外展活动。提出的研究目的是将生理学与生活史理论结合起来，以机械的方式解释衰老的模式。昆虫变态可能是一次性躯体假说的一个极端版本。在变态过程中，幼虫组织被循环利用，并被具有干细胞样特性的想象细胞所取代，这些细胞有可能比它们所取代的组织更“年轻”。昆虫的变态可能提供了一个处理受损体细胞组织的机会，减轻了幼年暴露于压力的影响。昆虫的越冬，也被称为滞育，对衰老也有重要的影响。与非滞育个体相比，滞育延长了六倍的寿命。本研究将通过检查细胞损伤和机体性能，确定变态和滞育如何促进衰老动力学：1)确定衰老与衰老细胞标志物之间的关系；2)通过比较蜕变过程中形成的组织与幼虫期遗留下来的组织中的细胞衰老，研究蜕变过程中的一次性体细胞如何影响衰老；3)评估越冬休眠是减缓衰老还是再生。拟议的研究将调查独居蜜蜂和大黄蜂的这些动态，并将加强NDSU， UW和USDA-ARS之间已经富有成效的合作，并极大地扩展对导致衰老变化的机制的了解。该项目由综合生态生理学项目和促进竞争研究的既定项目（EPSCoR）共同资助。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Biological age does not always correlate with chronological age, and it is unclear how physiology contributes to aging or protects from it. Some hypotheses predict that organisms will repair tissues necessary for reproduction, while allowing other tissues to age. Other hypotheses predict the opposite: tissues related to reproduction will age faster because of selection for early life fitness. This research will examine aging dynamics across life stages and tissues, and in response to stress. Bees are an ideal system to probe the mechanistic underpinnings of extreme differences in lifespan, yielding general insight into regulators of aging. Bee life-cycles are short compared to vertebrates and its possible to examine lifetime patterns of senescence. And, many aspects of cellular senescence are conserved across insects and vertebrates. Investigating how aging dynamics differ among species may lead to new ways of disrupting negative effects of aging. Understanding aging is particularly pressing in a world in which organisms are increasingly exposed to stress and many bee species are in decline. The proposed research will support the training of six graduate students and six undergraduate students. A K-12 learning module on bumble bee spring emergence will be developed as a hands-on lesson to engage Native American high school students in STEM. As part of an ongoing collaboration, informational exhibits and outreach events about pollinators will be developed with the Red River Valley Zoo (Fargo, ND) and Science Kids and Wyoming PBS (Laramie, WY). The objective of the proposed research is to integrate physiology with life history theory to mechanistically explain patterns of aging. Insect metamorphosis may be an extreme version of the disposable soma hypothesis. During metamorphosis, larval tissues are recycled and replaced by imaginal cells with stem cell-like properties, which have the potential to be cellularly “younger” than the tissues they replace. Insect metamorphosis may provide an opportunity to dispose of damaged somatic tissues, mitigating the effects of juvenile exposure to stress. Insect overwintering, also known as diapause, also has important implications for aging. Diapause increases lifespans by six times compared to non-diapausing individuals. This research will determine how metamorphosis and diapause contribute to aging dynamics by examining cellular damage and organismal performance by: 1) determining the relationship between senescence and cellular markers of aging, 2) examining how the disposable soma during metamorphosis influences aging by comparing cellular aging in tissues formed during metamorphosis to those carried over from the larval stage, and 3) assessing whether overwintering dormancy is a slowing down of aging or is regenerative. The proposed research will investigate these dynamics in solitary bees and bumble bees, and will strengthen an already productive collaboration between NDSU, UW, and the USDA-ARS, and greatly extend what is known about the mechanisms that contribute to variation in senescence.This project is jointly funded by the Integrative Ecological Physiology program and the Established Program to Stimulate Competitive Research (EPSCoR).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.