Biodemography and senescence in long-lived painted turtles

长寿锦龟的生物人口学和衰老

• 批准号: 9272305
• 负责人: Anne Bronikowski
• 金额: $ 35.01万
• 依托单位: IOWA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-05-15 至 2020-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9272305
• 关键词: Address; Age; Aging; Animals; Archives; Biological Models; Biological Process; Cell physiology; Cessation of life; Clinical Research; Collection; Comparative Biology; Complex; DNA Library; Data; Databases; Demography; Deterioration; Drosophila genus; Ecology; Elderly; Environmental Impact; Evolution; Exhibits; Failure; Female; Fertility; Gene Expression; Gene Expression Regulation; Genes; Genetic; Genetic Models; Genome; Genotype; Geriatrics; Growth; Heritability; High-Throughput Nucleotide Sequencing; Human; Individual; Informatics; Inherited; Laboratories; Laboratory Study; Lead; Life; Life Experience; Light; Longevity; Longitudinal Studies; Mammals; Maps; Maternal Age; Measures; Mitochondria; Modeling; Molds; Molecular; Mus; Nematoda; Observational Study; Organ; Organism; Paint; Pattern; Phylogeny; Physiological; Population; Process; Quantitative Genetics; Regulation; Reporting; Reproduction; Reptiles; Research; Resources; Sampling; Series; Sex Characteristics; Social Impacts; Specificity; Stress; Study models; Techniques; Technology; Testing; Time; Tissue Banks; Turtles; Variant; Vertebrates; Work; age related; base; biodemography; cohort; experience; field study; flexibility; genetic analysis; genetic information; genetic pedigree; insight; life history; male; mortality; offspring; public health relevance; reproductive; reproductive senescence; resilience; senescence; sex; statistics; study population; theories; trait

DESCRIPTION (provided by applicant): Why do we senesce? This question has intrigued many, perhaps since the dawn of our species. Remarkably, recent work on turtles has detected no evidence of demographic senescence, i.e. - no mortality and reproductive aging. Theory predicts the circumstances under which aging should evolve, implying that such senescence may be evolutionarily labile and its occurrence context-dependent. While predictions from theory have been borne out in short-lived organisms under controlled conditions, our understanding of the ecology and evolution of senescence in long-lived organisms in the wild, where it evolved, is lacking. Moreover, evolutionarily conserved molecular networks underlie aging in a wide array of animal taxa (fruit flies, mice, nematode worms). Whether and how such genetic and cellular mechanisms underlie mortality and reproductive senescence outside of the realm of laboratory models remains unknown. Quantifying aging and the evolutionary, ecological, and physiological determinants of such senescence in exceptional taxa will yield valuable insights into the evolution and persistence of senescence, and its co-regulation with other life-history traits. We will investigate key aspects of the evolution, ecology and genetics of aging in a wild population of painted turtles (Chrysemys picta), which has been studied in detail since 1988. We will answer the following questions. 1) Do these C. picta exhibit age-related declines in reproduction and increases in mortality, which is evidence for senescence? 2) Are there differences between the sexes and are there long-lasting impacts of early- age experiences on late-life mortality and fertility trajectories? 3) Are sex differences and early-life impacts on aing rates context dependent? 4) Is offspring lifespan positively related to maternal age or maternal and paternal genotype, thereby suggesting the inheritance of lifespan? 5) Do age-specific physiological profiles (specifically, gene-expression and mitochondrial energetics) underlie mortality and reproduction trajectories similar to mammals and model genetic organisms? We will address these questions with coordinated experimental and analytical approaches. Existing informatics and collections-based resources accumulated over the past 24 yrs., including TurtleBase - a database comprising integrated ecological, environmental, evolutionary, and genetic information corresponding to hundreds of turtles and nests - will provide the input to an analytical pipeline for modeling the biodemography of aging. Importantly, our on-the-ground turtle population has individuals of known age ranging from hatchling to maximum lifespan (ca. 25 yrs.). Samples of these individuals combined with our archived tissue and DNA bank will be leveraged to render us uniquely able to test these important questions.

描述（由申请人提供）：我们为什么会衰老？这个问题引起了很多人的兴趣，也许从人类诞生之初就开始了。值得注意的是，最近对海龟的研究没有发现人口衰老的证据，即没有死亡率和生殖老化。理论预测了衰老应该进化的环境，这意味着这种衰老可能在进化上是不稳定的，它的发生取决于环境。虽然理论上的预测已经在受控条件下的短命生物中得到了证实，但我们对野外长寿生物衰老的生态学和进化的了解还很缺乏。此外，进化上保守的分子网络是许多动物类群（果蝇、老鼠、线虫）衰老的基础。这些遗传和细胞机制是否以及如何在实验室模型领域之外成为死亡和生殖衰老的基础仍然未知。量化衰老以及特殊类群中这种衰老的进化、生态和生理决定因素将对衰老的进化和持久性及其与其他生活史特征的共同调节产生有价值的见解。我们将研究自1988年以来对野生彩龟种群（Chrysemys picta）进行详细研究的进化、生态学和衰老遗传学的关键方面。我们将回答以下问题。1)这些C. picta是否表现出与年龄相关的繁殖能力下降和死亡率上升，这是衰老的证据？2)两性之间是否存在差异？早期经历对晚年死亡率和生育轨迹是否存在长期影响？3)性别差异和早期生活对死亡率的影响是否依赖于环境？4)后代寿命是否与母亲年龄或父母基因型呈正相关，从而提示寿命遗传？5)年龄特异性生理特征（特别是基因表达和线粒体能量学）是否构成与哺乳动物和模式遗传生物相似的死亡率和繁殖轨迹的基础？我们将用协调的实验和分析方法来解决这些问题。现有的信息学和馆藏资源是过去24年积累起来的。，包括TurtleBase——一个包含上百只海龟和巢的综合生态、环境、进化和遗传信息的数据库——将为建立老龄化生物人口统计学模型的分析管道提供输入。重要的是，我们的地面海龟种群有已知年龄的个体，从孵化到最大寿命（约25年）。这些人的样本与我们存档的组织和DNA库相结合，将使我们能够独特地测试这些重要的问题。