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？也许从我们人类诞生之日起，这个问题就引起了许多人的兴趣。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，即没有死亡和生殖衰老。理论预测了衰老应该在什么情况下进化，这意味着这种衰老可能在进化上不稳定，并且其发生依赖于环境。虽然理论预测已在受控条件下的短寿命生物体中得到证实，但我们对野生长寿生物体（其进化地）的衰老的生态和进化仍缺乏了解。此外，进化上保守的分子网络是多种动物类群（果蝇、小鼠、线虫）衰老的基础。在实验室模型领域之外，这种遗传和细胞机制是否以及如何导致死亡和生殖衰老仍然未知。量化特殊类群中的衰老以及这种衰老的进化、生态和生理决定因素，将为了解衰老的进化和持久性及其与其他生活史特征的共同调节提供有价值的见解。 我们将调查野生锦龟 (Chrysemys picta) 种群的进化、生态学和衰老遗传学的关键方面，自 1988 年以来对此进行了详细研究。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增加，这是衰老的证据？ 2）性别之间是否存在差异？早年经历对晚年死亡率和生育轨迹是否有长期影响？ 3) 性别差异和早年对死亡率的影响是否取决于环境？ 4）后代寿命是否与母亲年龄或母本基因型呈正相关，从而暗示寿命的遗传？ 5）特定年龄的生理特征（特别是基因表达和线粒体能量学）是否是与哺乳动物和模型遗传生物类似的死亡率和繁殖轨迹的基础？ 我们将通过协调的实验和分析方法来解决这些问题。过去 24 年积累的现有信息学和基于馆藏的资源，包括 TurtleBase（一个数据库，包含与数百只海龟和巢穴相对应的综合生态、环境、进化和遗传信息），将为分析管道提供输入，用于对海龟进行建模。衰老的生物人口学。重要的是，我们的陆龟种群中的已知年龄范围从刚孵化的海龟到最长寿命（约 25 岁）。这些个体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问题。