Sequestration and clearance of age-induced damage in gametogenesis

配子发生过程中年龄诱导损伤的隔离和清除

• 批准号: 9757589
• 负责人: Jay S Goodman
• 金额: $ 4.03万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-20 至 2021-07-19
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9757589
• 关键词: Address; Affect; Age; Aging; Animal Model; Apoptosis; Autophagocytosis; Biological Models; Caenorhabditis elegans; Candidate Disease Gene; Cell Aging; Cell Nucleolus; Cell Nucleus; Cell division; Cells; Chemicals; Complex; Coupled; Cytolysis; Cytoplasm; DNA; Data; Diploidy; Disease; Exclusion; Exhibits; Fluorescence; Functional disorder; Gametogenesis; Generations; Genes; Genetic; Genetic Recombination; Germ Cells; Haploidy; Inherited; Lead; Left; Longevity; Lysosomes; Mediating; Meiosis; Membrane Proteins; Microfluidics; Microscopic; Mitotic; Modeling; Molecular; Mothers; Mutation; Natural regeneration; Nature; Nuclear; Nuclear Envelope; Nuclear Pore; Nuclear Pore Complex; Nuclear Pore Complex Proteins; Nutrient; Organelles; Organism; Pathway interactions; Peptide Hydrolases; Process; Protease Inhibitor; Proteins; Quality Control; Refractory; Rejuvenation; Reporting; Reproduction spores; Research; Ribosomal DNA; Saccharomyces cerevisiae; Saccharomycetales; Site; Stem cells; System; Testing; Therapeutic; Ubiquitin; Vacuole; Yeasts; age related; aged; cell age; combat; daughter cell; experimental study; genetic approach; genetic manipulation; genetic pedigree; healthspan; improved; knock-down; live cell imaging; live cell microscopy; multicatalytic endopeptidase complex; mutant; precursor cell; programs; protein aggregate; protein aggregation; proteotoxicity; trait; yeast genetics

Organisms acquire damage as they age1, 2. Common traits that are associated in aged cells are the accumulation of protein aggregates, nucleolar abnormalities and dysfunctional organelles2, 3,5. However, it remains difficult to distinguish which traits directly promote cellular aging, versus those that arise as a consequence of aging. Generating a model system that addresses this issue will allow us to develop better therapeutic strategies to combat aging and improve health span. Similar to metazoans, budding yeast accumulates protein aggregates, nucleolar abnormalities and dysfunctional organelles during aging. Surprisingly, as aged yeast cells undergo gametogenesis, the resulting gametes no longer contain the age-associated traits6. Furthermore, the longevity of the gametes is restored by this process, suggesting that elimination of age-associated traits causes cellular rejuvenation6. I aim to dissect the molecular mechanisms that counteract age-induced damage during gametogenesis and test their impact on lifespan. The experiments in Aim 1 will determine which genes in budding yeast cause gametes to avoid the inheritance of age-associated traits. Analyses so far indicate that cellular contents subject to age-induced damage, including nuclear pore complexes, protein aggregates and the nucleoli, localize to a subcompartment of the nuclear envelope during gametogenesis. This compartment is not inherited by the gametes as they regenerate contents de novo 8, 12. These observations suggest that age-induced traits are associated with the nuclear envelope subcompartment via specific adaptors, which cause their exclusion from the gametes. If true, disruption of each candidate adaptor should lead to retention of a distinct type of age-induced damage. In parallel, an unbiased genetic approach will be taken to screen for mutants that pass on age-induced traits to their gametes30. Further assessment of each mutant by microfluidic pedigree analyses will reveal which traits are limiting for lifespan39. The experiments in Aim 2 will determine how long-lived proteins that accumulate in aged cells are destroyed during budding yeast and C.elegans gametogenesis. Budding yeast gametes do not inherit the vacuole of the progenitor cell, which is ultimately destroyed. When the vacuole lyses, it releases proteases that normally degrade long-lived proteins7, 13, 14. Therefore, inhibiting vacuolar proteases, as well as other factors associated with protein quality control may cause long-lived proteins found in aged cells to persist during gametogenesis. Similar phenomena have been recently reported in the C.elegans germline, which will additionally be explored17, 18. The results will be verified by yeast genetics, worm genetics and fluorescence live-cell imaging. Identifying the genes required to eliminate long-lived proteins will facilitate the generation of new strategies to remove proteotoxic damage.

生物在年龄1、2中获得损害。与老年细胞相关的常见特征是 蛋白质聚集体，核仁异常和功能障碍细胞器的积累2，3,5。但是，它 仍然很难区分哪些特征直接促进细胞衰老，而不是作为 衰老的结果。生成一个解决此问题的模型系统将使我们能够更好地发展 对抗衰老和改善健康跨度的治疗策略。 与后生动物相似，萌芽的酵母累积了蛋白质聚集体，核仁异常和 衰老过程中功能失调的细胞器。令人惊讶的是，随着老化的酵母细胞经历配子发生，由此产生的 配子不再包含与年龄相关的特征6。此外，配子的寿命还恢复了 这一过程表明消除与年龄相关的特征会导致细胞恢复6。我的目标是剖析 抵消在配子发生过程中对年龄引起的损害并测试其影响的分子机制 在寿命上。 AIM 1中的实验将确定萌芽酵母中哪些基因引起配子以避免 与年龄相关性状的继承。到目前为止的分析表明，受年龄诱导的细胞含量 损坏，包括核孔复合物，蛋白质聚集体和核仁，本地化 在配子发生过程中的核包膜。这个隔室不是配子所继承的 再生目录从头8、12。这些观察结果表明，年龄引起的特征与 通过特定适配器的核包膜子组门，这会导致它们排除在配子之外。如果是真的， 每个候选适配器的破坏应导致保留不同年龄诱导的损害。在 并行，将采用一种公正的遗传方法来筛选以年龄诱导的特征为止的突变体 他们的配子30。通过微流体谱系分析对每个突变体的进一步评估将揭示哪些特征 限制了寿命39。 AIM 2中的实验将确定在老化细胞中积聚的长寿命蛋白是 在萌芽的酵母和C.元素配子发生过程中被破坏。发芽的酵母配子不继承 祖细胞的液泡，最终被破坏。当液泡裂解时，它会释放出蛋白酶 通常降解长寿命蛋白7、13、14。因此，抑制液泡蛋白酶以及其他因素 与蛋白质质量控​​制相关的可能会导致在老年细胞中发现的长寿命蛋白质在 配子发生。最近在C.Elegans种系中报道了类似现象，这将 另外可以探索17，18。结果将通过酵母遗传学，蠕虫遗传学和荧光来验证 活细胞成像。确定消除长寿命蛋白所需的基因将有助于产生 消除蛋白毒性损伤的新策略。