A new invertebrate model for the mitochondrial basis of aging

项目摘要 线粒体曾经被简单地认为是产生ATP的细胞器，但现在已知 通过对核转录的无数影响来影响衰老和与年龄有关的疾病， 翻译.病原性线粒体DNA（mtDNA）的母体传播可能是 通过线粒体替代疗法预防。然而，这种治疗方法有诱发线粒体损伤的风险。 冲突，其影响可能不会变得明显，直到晚年的生活，可能会有所不同， 性别拟议的项目将开发甲壳类动物Tigriopus californicus作为新的模式 线粒体和线粒体相互作用对性别特异性衰老的影响，包括 死亡率、mtDNA含量、氧化应激和基因表达的测定。该物种 特别适合于实验工作，在实验室中很容易提高，寿命短 循环，适合于多代控制杂交，并具有丰富的基因组 资源（包括多个种群的全基因组和转录组）。此外，它是一个 理解线粒体相互作用的新兴模型，部分原因是可行的和肥沃的 杂交种很容易在具有巨大差异的种群之间产生， 线粒体DNA该系统还具有性别特异性线粒体效应不会被破坏的优点。 由于该物种没有性别， 染色体（相反，性别决定是多基因的）。本研究将集中在倒数F1 两个种群之间的杂交，mtDNA差异约为19%，具有实质性差异 在所有37个基因座中，包括所有13个蛋白质编码基因座的非同义变化。复制 将测定亲本和正反交F1系的性别特异性死亡率、寿命 线粒体DNA含量和缺失率、氧化应激（8-OH-的ELISA定量）、 dG）和基因表达（RNAseq）。加权基因共表达分析（WGCNA）将在 用于识别与细胞核共享共表达网络的核基因模块， 编码基因，并将模块与衰老表型相关。这一新模式的发展 系统将拓宽我们对衰老的线粒体基础的理解，并将提供一个 这是一个前所未有的机会，可以评估整个线粒体基因组突变的影响。

Project Summary Mitochondria were once simply considered organelles that generate ATP but are now known to impact aging and age-related diseases through their myriad effects on nuclear transcription and translation. Maternal transmission of pathogenic mitochondrial DNA (mtDNA) could be prevented by mitochondrial replacement therapy. This cure, however, risks inducing mitonuclear conflicts, whose effects may not become apparent until late in life and may differ between the sexes. The proposed project will develop the crustacean Tigriopus californicus as a new model for the effect of mitochondria and mitonuclear interactions on sex-specific aging, including assays of mortality rate, mtDNA content, oxidative stress and gene expression. The species is particularly suited for experimental work in that is easily raised in the laboratory, has a short life cycle, is amenable to multiple generations of controlled crosses and has abundant genomic resources (including full genomes and transcriptomes for multiple populations). Further, it is an emerging model for understanding mitonuclear interactions, in part because viable and fertile hybrids are easily produced in crosses between populations with tremendously divergent mtDNA. The system also has the advantage that sex-specific mitochondrial effects will not be confounded by the presence of sex chromosomes, because the species does not have sex chromosomes (instead, sex determination is polygenic). This study will focus on reciprocal F1 crosses between two populations at ~19% mtDNA divergence, with substantial differences across all 37 loci, including non-synonymous changes for all 13 protein coding loci. Replicated parental and reciprocal F1 lines will be assayed for sex-specific mortality rate, lifespan, mitochondrial DNA content and deletion ratio, oxidative stress (ELISA quantification of 8-OH- dG) and gene expression (RNAseq). Weighted gene co-expression analysis (WGCNA) will be used to identify nuclear gene modules that share co-expression networks with mitochondrially- encoded genes, and to relate modules to aging phenotypes. Development of this new model system will broaden our understanding of the mitochondrial basis of aging, and will provide an unprecedented opportunity to assess effects of mutations throughout the mitochondrial genome.