Aging specific gene expression in Drosophila

描述（由申请人提供）：本研究的长期目标是利用模式生物黑腹果蝇了解衰老过程中基因表达的调控。研究发现，果蝇和人类的衰老与氧化应激反应基因的组织特异性诱导有关，包括hsp 70家族和hsp 22（α-晶状体蛋白）家族的成员。热休克蛋白（hsps）在所有物种中诱导响应热和其他压力。HSPs似乎参与蛋白质损伤的预防和修复，并可赋予许多细胞类型增加的热和氧化应激抗性。果蝇hsp 70和hsp 22基因在衰老过程中以特征性的组织特异性模式被诱导。这种与衰老相关的上调涉及转录和转录后机制，似乎部分是对氧化应激的反应。hsp 22表现出已知的真核蛋白质的最大的老化相关增加（>150倍）。hsp 70和hsp 22的同源物在人类正常衰老期间以及在许多病理生理学和衰老相关疾病状态中上调。我们假设热休克蛋白基因表达的改变是一种普遍的衰老生物标志物，是正常的核-线粒体信号转导的破坏的结果。我们拟详细研究果蝇hsp 70和hsp 22的衰老相关转录调控。该研究涉及果蝇基因表达和寿命的遗传和转基因操作。这些实验将检验几个与衰老和热休克蛋白基因表达有关的特定假设。细胞的代谢和解毒/修复是跨组织协调的，发生在昼夜（24小时或昼夜）周期中，并且涉及hsp和“I/II期”基因产物，类似于在C. elegans胰岛素样信号通路。我们的初步数据表明，线粒体MnSOD和逆行ROS（H2 O2）信号协调调节HSP 22和I/II期基因表达，代谢周期和寿命的模型。我们还暗示了肿瘤抑制基因p53和性别决定途径在衰老过程中对热休克蛋白22表达的调节。这些过程的动态性质要求我们纵向分析苍蝇衰老和基因表达，以解决基本机制。我们已经开发了新的3D视频技术，以促进在老化过程中的周期性基因表达模式的纵向分析。公共卫生相关性：在人类和模型研究生物果蝇中，衰老与氧化应激反应基因的表达有关。例如，热休克蛋白基因，如热休克蛋白70和热休克蛋白22诱导的组织特异性模式，是类似的人类和苍蝇之间，热休克蛋白基因的表达水平与人类和苍蝇的寿命相关。通过研究衰老果蝇的基因表达，我们希望更好地了解衰老的基本机制，并最终开发出人类衰老相关疾病的干预措施。

DESCRIPTION (provided by applicant): The long-term goal of this research is to understand the regulation of gene expression during aging using the model organism Drosophila melanogaster. Aging in both flies and humans is found to be associated with a tissue-specific induction of oxidative stress response genes, including members of the hsp70 family and hsp22 (alpha-crystallin) family. Heat shock proteins (hsps) are induced in all species in response to heat and other stresses. hsps appear to be involved in prevention and repair of protein damage and can confer increased heat and oxidative stress resistance to many cell types. Drosophila hsp70 and hsp22 genes are induced in a characteristic, tissue-specific pattern during aging. This aging-associated upregulation involves both transcriptional and posttranscriptional mechanisms, and appears to be in part a response to oxidative stress. hsp22 exhibits one of the largest aging-related increases known for a eukaryotic protein (>150-fold). Homologs of hsp70 and hsp22 are upregulated in humans during normal aging and in numerous pathophysiological and aging-related disease states. We hypothesize that altered hsp gene expression is a species-general biomarker of aging and results from a breakdown in normal nuclear-mitochondrial signaling. We propose to study the aging-related transcriptional regulation of Drosophila hsp70 and hsp22 in detail. The research involves genetic and transgenic manipulation of gene expression and life span in Drosophila. The experiments will test several specific hypotheses relating aging and hsp gene expression. The metabolism and detoxification/repair of cells is coordinated across tissues, occurs in diurnal (24 hour or circadian) cycles, and involves hsp and "Phase I/II" gene products similar to those implicated in life span extension downstream of the C. elegans insulin-like signaling pathway. Our preliminary data suggests a model in which mitochondrial MnSOD and retrograde ROS (H2O2) signaling coordinately regulates hsp22 and Phase I/II gene expression, metabolic cycles and life span. We have also implicated the tumor suppressor p53 and the sex-determination pathway in the regulation of hsp22 expression during aging. The dynamic nature of these processes requires that we assay fly aging and gene expression longitudinally to address basic mechanisms. We have developed novel 3D video technology to facilitate longitudinal assay of cyclical gene expression patterns during aging. PUBLIC HEALTH RELEVANCE: In humans and in the model research organism Drosophila, aging is associated with the expression of oxidative stress-response genes. For example, heat shock protein genes such as hsp70 and hsp22 are induced in tissue-specific patterns that are similar between humans and flies, and the level of hsp gene expression correlates with life span in both humans and flies. By studying gene expression in aging Drosophila, we hope to better understand the basic mechanisms of aging, and to ultimately develop interventions for human aging-related diseases.