Endosomal Microautophagy in Drosophila

果蝇内体微自噬

基本信息

批准号：
9246244
负责人：
ANDREAS JENNY
金额：
$ 46.48万
依托单位：
ALBERT EINSTEIN COLLEGE OF MEDICINE, INC
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-02-01 至 2021-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9246244
关键词：
Age Amino Acids Animal Model Animals Autophagocytosis Autophagosome Biochemical Biological Models Biosensor Birds Catabolic Process Cell Culture Techniques Cell physiology Cells Cellular Stress Clinical Complex Cytoplasm DNA Damage Data Development Disease Drosophila genome Drosophila genus Excision Fat Body Functional disorder Genes Genetic Genetic Models Genetic Screening Gluconeogenesis Glycogen Homeostasis Human Ischemia Kidney Kidney Diseases Life Lipids Liver Liver diseases Lysosomes Mammalian Cell Mammals Mediating Membrane Metabolism Modeling Molecular Chaperones Multivesicular Body Nervous system structure Neurodegenerative Disorders Normal Cell Nutrient Organ Organelles Orthologous Gene Pathway interactions Phosphoric Monoester Hydrolases Phosphotransferases Physiological Positioning Attribute Process Protein Isoforms Proteins RNA Splicing RNA interference screen Regulation Reporter Research Role Signal Transduction Sirolimus Sorting - Cell Movement Starvation Stress System Testing Tissues Transgenic Organisms Vesicle Yeasts age related biological adaptation to stress energy balance fly in vivo insulin signaling knock-down late endosome lipid metabolism multicatalytic endopeptidase complex novel novel strategies prevent protein aggregate protein degradation receptor sensor stressor treatment strategy

项目摘要

Endosomal Microautophagy in Drosophila Proper turnover of proteins and organelles is essential for normal cell function. Damaged or altered cytosolic proteins are cleared by the proteasome and autophagy. Importantly, autophagy has the additional role of providing nutrients to cells under stress conditions such as starvation, and is thus essential for energy balance. The liver is one of the main regulators of lipids in the body and has major roles in metabolism such as gluconeogenesis, a process that is particularly dependent on amino acids generated by autophagic degradation of cellular proteins under starvation or stress. Furthermore, removal of damaged organelles and aggregated proteins is essential to protect liver and kidneys against age related disorders. Macroautophagy (MA), Chaperone mediated Autophagy (CMA) and endosomal Microautophagy (eMI) are the three major forms of autophagy. MA engulfs bulk-regions of cytoplasm including organelles in a double membrane vesicle (autophagosome). Autophagosome fusion with lysosomes leads to the degradation of the engulfed material. Less is known about CMA and eMI, which mostly degrade proteins containing a targeting motif (KFERQ related sequences) that is recognized by the cytoplasmic Hsc70. During eMI, which to date has only been characterized biochemically and by EM, KFERQ containing substrates bound to Hsc70 are taken up into multivesicular bodies/late endosomes in an ESCRT machinery dependent process and degraded. Previously, the existence of eMI beyond mammals was unknown and there is currently no in vivo system to study mammalian eMI. Hence, the genetic power of model organisms such as Drosophila have not been exploited for the study of KFERQ- dependent forms of autophagy. Using a fluorescently tagged model substrate expressed in transgenic flies, we developed a model system to study starvation inducible eMI in vivo. Using this system, we will assess the physiological function and regulation of eMI by starvation and other forms of cellular stress. Furthermore, we will characterize regulators of eMI that we have identified in a genetic screen.

果蝇中的内体微自噬蛋白质和细胞器的适当周转对于正常细胞功能至关重要。蛋白酶体和自噬可以清除受损或改变的胞质蛋白。重要的是，自噬具有向压力下细胞提供营养的额外作用饥饿等条件，因此对于能量平衡至关重要。肝脏是一个体内脂质的主要调节剂，在代谢中具有重要作用糖生成，该过程特别依赖于由在饥饿或应激下，细胞蛋白的自噬降解。此外，去除受损细胞器和聚集蛋白对于保护肝脏至关重要针对年龄相关疾病的肾脏。大噬菌（MA），伴侣介导的自噬（CMA）和内体微自噬（EMI）是自噬的三种主要形式。马吞噬了散装区域细胞质的细胞质，包括双膜囊泡（自噬体）中的细胞器。与溶酶体的自噬体融合会导致吞噬材料的降解。关于CMA和EMI知之甚少，这些CMA和EMI主要降解含有A的蛋白靶向基序（KFERQ相关序列），由细胞质HSC70识别。在EMI期间，迄今为止仅在生化和EM上表征的EMI，与HSC70结合的基板的KFERQ被占多个依赖于ESCRT机械过程中的身体/晚期内体并降解。以前，哺乳动物以外的EMI的存在尚不清楚，目前有没有研究哺乳动物EMI的体内系统。因此，模型的遗传力量尚未利用果蝇等生物进行KFERQ-的研究自噬的依赖形式。使用在转基因蝇中表达的荧光标记的模型底物，我们开发了一个模型系统，用于研究体内饥饿诱导的EMI。使用此系统，我们将通过饥饿和其他细胞应激的形式。此外，我们将表征我们的EMI监管机构在遗传筛选中已经鉴定出来。