Cargo-responsive mechanisms in autophagy

项目摘要/摘要 去除有毒或不需要的细胞结构--如蛋白质聚集体、细胞内病原体 以及细胞器受损--这是真核细胞面临的一个根本挑战。为了消除这些结构， 对于蛋白酶体来说太大和太复杂，细胞需要替代的降解途径， 自噬。该领域的主要观点是，所有的自噬靶标都会被共同的 机制。然而，这种理解主要来自于对几个模型底物的研究， 未经证实的假设，即其他货物的行为类似。为了测试这个模型，我开发了一个面板 适用于基因筛查、定量显微镜和生化的货物特异性自噬记者 操纵。通过这种方法，我发现自噬货物(及其受体)对 自噬，即不同的货物可以通过不同的机制诱导自噬。在这个过程中，我 发现了一组新的蛋白质，有助于货物选择和自噬启动。展望未来， 我们工作的广泛目标是应用我们以受体为中心的范例来揭示新的自噬机制， 剖析自噬的生理影响(S)，并阐明迄今未知的溶酶体运输 小路。我们希望我们的研究将重塑自噬因子如何发挥作用的传统观点，使其成为更 复杂的重叠机制网络，确保强大的细胞质到溶酶体的传递。为了做到这一点，我们 将揭示自噬的保守原理，并有助于我们对自噬失调的理解 疾病。

Project Summary/Abstract The removal of toxic or unwanted cellular structures – such as protein aggregates, intracellular pathogens and damaged organelles – presents a fundamental challenge for eukaryotic cells. To eliminate these structures, which are too large and too complex for the proteasome, cells require an alternative degradation pathway, autophagy. The predominant view in the field is that all autophagy targets are degraded by a common mechanism. However, this understanding comes primarily from studies of only a few model substrates, with the unsubstantiated assumption that other cargoes behave similarly. To test this model, I developed a panel of cargo-specific autophagy reporters amenable to genetic screening, quantitative microscopy, and biochemical manipulation. By this approach, I discovered that autophagy cargo (and their receptors) are instructive for autophagy, such that different cargoes can induce autophagy via different mechanisms. In the process, I discovered a new cohort of proteins that facilitate cargo selection and autophagosome initiation. Going forward, the broad goal of our work is to apply our receptor-centric paradigm to reveal new autophagy mechanisms, dissect the physiological impact(s) of autophagy, and elucidate heretofore unknown lysosomal trafficking pathways. We expect our studies to reshape the traditional view of how autophagy factors function into a more complex web of overlapping mechanisms that ensure robust cytoplasm-to-lysosome delivery. In doing so, we will reveal conserved principles of autophagy and inform our understanding of autophagy dysregulation in disease.