Autophagy is a fundamental mechanism for maintenance of cellular homeostasis through self-digestion. Abnormal autophagy is closely related to many human disorders such as cancer, aging, and neurodegeneration. A deep mechanistic understanding of autophagy is crucial for the development of therapeutic strategies against these diseases. Autophagosome biogenesis is intimately associated with the capture and destruction of macromolecules whose turnover is executed in the autophagic process. It entails a spatiotemporal orchestration of protein-membrane interactions which is not fully understood. Dr. Ge has established a functional assay based on cell-free reconstitution of autophagosome biogenesis, through which he has made a further step towards the understanding of autophagosome biogenesis by identifying the ER-Golgi intermediate compartment as a key membrane source of the autophagosome. In this study, Dr. Ge seeks to extend this functional assay to decipher the underlying molecular actions generating the autophagosome.
In Aim 1, Dr. Ge will establish a set of new cell-free assays together with cell-imaging and genetics to investigate the initial step of autophagosome biogenesis by focusing on an autophagic signal-induced membrane mobilization event generating the autophagic membrane precursor.
In Aim 2, Dr. Ge will develop a systematic protein fractionation approach to identify novel protein factors in autophagosome biogenesis, as well as to define the functional role of each factor in the protein-membrane network of autophagy. Dr. Ge's long term goal is to understand the molecular nature of autophagy in physiological and pathological settings for the purpose of autophagy-modulating therapy. Training in the mentored phase will prepare Dr. Ge to lead an independent research team using biochemical reconstitution, cell imaging, genetic manipulation, and mass spectrometry to address the fundamental questions of autophagy, as well as to understand the pathogenesis of autophagy-related diseases. Training under this award will include: learning new techniques, such as super-resolution imaging, electron microscopy and quantitative mass spectrometry, acquiring more experience in biochemical reconstitution and fractionation, and expanding knowledge and expertise in autophagy, as well as teaching and writing. Completion of the research and training will greatly facilitate Dr. Ge's transition and success as an independent investigator.

Public Health Relevance

Autophagy dysfunction contributes to multiple human disorders including cancer, aging, neurodegeneration, myopathy, and immune diseases. Deciphering the molecular nature of autophagy would facilitate the development of effective therapeutic strategies for the treatment of these diseases. This project seeks to dissect the mechanism of autophagosome biogenesis, a key step of autophagy.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Career Transition Award (K99)
Project #
5K99GM114397-02
Application #
9069023
Study Section
Special Emphasis Panel (ZGM1)
Program Officer
Flicker, Paula F
Project Start
2015-06-01
Project End
2017-05-31
Budget Start
2016-06-01
Budget End
2017-05-31
Support Year
2
Fiscal Year
2016
Total Cost
Indirect Cost
Name
University of California Berkeley
Department
Biochemistry
Type
Schools of Arts and Sciences
DUNS #
124726725
City
Berkeley
State
CA
Country
United States
Zip Code
94704
Zhang, Min; Liu, Dawei; Ge, Liang (2017) In Vitro Dissection of Autophagy. Curr Protoc Cell Biol 77:11.23.1-11.23.17
Ge, Liang; Zhang, Min; Kenny, Samuel J et al. (2017) Remodeling of ER-exit sites initiates a membrane supply pathway for autophagosome biogenesis. EMBO Rep 18:1586-1603
Joo, Joung Hyuck; Wang, Bo; Frankel, Elisa et al. (2016) The Noncanonical Role of ULK/ATG1 in ER-to-Golgi Trafficking Is Essential for Cellular Homeostasis. Mol Cell 62:491-506
Brier, Livia Wilz; Zhang, Min; Ge, Liang (2016) Mechanistically Dissecting Autophagy: Insights from In Vitro Reconstitution. J Mol Biol 428:1700-13
Ge, Liang; Wilz, Livia; Schekman, Randy (2015) Biogenesis of autophagosomal precursors for LC3 lipidation from the ER-Golgi intermediate compartment. Autophagy 11:2372-4
Zhang, Min; Kenny, Samuel J; Ge, Liang et al. (2015) Translocation of interleukin-1? into a vesicle intermediate in autophagy-mediated secretion. Elife 4:
Ge, Liang; Zhang, Min; Schekman, Randy (2014) Phosphatidylinositol 3-kinase and COPII generate LC3 lipidation vesicles from the ER-Golgi intermediate compartment. Elife 3:e04135