Michael J. Ragusa
Assistant Professor of Chemistry
To maintain cellular homeostasis long-lived and toxic cellular components must be degraded. Due to their size, large protein aggregates and long-lived organelles are completely inaccessible to the proteasome, the major protein degradation machinery in the cell. As such, cells have evolved autophagy, a process in which double membrane vesicles engulf cytoplasmic material and target it to the vacuole or lysosome for degradation. The sequestering of autophagic cargo was predominantly thought of as a non-selective process. However, it is now clear that the selection of certain autophagic cargo including mitochondria, peroxisomes, lipid droplets, large protein aggregates and intracellular pathogens can occur through a separate process termed selective autophagy. Defective selective autophagy has been correlated with tumorigenesis, chronic infection and neurodegenerative disease. We are using protein crystallography, small angle X-ray scattering and biochemistry to dissect the molecular mechanisms governing this essential pathway. Gaining an understanding of the molecular mechanisms of selective autophagy will allow for the development of novel therapeutics for the treatment of cancer, neurodegeneration, and infectious diseases.
RE Stanley, MJ Ragusa, JH Hurley. The beginning of the end: How scaffolds and coalescing vesicles nucleate autophagosome biogenesis. Trends in Cell Biology 2014; 24: 73-81.
C Jao*, MJ Ragusa*, RE Stanley, JH Hurley. A HORMA domain in Atg13 mediates PI 3-kinase recruitment in autophagy. Proceedings of the National Academy of Sciences 2013; 110: 5486-5491. *These authors contributed equally to the work
MJ Ragusa*, RE Stanley*, JH Hurley. Architecture of the Atg17 Complex as a Scaffold for Autophagosome Biogenesis. Cell 2012; 151: 1501-1512. *These authors contributed equally to the work
S Baskaran, MJ Ragusa, E Boura, JH Hurley. Two-Site Recognition of Phosphatidylinositol 3-Phosphate by PROPPINs in Autophagy. Molecular Cell 2012; 47: 339-348.
B Dancheck*, MJ Ragusa*, M Allaire, AC Nairn, R Page, W Peti. Molecular Investigations of the Structure and Function of the Protein Phosphatase 1:Spinophilin:Inhibitor-2 Heterotrimeric Complex. Biochemistry 2011; 50: 1238-1246. *These authors contributed equally to the work
MJ Ragusa, M Allaire, AC Nairn, R Page, W Peti. Flexibility in the PP1:spinophilin holoenzyme. FEBS Letters 2011; 585: 36-40.
MJ Ragusa, B Dancheck, DA Critton, AC Nairn, R Page, W Peti. Spinophilin directs protein phosphatase 1 specificity by blocking substrates binding sites. Nature Structural and Molecular Biology 2010; 17: 459-464.