Role of Autophagy in Degradation of the Aggregation-Prone Protein that

Description of projects available to graduate students:
Alpha-1-antitrypsin deficiency is the most common genetic cause of liver disease in children and the most frequent genetic diagnosis requiring liver transplantation therapy. In the classical form of this deficiency a point mutation renders the protein aggregation-prone. Instead of being secreted into the blood and body fluids, the mutant antitrypsin Z (ATZ) molecule is retained in the ER in liver cells. Liver inflammation and carcinogenesis is caused by a gain-of-toxic-function mechanism. We have recently found that accumulation of aggregated mutant ATZ activates the autophagic response and that the aggregated protein is degraded by autophagy. Using a novel mouse model with hepatocyte-specific inducible expression of mutant ATZ and gene expression profile analysis we have identified a candidate signaling mechanism for activation of autophagy, regulator of G signaling RGS16. In this project we will examine this issue by breeding the mouse model of AT deficiency to an RGS 16-knockout mouse. The mouse model of AT deficiency has inducible expression of mutant ATZ and is already bred onto a background that makes green fluorescent autophagosomes.

Techniques graduate student will learn:
Cell culture; real-time quantitative PCR; immunocytochemistry; Western blot analysis; metabolic labeling;immunoprecipitation; SDS-PAGE; purification of subcellular organelles and cellular biochemical characterization