2013 Fiscal Year Final Research Report
Elucidation of the mode of action of Atg12-Atg5 conjugate in autophagy
| Project/Area Number |
24770092
|
|---|
| Research Category |
Grant-in-Aid for Young Scientists (B)
|
| Allocation Type | Multi-year Fund |
|---|
| Research Field |
Structural biochemistry
|
|---|
| Research Institution | Tokyo Institute of Technology |
|---|
Principal Investigator |
NAKATOGAWA Machiko 東京工業大学, フロンティア研究機構, 先進研究員 (90402461)
|
|---|
| Project Period (FY) |
2012-04-01 – 2014-03-31
|
| Keywords | ユビキチン様タンパク質 / E3酵素 / オートファジー |
|---|
| Research Abstract |
Autophagy is a bulk degradation system, which involves the formation of a double-membrane vesicle called autophagosome. Autophagosome formation requires two ubiquitin-like proteins, Atg8 and Atg12. They are conjugated to the phosphatidylethanolamine (PE) and Atg5, respectively, via a series of enzymatic reactions with E1 and E2 enzyme. In this study, we elucidated the mode of action of Atg12-Atg5 as an E3 enzyme in the Atg8-PE conjugation reaction. We established a biochemical assay based on the structural information to determine the configuration of the catalytic center of Atg3, which is an E2 enzyme in Atg8-PE conjugation reaction. This approach revealed that Atg12-Atg5 conjugate induces a conformational change in the catalytic center of Atg3 to enhance its E2 activity. Moreover, mutational analyses indicated how the activity of Atg3 is suppressed in the absence of Atg12-Atg5 conjugate. We are attempting to analyze the crystal structure of Atg12-Atg5 conjugate/Atg3 complex.
|
