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Lipid Vesicle-mediated Affinity Chromatography using Magnetic Activated Cell Sorting (LIMACS): a Novel Method to Analyze Protein-lipid Interaction
Published on: April 26, 2011
CERT-mediated trafficking of ceramide
Kentaro Hanada1, Keigo Kumagai, Nario Tomishige
1Department of Biochemistry, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan. hanak@nih.go.jp
Biochimica Et Biophysica Acta
|May 7, 2009
Summary
The CERT protein facilitates ceramide transport from the endoplasmic reticulum to the Golgi apparatus for sphingolipid synthesis. This non-vesicular trafficking is crucial for membrane biogenesis and occurs at ER-Golgi membrane contact sites.
Area of Science:
- Cell Biology
- Biochemistry
- Molecular Biology
Background:
- Lipid transport is essential for membrane biogenesis.
- Sphingolipid synthesis involves ceramide transport from the ER to the Golgi.
- CERT is a key protein mediating this ceramide trafficking.
Purpose of the Study:
- To elucidate the mechanism of ceramide transport by CERT.
- To identify the functional domains of CERT involved in ER-to-Golgi trafficking.
- To understand the role of membrane contact sites in efficient ceramide transport.
Main Methods:
- Analysis of CERT protein domains and motifs.
- Investigating protein-protein interactions (e.g., CERT-VAP).
- Studying ceramide transport in mammalian cells.
Main Results:
- CERT utilizes its START domain for inter-membrane ceramide transfer.
- The PH domain targets CERT to the Golgi, while the FFAT motif interacts with VAP at the ER.
- Phosphorylation of the serine-repeat motif regulates CERT activity.
- CERT-mediated ceramide transport occurs non-vesicularly at ER-Golgi membrane contact sites.
Conclusions:
- CERT is a multi-domain protein essential for non-vesicular ceramide transport.
- Efficient trafficking relies on specific domains and interactions at membrane contact sites.
- Regulation of CERT activity by phosphorylation is critical for sphingolipid metabolism.
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