Abstract |
Postnatal microcephaly, intellectual disability, and progressive retinal dystrophy are major features of autosomal recessive Cohen syndrome, which is caused by mutations in the gene COH1 (VPS13B). We have recently identified COH1 as a Golgi-enriched scaffold protein that contributes to the structural maintenance and function of the Golgi complex. Here, we show that association of COH1 with the Golgi complex depends on the small GTPase RAB6. RNAi-mediated knockdown of RAB6A/A' prevents the localization of COH1 to the Golgi complex. Expression of the constitutively inactive RAB6_T27N mutant led to an increased solubilization of COH1 from lipid membrane preparations. Co-IP experiments confirmed the physical interaction of COH1 with RAB6 that preferentially occurred with the constitutively active RAB6_Q72L mutants. Depletion of COH1 in primary neurons negatively interfered with neurite outgrowth, indicating a causal link between the integrity of the Golgi complex and axonal outgrowth. We conclude that COH1 is a RAB6 effector protein and that reduced brain size in Cohen syndrome patients likely results from impaired COH1 function at the Golgi complex, causing decreased neuritogenesis.
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Authors | Wenke Seifert, Jirko Kühnisch, Tanja Maritzen, Stefanie Lommatzsch, Hans Christian Hennies, Sebastian Bachmann, Denise Horn, Volker Haucke |
Journal | The Journal of biological chemistry
(J Biol Chem)
Vol. 290
Issue 6
Pg. 3349-58
(Feb 06 2015)
ISSN: 1083-351X [Electronic] United States |
PMID | 25492866
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Copyright | © 2015 by The American Society for Biochemistry and Molecular Biology, Inc. |
Chemical References |
- Rab6 protein
- VPS13B protein, human
- Vesicular Transport Proteins
- rab GTP-Binding Proteins
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Topics |
- Animals
- Cells, Cultured
- Golgi Apparatus
(metabolism)
- HEK293 Cells
- HeLa Cells
- Humans
- Neurites
(metabolism)
- Protein Binding
- Protein Transport
- Rats
- Vesicular Transport Proteins
(genetics, metabolism)
- rab GTP-Binding Proteins
(genetics, metabolism)
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