The state of the actin cytoskeleton determines its association with gephyrin: role of ena/VASP family members.
The role the cytoskeleton plays in generating and/or maintaining gephyrin-dependent receptor clusters at inhibitory synapses is poorly understood. Here, the effects of actin cytoskeleton disruption were investigated in eGFP-gephyrin-transfected cells and hippocampal neurons. While gephyrin was not associated with microfilaments in transfected cells, it colocalized with G-actin and cytochalasin-D-induced F-actin patches. The linker region between the MoeA and MogA homology domains of gephyrin was required for colocalization with F-actin patches and for the binding of gephyrin to ena/VASP, an actin anti-capping factor that, in vitro, caused gephyrin binding to polymerized actin. In hippocampal neurons, treatment with cytochalasin D resulted in the redistribution of the neuronal ena/VASP homologue Mena into actin patches and, at early stages of development, a reduction in the number of gephyrin clusters. Our data suggest that Mena binding to F-actin allows for gephyrin recruitment to the leading edge of uncapped actin filaments.
Bausen
Melanie
M
Department of Neurochemistry, Max-Planck Institute for Brain Research, 60528 Frankfurt, Germany.
Fuhrmann
Jens C
JC
Betz
Heinrich
H
O'sullivan
Gregory A
GA
D008841:Actin Cytoskeleton / Q000378:metabolism; D000199:Actins / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D015638:Cytochalasin D / Q000494:pharmacology; D003599:Cytoskeleton / Q000187:drug effects / Q000378:metabolism*; D047630:Depsipeptides / Q000494:pharmacology; D006624:Hippocampus / Q000166:cytology; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism*; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D019384:Nucleic Acid Synthesis Inhibitors / Q000494:pharmacology; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D013569:Synapses / Q000378:metabolism / Q000648:ultrastructure; D013844:Thiazoles / Q000494:pharmacology; D053778:Thiazolidines; D000098662:Vasodilator-Stimulated Phosphoprotein
D000199:Actins; D000970:Antineoplastic Agents; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002352:Carrier Proteins; D015815:Cell Adhesion Molecules; D047630:Depsipeptides; D008565:Membrane Proteins; D008840:Microfilament Proteins; D019384:Nucleic Acid Synthesis Inhibitors; D010750:Phosphoproteins; D011993:Recombinant Fusion Proteins; D013844:Thiazoles; D053778:Thiazolidines; C073441:gephyrin; D000098662:Vasodilator-Stimulated Phosphoprotein; C057531:jasplakinolide; D015638:Cytochalasin D; C037067:latrunculin A