GEL Domain |
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Class:Cytoskeletal modulation |
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Structure:
Individual GEL domains consist of a central five- or six-stranded b-sheet sandwiched between two a-helices that are perpendicular to one another. Single GEL domains can bind actin, however, in the protein gelsolin, three GEL domains act in concert to permit calcium-regulated actin binding. Calcium binding to gelsolin GEL domains induces a conformational reorganization that cleaves apart the continuous b-sheet core of GEL4 and GEL5 and exposes the actin-binding site on GEL4. Gelsolin contain two sets of triple-GEL domains, allowing two actin molecules to be bound, thus enabling severing and capping of actin filaments.
Structure reference: Robinson, R.C. et al. (1999) Science. 286(5446): 1939-1942. Choe, H. et al. (2002) J. Mol. Biol. 324(4): 691-702. PDB: 1H1V.
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Domain binding and function: Also know as the gelsolin/severin/villin homology domain, the gelsolin homology domain (GEL) is a 120 - 150 amino acid domain found in a variety of proteins involved in cytoskeletal regulation, particularly in proteins that function in actin severing. The GEL domain has both calcium binding and actin binding activity, such that actin binding is calcium regulated. The gelsolin protein, composed of six GEL domains, binds to the barbed ends of actin filaments preventing monomer exchange and acting as an end-blocking or capping protein for the actin filament. In addition, gelsolin can promote actin nucleation to create new filaments and sever existing filaments.
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Examples of Proteins:
GEL Domain Proteins |
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Binding partner |
Gelsolin |  |
Ca2+ and F-actin |
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Referenced in part on Cell Signaling Technology Website, Reference Section on Protein Domains. We gratefully acknowledge the following contributors:
Piers Nash1, Dan Lin3, Kathleen Binns2, Clark Wells2, Rob Ingham2, Terry Kubiseski2, Bernard Liu1, Matt Smith2,3, Ivan Blasutig2,3, Maria Sierra1, Caesar Lim2,3, Michael Arc1, Jim Fawcett2 and Tony Pawson2,3.
1. Ben May Institute for Cancer Research, The University of Chicago, Chicago, Illinois, 60637, USA
2. Program in Molecular Biology and Cancer, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, M5G 1X5, Canada
3. Department of Molecular and Medical Genetics, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
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