Calpain II colocalizes with detergent-insoluble rafts on human and Jurkat T-cells
| Autor: | Kathy Forrest, L.Kevin Overstreet, Lorri A. Morford, William H. Brooks, Barbara Logan, Thomas L. Roszman, Jens Goebel |
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| Rok vydání: | 2002 |
| Předmět: |
biology
Calpain T-Lymphocytes Detergents Biophysics chemistry.chemical_element Cell Biology Calcium Biochemistry Cysteine protease Jurkat cells Immunological synapse Cell biology Jurkat Cells Membrane Lipids chemistry biology.protein Humans Signal transduction Cytoskeleton Molecular Biology Lipid raft |
| Zdroj: | Biochemical and Biophysical Research Communications. 295:540-546 |
| ISSN: | 0006-291X |
| DOI: | 10.1016/s0006-291x(02)00676-9 |
| Popis: | Calpain, a calcium-dependent cysteine protease, is known to associate with the T-cell plasma membrane and subsequently cleave a number of cytoskeletal-associated proteins. In this study, we report the novel observation that calpain II, but not calpain I, associates with membrane lipid rafts on human peripheral blood T-cells and Jurkat cells. Raft-associated calpain activity is enhanced with exogenous calcium and inhibited with calpeptin, a specific inhibitor of calpain activity. In addition, we demonstrate that calpain cleaves the cytoskeletal-associated protein, talin, during the first 30-min after cell stimulation. We propose that lipid raft associated-calpain II could function in early TCR signaling to facilitate immune synapse formation through cytoskeletal remodeling mechanisms. Hence, we demonstrate that the positioning of calpain II within T-cell lipid rafts strategically places it in close proximity to known calpain substrates that are cleaved during Ag-specific T-cell signaling and immune synapse formation. |
| Databáze: | OpenAIRE |
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