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Analyzing folding and degradation of metabolically labelled polypeptides by conventional and diagonal sodium dodecyl sulfate-polyacrylamide gel electrophoresis
Biological Procedures Online volume 7, pages 136–143 (2005)
Efficient protein folding and quality control are essential for unperturbed cell viability. Defects in these processes may lead to production of aberrant polypeptides that are either degraded leading to “loss-of-function” phenotypes, or deposited in or outside cells leading to “gain-of-toxic-function” phenotypes. Elucidation of molecular mechanisms regulating folding and quality control of newly synthesized polypeptides is therefore of greatest interest. Here we describe protocols for metabolic labelling of transfected/infected mammalian cells with [35S]-methionine and [35S]-cysteine, for immunoisolation from detergent extracts of the selected model proteins and for the investigation of the model polypeptide’s intracellular fate in response to chaperone-deletions or to cell exposure to folding or degradation inhibitors.
ER-associated protein degradation
influenza virus hemagglutinin
sodium dodecyl sulfate-polyacrylamide gel electrophoresis
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Soldà, T., Olivari, S. & Molinari, M. Analyzing folding and degradation of metabolically labelled polypeptides by conventional and diagonal sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Biol. Proced. Online 7, 136–143 (2005). https://doi.org/10.1251/bpo111
- Endoplasmic Reticulum
- Molecular Chaperones
- Protein Folding