title: Preparation of cross-linked cellular extracts with formaldehyde.
abstract: Formaldehyde is a powerful cross-linking agent that elicits protein-protein and protein-nucleic acid cross-links. This protocol describes the formaldehyde cross-linking of intact cells followed by either the preparation of a whole-cell extract by sonication or the preparation of nuclear and cytoplasmic extracts by fractionation. Cross-linked extracts are treated with high salt or sodium dodecyl sulfate (SDS) to disrupt non-cross-linked aggregates. Protein-protein and protein-nucleic acid interactions can then be studied by purifying the components of interest from the extracts (e.g., using immunoprecipitation). Formaldehyde cross-links are reversible by heat.
authors.forename: Timothy W
authors.initials: TW
authors.lastname: Nilsen
mesh_terms: D000818:Animals; D002457:Cell Extracts; D002478:Cells, Cultured / Q000187:drug effects* / Q000648:ultrastructure; D003432:Cross-Linking Reagents / Q000494:pharmacology*; D005557:Formaldehyde / Q000494:pharmacology*; D013010:Sonication
chemical_list: D002457:Cell Extracts; D003432:Cross-Linking Reagents; D005557:Formaldehyde