Labeling cultured cells with 32P(i) and preparing cell lysates for immunoprecipitation

This unit describes (32)P(I) labeling and lysis of cultured cells to be used for subsequent immunoprecipitation of proteins. The procedure is suitable for insect, avian, and mammalian cells and can be used with both adherent and nonadherent cultures. The protocol described is (32)P(I) labeling of adherent or nonadherent (e.g., hematopoietic) cells with subsequent lysis in a detergent buffer. More rigorous lysis conditions to be used for working with proteins that are difficult to solubilize are also described.