| 摘要 |
A process for preparing a phorbol ester receptor which comprises breaking live cells of man, mammal or microorganism containing a phorbol ester receptor, suspending the broken cells in an aqueous solution of a physiologically acceptable salt, collecting fractions containing soluble proteins of cell nuclei and cytoplasms, and chromatographing the collected fractions to recover those fractions which can combine with a phorbol ester but do not have an enzymatic activity similar to that of a calcium-dependent protease. The obtained receptor does not have an enzymatic activity of PKC, can migrate from the cytoplasm to the nucleus of a live cell, is compatible with 12-0-tetradecanoylphorbol-13-acetate, can competitively combine with phorbol dibutyrate, teleocidin, olivoretin, and Aplysia toxin, but cannot combine with okadaic acid, so that this receptor is useful for the study and diagnosis of carcinogenesis. Further it is possible to determine the capability of a phorbol ester receptor of combining with an arbitrary compound by using the receptor obtained according to the present invention and a tumor promoting compound comprising a radioisotope-labeled phorbol ester. |
