Decreased [20-3H]phorbol-12,13-dibutyrate binding to phospholipase C pretreated epidermal cells.
Incubation of mouse epidermal cells (HEL-37) with phospholipase C (Clostridium perfringens) caused about a 50% decrease in the specific binding of [20-3H]phorbol-12,13-dibutyrate. Phospholipase C caused a decrease in the apparent number of binding sites from 2.86 X 10(5) to 1.21 X 10(5) per cell with little effect on ligand affinity. The decrease was observed with purified phospholipase containing no detectable protease activity, and when cells were fixed with glutaraldehyde. The phorbol-12,13-dibutyrate binding capacity of treated cells was recovered within 4 h incubation in complete medium. The results suggest that not all phorbol ester binding sites are equivalent, with differences arising either from varying phospholipid requirements or from membrane localisation.
D000818:Animals; D001665:Binding Sites / Q000187:drug effects; D002273:Carcinogens / Q000378:metabolism*; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D004817:Epidermis / Q000378:metabolism*; D051379:Mice; D015240:Phorbol 12,13-Dibutyrate; D010703:Phorbol Esters / Q000378:metabolism*; D010704:Phorbols / Q000378:metabolism*; D010740:Phospholipases / Q000494:pharmacology*; D013997:Time Factors; D010738:Type C Phospholipases / Q000494:pharmacology*
D002273:Carcinogens; D010703:Phorbol Esters; D010704:Phorbols; D015240:Phorbol 12,13-Dibutyrate; D010740:Phospholipases; D010738:Type C Phospholipases