Effect of calmodulin inhibitor, Stelazine, on the endocytosis of vitellogenin and transglutaminase activity in Xenopus laevis oöcytes.
The specific endocytosis of vitellogenin was measured in the presence of various concentrations of Stelazine, a specific inhibitor of the calcium regulating protein, calmodulin. Stelazine (200 microM) was found to inhibit the endocytosis of vitellogenin by 63% as determined by decreased uptake of vitellogenin into transitional yolk bodies and yolk platelets. The enzymatic activity of transglutaminase, a calcium-requiring enzyme implicated in receptor-mediated endocytosis, was not affected by these concentrations of Stelazine.
D000217:Acyltransferases / Q000037:antagonists & inhibitors*; D000818:Animals; D002135:Calcium-Binding Proteins / Q000037:antagonists & inhibitors*; D002147:Calmodulin / Q000037:antagonists & inhibitors*; D004705:Endocytosis / Q000187:drug effects; D005260:Female; D008074:Lipoproteins / Q000378:metabolism*; D009865:Oocytes / Q000187:drug effects / Q000201:enzymology*; D010063:Ovum / Q000201:enzymology*; D011700:Putrescine / Q000378:metabolism; D011503:Transglutaminases; D014819:Vitellogenins / Q000378:metabolism*; D014982:Xenopus laevis
D002135:Calcium-Binding Proteins; D002147:Calmodulin; D008074:Lipoproteins; D014819:Vitellogenins; D000217:Acyltransferases; D011503:Transglutaminases; D011700:Putrescine