Role of protein kinase C activators and inhibitors, calmodulin antagonists and membrane sialic acids in polyamine transport in murine leukemia cells.
The effects of activators and inhibitors of protein kinase C (phorbol esters and H-7) and antagonist to calmodulin (TFP) on polyamine transport in murine leukemia (L1210) cells are investigated. Phorbol esters and H-7 are found to enhance and curtail the uptake of 14C-Spermidine (Spd) respectively in L1210 cells. TFP also inhibits the uptake process. After desialation of cells with neuraminidase, phorbol esters are found to further increase the uptake of 14C-Spd by 35% compared to untreated cells. The sialic acid contents of the cells are regenerated by incubation with 14C-glucosamine for 18 hours. The regenerated cells mimic like untreated cells for the uptake of 14C-Spd i.e. after regeneration of sialic acids, the Spd uptake is curtailed significantly in comparison with desialated cells. Phorbol esters are found to enhance the activity of transglutaminase present in L1210 cells while H-7 and TFP exhibit reverse effects. The possible role of phorbol esters, H-7 and TFP and their effects on transglutaminase activity in relation with Spd transport process are discussed.
Khan
N A
NA
Quemener
V
V
Moulinoux
J P
JP
D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D002147:Calmodulin / Q000037:antagonists & inhibitors; D007939:Leukemia L1210 / Q000378:metabolism*; D051379:Mice; D011073:Polyamines / Q000493:pharmacokinetics*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism; D012794:Sialic Acids / Q000378:metabolism; D011503:Transglutaminases / Q000378:metabolism; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism
D002147:Calmodulin; D011073:Polyamines; D012794:Sialic Acids; D011503:Transglutaminases; D011493:Protein Kinase C