Inositol 1,3,4,5-tetrakisphosphate stimulates the initiation of DNA synthesis in Ca2+-deprived rat liver cells.
The G1-S boundary of non-neoplastic cells requires extracellular Ca2+ for successful transition. Inositol 1,3,4,5-tetrakisphosphate but not inositol 1,4,5-trisphosphate can partially replace Ca2+ and stimulate the initiation of DNA synthesis of Ca2+-deprived T51B rat liver cells but only if sufficient extracellular Ca2+ (i.e., 0.075 mM) is present. The potent tumor promoter and protein kinase C activator 12-O-tetradecanoylphorbol acetate is also capable of replacing extracellular Ca2+ and partially stimulating the initiation of DNA synthesis. In addition, both inositol-1,3,4,5-tetrakisphosphate and 12-O-tetradecanoylphorbol acetate added together elicit a full DNA synthetic response.
Hill
T D
TD
Cancer Research Center of Hawaii, University of Hawaii Honolulu 96813.
Zwiller
J
J
Boynton
A L
AL
D000818:Animals; D002118:Calcium / Q000172:deficiency* / Q000494:pharmacology; D002453:Cell Cycle / Q000187:drug effects; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis*; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D007295:Inositol Phosphates / Q000494:pharmacology*; D008099:Liver / Q000166:cytology* / Q000378:metabolism; D011493:Protein Kinase C / Q000378:metabolism; D051381:Rats; D013403:Sugar Phosphates / Q000494:pharmacology*
D007295:Inositol Phosphates; D013403:Sugar Phosphates; C081655:inositol-1,3,4,5-tetrakisphosphate; D004247:DNA; D011493:Protein Kinase C; D002118:Calcium