Inositol 1,3,4,5-tetrakisphosphate is essential for T lymphocyte development.
Inositol 1,4,5-trisphosphate (Ins(1,4,5)P(3)) is phosphorylated by Ins(1,4,5)P(3) 3-kinase, generating inositol 1,3,4,5-tetrakisphosphate (Ins(1,3,4,5)P(4)). The physiological function of Ins(1,3,4,5)P(4) is still unclear, but it has been reported to be a potential modulator of calcium mobilization. Disruption of the gene encoding the ubiquitously expressed Ins(1,4,5)P(3) 3-kinase isoform B (Itpkb) in mice caused a severe T cell deficiency due to major alterations in thymocyte responsiveness and selection. However, we were unable to detect substantial defects in Ins(1,4,5)P(3) amounts or calcium mobilization in Itpkb(-/-) thymocytes. These data indicate that Itpkb and Ins(1,3,4,5)P(4) define an essential signaling pathway for T cell precursor responsiveness and development.
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology*; D007295:Inositol Phosphates / Q000172:deficiency / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic; D050778:NFATC Transcription Factors; D010770:Phosphotransferases / Q000172:deficiency / Q000235:genetics; D013601:T-Lymphocytes / Q000502:physiology*
D007295:Inositol Phosphates; D050778:NFATC Transcription Factors; C494009:Nfatc3 protein, mouse; C081655:inositol-1,3,4,5-tetrakisphosphate; D010770:Phosphotransferases; D002118:Calcium