title: A specific increase in inositol 1,4,5-trisphosphate 3-kinase B expression upon differentiation of human embryonic stem cells.
abstract: Human embryonic stem cells (hESCs) are of great hope for regenerative medicine due to their dual pluripotency and self-renewal properties. We report a comparison of inositol phosphate (InsP(s)) production in undifferentiated, differentiated hESCs and in two cancer cell lines, Ntera2 cells, a human embryonal carcinoma cell (hECC) line and HeLa cells. To evaluate the potential impact of InsP(s) in differentiation, hESCs were spontaneously differentiated in culture for two weeks. The distribution of the different InsP(s) was affected upon differentiation: the level of highly phosphorylated InsP(s) was decreased. In contrast, the total level of phosphoinositides (PI) was increased. Using real time quantitative PCR (qPCR), the mRNA expression of several enzymes of the metabolism of InsP(s) was determined: a specific increase in inositol 1,4,5-trisphosphate 3-kinase A and B (ITPKA and ITPKB) was observed upon hESCs spontaneous differentiation. Ins(1,4,5)P(3) 3-kinase activity, undetectable in undifferentiated hESCs, increased upon differentiation. The same observation was made by Western blotting using an antibody directed against human ITPKB. This is the first report showing the potential implication of soluble InsP(s) in hESCs and possible function of isoenzymes of the inositol trisphosphate 3-kinase family in differentiation.
authors.affiliation: Research Laboratory on Human Reproduction, Université Libre de Bruxelles, Brussels, Belgium.
authors.forename: Catherine
authors.initials: C
authors.lastname: Hoofd
authors.forename: Fabienne
authors.initials: F
authors.lastname: Devreker
authors.forename: Laurence
authors.initials: L
authors.lastname: Deneubourg
authors.forename: Sandrine
authors.initials: S
authors.lastname: Deleu
authors.forename: Thi Mai Uyen
authors.initials: TM
authors.lastname: Nguyen
authors.forename: Karen
authors.initials: K
authors.lastname: Sermon
authors.forename: Yvon
authors.initials: Y
authors.lastname: Englert
authors.forename: Christophe
authors.initials: C
authors.lastname: Erneux
mesh_terms: D002454:Cell Differentiation / Q000235:genetics*; D053595:Embryonic Stem Cells / Q000201:enzymology / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D006367:HeLa Cells; D006801:Humans; D007295:Inositol Phosphates / Q000096:biosynthesis; D010716:Phosphatidylinositols / Q000096:biosynthesis; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000378:metabolism*
chemical_list: D007295:Inositol Phosphates; D010716:Phosphatidylinositols; D017853:Phosphotransferases (Alcohol Group Acceptor); C051038:Inositol 1,4,5-trisphosphate 3-kinase