Abstract
Osteopontin (OPN) and bone sialoprotein (BSP) are phosphorylated glycoproteins that, together with osteonectin/secreted protein, acidic, rich in cysteine (SPARC) and osteocalcin, comprise the major non-collagen proteins of bone. Although phosphorylation of OPN and BSP, which is known to influence the biological properties of these proteins, has been shown to occur intracellularly, recent studies have demonstrated ectokinase activity in bone cell populations [Mikuni-Takagaki, Kakai, Satoyoshi, Kawano, Suzuki, Kawase and Saito (1995) J. Bone Miner. Res. 10, 231-241]. To determine whether OPN and BSP are phosphorylated by ectokinase activity we have used [gamma-32P]ATP and [gamma-32P]GTP as cell-impenetrable phosphate donors to analyse for ectokinase activity in osteoblastic UMR106.06 cells and fetal rat calvarial cells (FRCCs). By pulse-labelling confluent cells with radiolabelled nucleotides, the phosphorylation of endogenous and exogenously added OPN and BSP was demonstrated together with the labelling of a number of cell surface proteins. These phosphorylation reactions were inhibited by a cell-impermeable ectokinase inhibitor, K252b, and cell surface phosphorylation was also inhibited by exogenously added OPN and BSP substrat...Continue Reading
Citations
Oct 6, 2000·Critical Reviews in Oral Biology and Medicine : an Official Publication of the American Association of Oral Biologists·J SodekM D McKee
Dec 17, 2005·Journal of Experimental Zoology. Part B, Molecular and Developmental Evolution·Kazuhiko Kawasaki, Kenneth M Weiss
Dec 8, 2006·Proteomics·Karlheinz MannMatthias Mann
Mar 21, 2018·Biomedical Reports·Mathias Montenarh, Claudia Götz
Jun 5, 2007·The Journal of Biological Chemistry·Elena P ZiminaLeena Bruckner-Tuderman
Jul 13, 2018·Journal of Bone and Mineral Research : the Official Journal of the American Society for Bone and Mineral Research·Grażyna E Sroga, Deepak Vashishth
Apr 4, 2019·IUBMB Life·Brenden C ParkVincent S Tagliabracci
Apr 12, 2000·Critical Reviews in Oral Biology and Medicine : an Official Publication of the American Association of Oral Biologists·B GanssJ Sodek
Jun 14, 2000·American Journal of Physiology. Heart and Circulatory Physiology·A BabinskaE Kornecki
Nov 11, 2005·Proteomics·Stephen ChivasaAntoni R Slabas
Dec 20, 2012·Science Signaling·Garif Yalak, Viola Vogel
Jun 24, 2003·Journal of Bone and Mineral Research : the Official Journal of the American Society for Bone and Mineral Research·Kristen JohnsonRobert Terkeltaub
Oct 15, 2003·Arthritis and Rheumatism·Maryse PicherGreta M Lee
Sep 9, 2006·The Journal of Biological Chemistry·Keiichi InoueShigeyoshi Itohara
Jan 1, 1998·Journal of Cellular Biochemistry·David T Denhardt, Masaki Noda
Nov 5, 1999·Trends in Pharmacological Sciences·F A RedegeldM V Sitkovsky
Feb 14, 2004·Bone·P S N RoweG R Mundy
Jan 25, 2005·Bone·Peter S N RoweGloria E Gutierrez
Aug 3, 2007·Bone·Yukiko NakanoMari T Kaartinen
Jan 19, 2010·Bone·William N Addison, Marc D McKee