title: cAMP induces phosphorylation of a 40-kDa nuclear protein which is distinct from CREB during chondrogenesis of chick limb bud mesenchymal cells in vitro.
abstract: We examined the effect of cAMP on the phosphorylation of intracellular proteins in cultured chondroblasts to understand the stimulatory role of intracellular cAMP in chondrogenesis of chick limb bud mesenchymal cells. A 40-kDa protein was remarkably phosphorylated by cAMP and the phosphorylation was completely blocked by an inhibitor of cAMP-dependent protein kinase. The phosphorylation of the 40-kDa protein was maximum at early stage of chondrogenesis (i.e., 24 hr of culture) which is consistent with the changes in the level of intracellular cAMP. The 40-kDa phosphoprotein was exclusively located in the nuclear parts of chondroblast but distinct from cAMP response element binding protein.
authors.affiliation: Department of Biology, College of Natural Sciences, Kyungpook National University, Taequ, Korea.
authors.forename: S Y
authors.initials: SY
authors.lastname: Park
authors.forename: J C
authors.initials: JC
authors.lastname: Jung
authors.forename: S D
authors.initials: SD
authors.lastname: Kim
authors.forename: Y S
authors.initials: YS
authors.lastname: Lee
authors.forename: T K
authors.initials: TK
authors.lastname: Park
authors.forename: S S
authors.initials: SS
authors.lastname: Kang
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000196:embryology / Q000378:metabolism*; D002478:Cells, Cultured; D002642:Chick Embryo; D003238:Connective Tissue / Q000196:embryology / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism*; D017362:Cyclic AMP Response Element-Binding Protein / Q000302:isolation & purification / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D008970:Molecular Weight; D009687:Nuclear Proteins / Q000302:isolation & purification / Q000378:metabolism*; D010766:Phosphorylation
chemical_list: D017362:Cyclic AMP Response Element-Binding Protein; D009687:Nuclear Proteins; D000242:Cyclic AMP