|
|
||||||||
Departments of Research and Medicine, Saint Francis Hospital and Medical Center, Hartford 06105; and The University of Connecticut School of Medicine, Farmington, Connecticut 06030
Osteonectin (secreted protein acidic and rich in cysteine, 40-kDa basement membrane) is a glycoprotein abundantly expressed in bone and in other tissues undergoing active remodeling. Fibroblast growth factors (FGFs) are important in skeletal development and fracture repair, events associated with extracellular matrix remodeling. We used the murine osteoblastic cell line MC3T3 to determine whether basic FGF (bFGF) regulates osteonectin expression in bone. Northern blot analysis showed that bFGF decreased osteonectin transcripts in a dose- and time-dependent manner. This regulation was independent of the mitogenic effect of bFGF but was dependent on new protein synthesis. Immunoprecipitation of [35S]methionine-cysteine osteoblast-conditioned medium and cell layer proteins showed that bFGF decreased osteonectin synthesis. Nuclear runoff assays failed to reveal regulation of osteonectin gene transcription by bFGF. However, bFGF dramatically decreased the stability of osteonectin mRNA in transcriptionally arrested osteoblasts. This destabilization of osteonectin mRNA may be one means by which bFGF regulates extracellular matrix remodeling.
secreted protein acidic and rich in cysteine; extracellular matrix; growth factors; bone; 40-kDa basement membrane protein
This article has been cited by other articles:
![]() |
A. M. Delany and E. Canalis Dual Regulation of Stromelysin-3 by Fibroblast Growth Factor-2 in Murine Osteoblasts J. Biol. Chem., June 26, 1998; 273(26): 16595 - 16600. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |