Temporal and functional changes in glycosaminoglycan expression during osteogenesis.
Heparan sulfate proteoglycans (HSPGs) are complex and labile macromolecular moieties on the surfaces of cells that control the activities of a range of extracellular proteins, particularly those driving growth and regeneration. Here, we examine the biosynthesis of heparan sulfate (HS) sugars produced by cultured MC3T3-E1 mouse calvarial pre-osteoblast cells in order to explore the idea that changes in HS activity in turn drive phenotypic development during osteogenesis. Cells grown for 5 days under proliferating conditions were compared to cells grown for 20 days under mineralizing conditions with respect to their phenotype, the forms of HS core protein produced, and their HS sulfotransferase biosynthetic enzyme levels. RQ-PCR data was supported by the results from the purification of day 5 and day 20 HS forms by anionic exchange chromatography. The data show that cells in active growth phases produce more complex forms of sugar than cells that have become relatively quiescent during active mineralization, and that these in turn can differentially influence rates of cell growth when added exogenously back to preosteoblasts.
Stem Cell and Tissue Repair Group, Institute of Molecular and Cell Biology, Proteos, Singapore, Singapore. vnurcombe@imcb.a-star.edu.sg
Victor
V
Nurcombe
Fuqi Jack
FJ
Goh
Larisa M
LM
Haupt
Sadasivam
S
Murali
Simon M
SM
Cool
D016475:3T3 Cells; D000818:Animals; D002113:Calcification, Physiologic / Q000235:genetics / Q000502:physiology; D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D049109:Cell Proliferation / Q000187:drug effects; D005109:Extracellular Matrix / Q000187:drug effects / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D005966:Glucuronidase / Q000235:genetics / Q000378:metabolism; D006025:Glycosaminoglycans / Q000378:metabolism*; D019812:Heparan Sulfate Proteoglycans / Q000235:genetics / Q000378:metabolism; D006497:Heparan Sulfate / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D015151:Immunoblotting; D051379:Mice; D010012:Osteogenesis / Q000235:genetics / Q000502:physiology*; D010641:Phenotype; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015238:Sulfotransferases / Q000235:genetics / Q000378:metabolism*; D000099175:Heparanase
D005966:Glucuronidase; D006025:Glycosaminoglycans; D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate; D015238:Sulfotransferases; D000099175:Heparanase