Matrix Gla protein is differentially expressed during the deposition of a calcified matrix by vascular pericytes.
PCR-based subtractive hybridisation was used to identify genes up-regulated when pericytes undergo osteogenic differentiation and deposit a calcified matrix. cDNA pools were generated from confluent pericytes and from pericyte cultures containing calcified nodules. A pericyte cDNA library was screened with the product of the subtraction procedure (calcified minus confluent cDNA) and the majority of the positive clones were identified as matrix Gla protein (MGP). Northern analysis and immunohistochemistry demonstrated that MGP was only expressed by pericytes in calcified nodules. Antibodies to MGP inhibited the deposition of a calcified matrix by pericytes, suggesting that MGP regulates both cell differentiation and calcification.
Canfield
A E
AE
Wellcome Trust Centre for Cell-Matrix Research, School of Medicine, University of Manchester, Manchester, UK. ann.canfield@man.ac.uk
Doherty
M J
MJ
Kelly
V
V
Newman
B
B
Farrington
C
C
Grant
M E
ME
Boot-Handford
R P
RP
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies; D002113:Calcification, Physiologic; D002135:Calcium-Binding Proteins / Q000032:analysis / Q000235:genetics* / Q000378:metabolism; D002417:Cattle; D002454:Cell Differentiation; D002478:Cells, Cultured; D016326:Extracellular Matrix Proteins; D015723:Gene Library; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000276:immunology; D020286:Pericytes / Q000166:cytology / Q000502:physiology*; D012171:Retinal Vessels / Q000166:cytology / Q000502:physiology; D000097568:Matrix Gla Protein
D000906:Antibodies; D002135:Calcium-Binding Proteins; D016326:Extracellular Matrix Proteins; D010446:Peptide Fragments; D000097568:Matrix Gla Protein