Shaun Park-Snyder

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We have previously shown that bone organ cultures produce large amounts of latent transforming growth factor beta (TGF beta), which lacks latent TGF beta-binding protein (LTBP). In this study we used the known osteoblast-like cell lines UMR-106, ROS 17/2.8, and MG63 as models to further examine latent TGF beta expression in bone. We found that the(More)
Desmosomes are intercellular junctions in which cadherin cell adhesion molecules are linked to the intermediate filament (IF) system. Desmoplakin is a member of the plakin family of IF-binding proteins. The C-terminal domain of desmoplakin (DPCT) mediates binding to IFs in desmosomes. The DPCT sequence contains three regions, termed A, B and C, consisting(More)
Mannose-binding proteins (MBPs) are C-type animal lectins that recognize high mannose oligosaccharides on pathogenic cell surfaces. MBPs bind to their carbohydrate ligands by forming a series of Ca(2+) coordination and hydrogen bonds with two hydroxyl groups equivalent to the 3- and 4-OH of mannose. In this work, the determinants of the orientation of(More)
Pediatric immune thrombocytopenia (ITP) is usually self-limited. However, approximately 20% of children develop chronic ITP, which can be associated with significant morbidity because of long-term immunosuppression and splenectomy in refractory cases. To explore the molecular mechanism of chronic ITP compared with acute ITP, we studied 63 pediatric patients(More)
The mannose receptor of macrophages and liver endothelium mediates clearance of pathogenic organisms and potentially harmful glycoconjugates. The extracellular portion of the receptor includes eight C-type carbohydrate recognition domains (CRDs), of which one, CRD-4, shows detectable binding to monosaccharide ligands. We have determined the crystal(More)
C-type animal lectins are a diverse family of proteins which mediate cell-surface carbohydrate-recognition events through a conserved carbohydrate-recognition domain (CRD). Most members of this family possess a carbohydrate-binding activity that depends strictly on the binding of Ca2+ at two sites, designated 1 and 2, in the CRD. The structural transitions(More)
Resting zone and growth zone (GC) costochondral chondrocytes constitutively release latent, but not active, transforming growth factor-beta (TGF-beta) into the culture medium. When exogenous TGF-beta is added to the culture medium, no autocrine effect is observed. However, when 1,25-(OH)2D3 is added, a dose-dependent inhibition of latent TGF-beta release is(More)
The multifunctional cytokine, transforming growth factor-beta (TGF beta), is found in many tissues in a latent or inactive form. The nature and composition of the latent complex can vary depending on tissue type. The release of active TGF beta from its latent complex is a potentially important mechanism for regulation of TGF beta activity. We have shown(More)
Transforming growth factor-beta (TGF-beta) stimulates the accumulation of extracellular matrix in renal and hepatic disease. Kidney glomerular mesangial cells (GMC) and liver fat-storing cells (FSC) produce latent of inactive TGF-beta. In this study, we characterized the latent TGF-beta complexes secreted by these cells. Human FSC produce a single latent(More)
DNA sequences rich in runs of guanine have the potential to form G4 DNA, a four-stranded non-canonical DNA structure stabilized by formation and stacking of G quartets, planar arrays of four hydrogen-bonded guanines. It was reported recently that G4 DNA can be generated in Escherichia coli during transcription of plasmids containing G-rich sequences in the(More)