Divergent fates of von Willebrand factor and its propolypeptide (von Willebrand antigen II) after secretion from endothelial cells.

摘要: Abstract The intracellular site of cleavage pro-von Willebrand factor subunit and the subsequent fate propolypeptide (von antigen II) mature von (vWf) were investigated. Both propolypeptide, which was found to be a homodimer noncovalently linked subunits, vWf released from Weibel-Palade bodies endothelial cells following stimulation with secretagogues. The stoichiometry two proteins essentially equimolar. This indicates that packaged into as one unit, pro-vWf, proteolytic pro-vWf is likely post-Golgi event. association prosequences dimers supports their hypothetical role in multimerization process. After secretion, distributed differently, based on observations. did not associate culture medium, codistribute extracellular "patches release" stimulated cells, detected cell matrix, contain vWf. Additionally, contrast vWf, bind matrix human foreskin fibroblasts. Since does interact matrices vitro, it highly unlikely would promote platelet adhesion subendothelium vivo.