In prior work we showed that a metallogelatinase is secreted from @entity235 @entity9600 cells and directly activated by exocytosed mast cell @entity70063 . The current work identifies the protease as a @entity235 homologue of progelatinase B (92-kDa gelatinase, @entity11799 ), determines the sites cleaved by @entity70063 , and explores the regulation of gelatinase expression in @entity9600 cells. To obtain a cDNA encoding the complete sequence of @entity9600 @entity11799 , a 2. 3-kilobase clone encoding progelatinase was isolated from a BR @entity9600 library. The sequenced cDNA predicts a 704- @entity3689 protein 80% identical to @entity1 progelatinase B. Regions thought to be critical for active site latency, such as the @entity2569 -containing propeptide sequence, PRCGVPD, and the catalytic domain sequence, HEFGHALGLDHSS, are entirely conserved. Cleavage of progelatinase B by purified @entity235 @entity70063 yielded an approximately 84-kDa product that contained two @entity2733 -terminal @entity3689 sequences, QTFEGDLKXH and EGDLKXHHND, which correspond to residues 89-98 and 92-101 of the cDNA predicted sequence, respectively. Thus, @entity70063 cleaves the catalytic domain of @entity11799 at the @entity815 88- @entity7647 89 and @entity815 91- @entity367 92 bonds. Like BR cells, the C2 line of @entity235 @entity9600 cells constitutively secrete progelatinase B which is activated by @entity70063 . By contrast, non-chymase-producing C1 cells secrete a @entity11799 (which remains in its proform) only in response to @entity4514 . Whereas @entity4514 stimulation of BR cells produced a approximately 15-fold increase in @entity11799 mRNA expression, @entity619 down-regulated its expression by approximately 5-fold. Thus, extracellular stimuli may regulate the amount of mast cell progelatinase B expressed by mast cells. These data further support a role for mast cell @entity70063 in tissue remodeling involving @entity11799 -mediated degradation of matrix proteins.

@entity235 mast cell XXXX activates progelatinase B by cleaving the @entity815 88- @entity7647 89 and @entity815 91- @entity367 92 bonds of the catalytic domain.

@entity1 :: ('9606', 'Species') :: ['human'] @entity9600 :: ('MESH:D034801', 'Disease') :: ['mastocytoma'] @entity4514 :: ('MESH:D013755', 'Chemical') :: ['12-O-tetradecanoylphorbol-13-acetate'] @entity235 :: ('9615', 'Species') :: ['canine', 'dog'] @entity2569 :: ('CHEBI:17561', 'Chemical') :: ['Cys'] @entity2733 :: ('CHEBI:29345', 'Chemical') :: ['NH2'] @entity7647 :: ('CHEBI:32668', 'Chemical') :: ['Gln'] @entity11799 :: ('403885(Tax:9615)', 'Gene') :: ['MMP-9', 'gelatinase B'] @entity619 :: ('MESH:D003907', 'Chemical') :: ['dexamethasone'] @entity367 :: ('CHEBI:18237', 'Chemical') :: ['Glu'] @entity815 :: ('CHEBI:28044', 'Chemical') :: ['Phe'] @entity3689 :: ('D000596', 'Chemical') :: ['amino acid'] @entity70063 :: ('490628(Tax:9615)', 'Gene') :: ['alpha-chymase']
@entity70063 :: (490628(Tax:9615),Gene) :: ['alpha-chymase']
