Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.21.9 (enterokinase)
 675 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Osteopontin (OPN) is a secreted phosphoprotein shown to function in wound healing, inflammation, and tumor progression. Expression of OPN is often co-localized with members of the matrix metalloproteinase (MMP) family. We report that OPN is a novel substrate for two MMPs, MMP-3 (stromelysin-1) and MMP-7 (matrilysin). Three cleavage sites were identified for MMP-3 in human OPN, and two of those sites were also cleaved by MMP-7. These include hydrolysis of the human Gly166-Leu167, Ala201-Tyr202 (MMP-3 only), and Asp210-Leu211 peptide bonds. Only the N-terminal Gly-Leu cleavage site is conserved in rat OPN (Gly151-Leu152). These sites are distinct from previously reported cleavage sites in OPN for the proteases thrombin or enterokinase. We found evidence for the predicted MMP cleavage fragments of OPN in vitro in tumor cell lines, and in vivo in remodeling tissues such as the postpartum uterus, where OPN and MMPs are co-expressed. Furthermore, cleavage of OPN by MMP-3 or MMP-7 potentiated the function of OPN as an adhesive and migratory stimulus in vitro through cell surface integrins. We predict that interaction of MMPs with OPN at tumor and wound healing sites in vivo may be a mechanism of regulation of OPN bioactivity.
 ...
PMID:Osteopontin, a novel substrate for matrix metalloproteinase-3 (stromelysin-1) and matrix metalloproteinase-7 (matrilysin). 1137 93

The nucleoprotein (N) and the phosphoprotein (P) of the human respiratory syncytial virus (HRSV), A2 strain, were cloned into pMAL-c2e vector. The proteins were expressed fused with the maltose-binding protein (MBP) and were preferentially found in the soluble fraction of the bacterial lysate. After their purification using amylose resin, almost no other protein was detected in SDS-PAGE. The fused proteins were cleaved by digestion with enterokinase and then used as antigens for BALB/c mice immunization. The obtained polyclonal antibodies were tested against HRSV infected cells in immunofluorescence assays. The results indicate that the antibodies generated against the recombinant proteins were able to recognize the virus proteins. We now intend to purify the cleaved N and P proteins and use them in structural studies. The recombinant proteins will also be tested as potential inducers of a protective immunity against the HRSV.
 ...
PMID:Production of polyclonal antibodies against the human respiratory syncytial virus nucleoprotein and phosphoprotein expressed in Escherichia coli. 1729 25