Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.6.4 (chondroitinase)
 2,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Midkine, a heparin-binding growth factor, plays a critical role in cell migration causing suppression of neointima formation in midkine-deficient mice. Here we have determined the molecules essential for midkine-induced migration. Midkine induced haptotaxis of osteoblast-like cells, which was abrogated by the soluble form of midkine or pleiotrophin, a midkine-homologous protein. Chondroitin sulfate B, E, chondroitinase ABC, B, and orthovanadate, an inhibitor of protein-tyrosine phosphatase, suppressed the migration. Supporting these data, the cells examined expressed PTPzeta, a receptor-type protein-tyrosine phosphatase that exhibits high affinity to both midkine and pleiotrophin and harbors chondroitin sulfate chains. Furthermore, strong synergism between midkine and platelet-derived growth factor in migration was detected. The use of specific inhibitors demonstrated that mitogen-activated protein (MAP) kinase and protein-tyrosine phosphatase were involved in midkine-induced haptotaxis but not PDGF-induced chemotaxis, whereas phosphatidylinositol 3 (PI3)-kinase and protein kinase C were involved in both functions. Midkine activated both PI3-kinase and MAP kinases, the latter activation was blocked by a PI3-kinase inhibitor. Midkine further recruited PTPzeta and PI3-kinase. These results indicate that PTPzeta and concerted signaling involving PI3-kinase and MAP kinase are required for midkine-induced migration and demonstrate for the first time the synergism between midkine and platelet-derived growth factor in cell migration.
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PMID:Haptotactic migration induced by midkine. Involvement of protein-tyrosine phosphatase zeta. Mitogen-activated protein kinase, and phosphatidylinositol 3-kinase. 1134 82