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

Proteoglycans appear to play an important role in modulating cell-cell and cell-matrix interactions during nervous tissue histogenesis. The nervous tissue-specific chondroitin sulfate proteoglycans neurocan and phosphacan/protein-tyrosine phosphatase-zeta/beta were found to be high-affinity ligands of the neural cell adhesion molecule TAG-1/axonin-1, with dissociation constants of 0.3 nM and 0.04 nM, respectively. Phosphacan binding was decreased by approximately 70% following chondroitinase treatment, whereas binding of neurocan was not affected. The contribution of chondroitin sulfate chains to the binding of neurocan and phosphacan to TAG-1/axonin-1 is therefore the opposite of that previously observed for their binding to two other Ig-superfamily neural cell adhesion molecules, Ng-CAM/L1 and N-CAM. Moreover, whereas phosphacan interactions with certain proteins are mediated at least in part by N-linked oligosaccharides on the proteoglycan, N-deglycosylation of phosphacan had no effect on its binding to TAG-1/axonin-1. In addition to the chondroitin sulfate proteoglycans described above, we have demonstrated that N-CAM is a high-affinity ligand of TAG-1/axonin-1 (Kd approximately 1 nM), and specific binding of TAG-1/axonin-1 to tenascin-C was also observed (Kd approximately 9 nM). Immunocytochemical studies of embryonic and early postnatal nervous tissue showed an overlapping localization of TAG-1/axonin-1 with all four of these ligands, further supporting the biological significance of their ability to interact in vitro.
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PMID:TAG-1/axonin-1 is a high-affinity ligand of neurocan, phosphacan/protein-tyrosine phosphatase-zeta/beta, and N-CAM. 866 15

During the initial stages of development, the notochord provides repulsive signals for dorsal root ganglion (DRG) axons via semaphorin 3A/neuropilin-1, axonin-1/SC2, and other unknown repulsive molecules. The notochord is known to produce aggrecan, one of the chondroitin sulfate proteoglycans (CSPGs). We report here that adding aggrecan to the culture medium cannot only induce DRG growth cone collapse, but also inhibit DRG axonal growth. Using cocultures composed of tissues derived from chick embryos or neuropilin-1-deficient mice treated with chondroitinase ABC, we show the direct evidence that CSPGs are involved in notochord-derived repulsion for DRG axons. At later developmental stages, CSPGs are involved in perinotochordal sheath-derived axon repulsion, but not in notochord core-derived repulsion. We further demonstrate that TAG-1/axonin-1/SC2 is not involved in mediating repulsive activities by CSPGs, but is required for notochord core-derived axon repulsion. Thus, notochord-derived multiple axon repulsions act in a spatiotemporal-specific manner to shape the initial trajectories of DRG axons.
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PMID:Developmental regulation of notochord-derived repulsion for dorsal root ganglion axons. 1501 39