2yd8

Publication Abstract from PubMed

Heparan and chondroitin sulfate proteoglycans (HSPGs and CSPGs) regulate numerous cell surface signaling events, with typically opposite effects on cell function. CSPGs inhibit nerve regeneration through receptor protein tyrosine phosphatase sigma (RPTPsigma). Here, we report that RPTPsigma acts bimodally in sensory neuron extension, mediating CSPG inhibition and HSPG growth promotion. Crystallographic analyses of a shared HSPG-CSPG binding site reveal a conformational plasticity that can accommodate diverse glycosaminoglycans with comparable affinities. Heparan sulfate and analogues induced RPTPsigma ectodomain oligomerization in solution, which chondroitin sulfate inhibited. RPTPsigma and HSPGs colocalize in puncta on sensory neurons in culture, whereas CSPGs occupy the extracellular matrix. These results lead to a model where proteoglycans can exert opposing effects on neuronal extension by competing to control the oligomerization of a common receptor.

Proteoglycan-Specific Molecular Switch for RPTP{sigma} Clustering and Neuronal Extension.,Coles CH, Shen Y, Tenney AP, Siebold C, Sutton GC, Lu W, Gallagher JT, Jones EY, Flanagan JG, Aricescu AR Science. 2011 Mar 31. PMID:21454754^[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.