Dermatan sulfate and de-sulfated heparin solubilized collagen-tailed acetylcholinesterase from the rat neuromuscular junction.

We are interested in the study of the interactions involved in the attachment of collagen-tailed acetylcholinesterase (AChE) to the synaptic basal lamina. The fact that AChE occupies less than 0.1% of the muscle basal lamina, suggests that there is a very high specificity in the interaction that defines its distribution. We have previously found that asymmetric AChE is bound to the neuromuscular junction via heparan sulfate proteoglycans. Sulfated glycosaminoglycans as heparan sulfate and heparin extracted the asymmetric AChE from the synaptic basal lamina. Here we show that dermatan sulfate as well as de-sulfated heparin, are also able to extract collagen-tailed AChE. Taking into account that the solubilization of the asymmetric AChE is concomitant with the liberation of a dermatan sulfate proteoglycan from the rat neuromuscular junction, the present results open the possibility that the collagen-tailed AChE is also anchored to dermatan sulfate proteoglycans at the synaptic basal lamina.