Thermodynamic and structural studies of carbohydrate binding by the agrin-G3 domain.

ABSTRACT: Agrin is a key heparan sulfate proteoglycan involved in the development and maintenance of synaptic junctions between nerves and muscles. Agrin's important functions include clustering acetylcholine receptors on the postsynaptic membranes of muscles and binding to the muscle protein alpha-dystroglycan through its glycan chains. ITC and NMR were used to study the interactions of the C-terminal domain, agrin-G3, with carbohydrates implicated in agrin's functions. Sialic acid caps the glycan chains of alpha-dystroglycan and occurs as a posttranslational modification on the muscle-specific kinase component of the agrin receptor. We found that agrin-G3 binds sialic acid in a Ca2+-dependent manner. ITC data indicate that binding is exothermic and occurs with a 1:1 stoichiometry. NMR chemical shi

SUBMITTER: Sallum CO 

PROVIDER: S-EPMC2111043 | biostudies-literature | 2007 Aug

REPOSITORIES: biostudies-literature