α-Dystroglycan was quantitatively enriched from mammalian brain based on its uniform reactivity with Vicia villosa agglutinin and resolved into sub-populations possessing or lacking the sulfated glucuronic acid epitope recognized by monoclonal antibody HNK-1. We generated a new monoclonal antibody specific for a glycoepitope on brain α-dystroglycan but absent from α-dystroglycan expressed in all other tissues examined. Finally, we found that laminin-10/11 preferentially bound to brain α-dystroglycan compared to skeletal muscle α-dystroglycan. Our results suggest that tissue-specific glycosylation modifies the laminin binding specificity of α-dystroglycan.
Bibliographical noteFunding Information:
We thank Dr. Hynda Kleinman for laminin-1 and Mr. Travis Suss for technical assistance. Supported by the UW Medical School under the HHMI Research Resources Program for Medical Schools, the MDA, and NIH Grant ARO1985 to J.M.E. and a Predoctoral Fellowship from the Northland Affiliate of the AHA to E.L.M.
- Oligosaccharide structure