Identify changes in gene expression during overexpression of the glycosyltransferase LARGE

alpha-dystroglycan is a component of the dystrophin associated glycoprotein complex that binds components of the extracellular matrix (including laminin, perlecan and neurexin) via its carbohydrate groups. Recently, a group of muscular dystrophies have been identified due to the aberrant glycosylation of this molecule (dystroglycanopathies). The overexpression of the glycosyltransferase LARGE in several cell lines results in alpha-dystroglycan hyperglycosylation and enhanced ligand binding. The glycan structures induced by LARGE overexpression are unknown. We have injected into mouse legs two LARGE constructs, one wild type and the second in which a DxD motif has been mutated to NNN as a control. We aim to identify genes unregulated during LARGE induced hyperglycosylation in order to gain insight into the enzymes involved in this process and ultimatley the nature of the glycans responsible for ligand binding. RNA preparations from two LARGE constructs, were sent to Microarray Core (E). One wild type and the second in which a DxD motif has been mutated to NNN as a control. The aim is to identify genes unregulated during LARGE induced hyperglycosylation in order to gain insight into the enzymes involved in this process and ultimatley the nature of the glycans responsible for ligand binding. The RNA was amplified, labeled, and hybridized to teh GLYCOv3 microarrays.