Glial hyaluronate-binding protein in dysmyelinating mice mutants: jimpy, quaking and shiverer.

Cryostat sections of cerebral hemispheres, cerebellum and spinal cord from dysmyelinating mice mutants (quaking, jimpy and shiverer) and littermate controls were stained by indirect immunofluorescence with polyclonal antibodies to the glial hyaluronate-binding protein (GHAP), a brain-specific extracellular matrix glycoprotein produced by astrocytes. In normal mice, the distribution of GHAP was similar to that previously reported in human, calf, pig and dog. The antigen was mainly localized in white matter, the granular layer of the cerebellum being the main exception. No differences were observed between mutants and littermate controls, except that with both GHAP and glial fibrillary acidic protein antibodies the glial framework was denser in the mutants, probably due to the reduction in myelin. The findings suggest that GHAP expression by astrocytes is not induced by myelination and that white matter astrocytes constitute a distinct glial population.