Composition of myelin proteins in murine genetic myelin dysgenesis: the quaking mutant.

Abstract

SummaryMyelin was isolated by sucrose density-gradient centrifugation from brains of Quaking mutants and littermate controls at the developmental ages of most active myelination. The myelin proteins were solubilized in sodium dodecyl sulfate (SDS) and separated by electrophoresis in SDS-poly-acrylamide gels. The yield of myelin from the Quaking mutant at ages varying from 3 weeks to 3 months postpartum was constant and did not show the progressive increase found in normal brain. There was a marked reduction of proteolipid and lesser decrease of basic protein in the myelin subfraction from the Quaking mutant. The proportion of high molecular-weight (Wolf-gram) proteins of the Quaking mutant was increased though a consistent diminution of one of these was observed. Alteration or deficient synthesis of a myelin protein could be the primary genetic error in the dysmyelination manifest by this mutant.This study was supported by USPHS Grant NB-06926. M. J. D. was a predoctoral trainee in Biochemistry supported ...