Myelination in the absence of myelin-associated glycoprotein

THE hypothesis that myelin-associated glycoprotein (MAG) initiates myelin formation is based in part on observations that MAG has an adhesive role in interactions between oligodendrocytes and neurons1. Furthermore, the over- or underexpression of MAG in transfected Schwann cells in vitro leads to accelerated myelination2 or hypomyelination3, respectively. Here we test this idea by creating a null mutation in the mag locus and deriving mice that …