ONTOGENY OF THE CELL-ADHESION MOLECULE L1 IN THE CEREBELLUM OF WEAVERAND REELER MUTANT MICE

The ontogeny of cell adhesion molecule L1 in cerebellum was quantitati vely assessed in weaver and reeler mutant mice and in heterozygous lit ter-mate controls. In the latter the concentration and the amount of L 1 both increased from the first postnatal week to become maximum at th e second. In contrast, in the weaver and reeler neurologic mutant mice , L1 decreased steadily. The L1 concentration and the amount of L1 was lower in the cerebellum of homozygous mutant mice than in litter-mate controls. The findings are consistent with L1 being a component of ax onal plasma membranes. However, no evidence was found of any direct ef fect of the wv and rl phenotypes on L1 expression.