Changes in Fast Axonal Transport of Glycoproteins in Optic Nerves of Mice Infected With Semliki Forest Virus

Abstract

[ 3 H]fucose incorporation into mouse retinae and subsequent axonal transport of glycoproteins to optic nerve terminals was studied before and during optic nerve demyelination induced by Semliki Forest virus (SFV) infection. As was previously found for [ 3 H]proline-labelled protein, axonally transported glycoprotein was increased before demyelination. Fluorographic analysis of the increased glycoproteins and proteins, after separation by gel electrophoresis, showed particularly large increases in labelling of 2 glycoproteins (38.1 kDa and 45.0 kDa) and 3 protein (15.9 kDa, 23.8 kDa and 27.7 kDa) bands. These increases were due to host-cell rather than viral components. At the time of demyelination, however, [ 3 H]fucose incorporation into retinae of SFV-infected mice was significantly depressed, resulting in reduced label incorporation into axonally transported glycoproteins. Since glycoproteins play a role in axon-glia recognition and adhesion, the early changes in their axonal transport may contribute to the mechanism of demyelination.