Vimentin in the central nervous system. A study of the mesenchymal-type intermediate filament-protein in Wallerian degeneration and in postnatal rat development by two-dimensional gel electrophoresis.

Intermediate filament proteins were identified by two-dimensional gel electrophoresis in urea extracts of rat optic nerves undergoing Wallerian degeneration and in cytoskeletal preparations of rat brain and spinal cord during postnatal development. The glial fibrillary acidic (GFA) protein and vimentin were the major optic nerve proteins following Wallerian degeneration. Vimentin was a major cytoskeletal component of newborn central nervous system (CNS) and then progressively decreased until it became barely identifiable in mature brain and spinal cord. The decrease of vimentin occurred concomitantly with an increase in GFA protein. A protein with the apparent molecular weight of 61,000 and isoelectric point of 5.6 was identified in both cytoskeletal preparations of brain and spinal cord, and in urea extracts of normal optic nerves. The protein disappeared together with the polypeptides forming the neurofilament triplet in degenerated optic nerves.