Axonal Swellings and Degeneration in Mice Lacking the Major Proteolipid of Myelin
Author:
Griffiths Ian123, Klugmann Matthias123, Anderson Thomas123, Yool Donald123, Thomson Christine123, Schwab Markus H.123, Schneider Armin123, Zimmermann Frank123, McCulloch Mailise123, Nadon Nancy123, Nave Klaus-Armin123
Affiliation:
1. I. Griffiths, T. Anderson, D. Yool, C. Thomson, M. McCulloch, Applied Neurobiology Group, Department of Veterinary Clinical Studies, University of Glasgow, Glasgow G61 1QH, Scotland, UK. 2. M. Klugmann, M. H. Schwab, A. Schneider, F. Zimmerman, K.-A. Nave, Zentrum für Molekulare Biologie (ZMBH), Universität Heidelberg, Im Neuenheimer Feld 282, D-69120 Heidelberg, Germany. 3. N. Nadon, Oklahoma Medical Research Foundation, 825 Northeast 13th Street, Oklahoma City, OK 73104, USA.
Abstract
Glial cells produce myelin and contribute to axonal morphology in the nervous system. Two myelin membrane proteolipids, PLP and DM20, were shown to be essential for the integrity of myelinated axons. In the absence of PLP-DM20, mice assembled compact myelin sheaths but subsequently developed widespread axonal swellings and degeneration, associated predominantly with small-caliber nerve fibers. Similar swellings were absent in dysmyelinated
shiverer
mice, which lack myelin basic protein (MBP), but recurred in MBP*PLP double mutants. Thus, fiber degeneration, which was probably secondary to impaired axonal transport, could indicate that myelinated axons require local oligodendroglial support.
Publisher
American Association for the Advancement of Science (AAAS)
Subject
Multidisciplinary
Reference22 articles.
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