title: Expression of dystroglycan and the laminin-alpha 2 chain in the rat peripheral nerve during development.
abstract: In Schwann cells, the transmembrane glycoprotein beta-dystroglycan comprises the dystroglycan complex, together with the extracellular glycoprotein alpha-dystroglycan, which binds laminin-2 (alpha 2/beta 1/gamma 1), a major component of the Schwann cell basal lamina. To provide clues to the biological functions of the interaction of the dystroglycan complex with laminin-2 in peripheral nerves, we investigated the expression of beta-dystroglycan and the laminin-alpha 2 chain in rat sciatic nerve during development by immunoblot, immunofluorescence, and immunoelectron microscopic studies. The expression of beta-dystroglycan and the laminin-alpha 2 chain in the rat sciatic nerve was low and not confined to the Schwann cell outer membrane from embryonic day 18 to birth, when there was only an immature basal lamina assembly and no compact myelin formation by Schwann cells. However, the expression of these proteins increased markedly and became clearly localized to the Schwann cell outer membrane between birth and postnatal day 7, when both basal lamina assembly and compact myelin formation by Schwann cells progressed rapidly. From postnatal day 7 to adult, there was no remarkable change in the expression of these proteins. Our results support the hypothesis that the dystroglycan complex functions as an adhesion apparatus, binding the Schwann cell outer membrane with the basal lamina, and suggest that the dystroglycan complex plays a role in Schwann cell myelination through its interaction with laminin-2.
authors.affiliation: Third Department of Internal Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Masaki
authors.forename: Kiichiro
authors.initials: K
authors.lastname: Matsumura
authors.forename: Akira
authors.initials: A
authors.lastname: Hirata
authors.forename: Hiroki
authors.initials: H
authors.lastname: Yamada
authors.forename: Asako
authors.initials: A
authors.lastname: Hase
authors.forename: Ken
authors.initials: K
authors.lastname: Arai
authors.forename: Teruo
authors.initials: T
authors.lastname: Shimizu
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yorifuji
authors.forename: Kazuo
authors.initials: K
authors.lastname: Motoyoshi
authors.forename: Keiko
authors.initials: K
authors.lastname: Kamakura
mesh_terms: D000375:Aging / Q000378:metabolism*; D000818:Animals; D003598:Cytoskeletal Proteins / Q000096:biosynthesis*; D049030:Dystroglycans; D005455:Fluorescent Antibody Technique; D015151:Immunoblotting; D007797:Laminin / Q000096:biosynthesis*; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D016253:Microscopy, Immunoelectron; D009186:Myelin Sheath / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012583:Schwann Cells / Q000166:cytology / Q000378:metabolism / Q000648:ultrastructure; D012584:Sciatic Nerve / Q000196:embryology / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D003598:Cytoskeletal Proteins; D007797:Laminin; D008562:Membrane Glycoproteins; C102645:laminin alpha 2; D049030:Dystroglycans