Differential Ultrastructural Localization of Myelin Basic Protein, Myelin/Oligodendroglial Glycoprotein, and 2′,3′‐Cyclic Nucleotide 3′‐Phosphodiesterase in the CNS of Adult Rats

Abstract

In a light and electron microscopic immunocytochemical study we have examined the distribution of myelin basic protein (MBP), 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP), and myelin/oligodendroglial glycoprotein (MOG) within CNS myelin sheaths and oligodendrocytes of adult Sprague-Dawley rats. Ultrastructural immunocytochemistry allowed quantitative analysis of antigen density in different myelin and oligodendrocyte zones: MBP was detectable in high density over the whole myelin sheath, but not in regions of loops, somata, or the oligodendrocyte plasma membrane. CNP reactivity was highest at the myelin/axon interface, and found in lower concentration over the outer lamellae of myelin sheaths, at the cytoplasmic face of oligodendrocyte membranes, and throughout the compact myelin. MOG was preferentially detected at the extracellular surface of myelin sheaths and oligodendrocytes and in only low amounts in the lamellae of compacted myelin and the myelin/axon border zone. Our studies, thus, indicate further the presence of different molecular domains in compact myelin, which may be functionally relevant for the integrity and maintenance of the myelin sheath.

Development of Myelin Oligodendrocyte Glycoprotein Autoreactive Transgenic B Lymphocytes: Receptor Editing In Vivo After Encounter of a Self-Antigen Distinct from Myelin Oligodendrocyte Glycoprotein

“…Second, MOG has several properties setting it apart from other myelin proteins. It is exclusively localized on the outer surface of the myelin sheath, where it can be readily attacked by specific Ab mediating demyelination (5,6). In addition, the expression of MOG is restricted to the CNS, and it appears late during development of myelin (7)(8)(9)(10)(11).…”

Myelin matters: proteomic insights into white matter disorders

“…MOG is an Ig-CAM mainly localized in the abaxonal myelin subcompartment (Figure 1) [46,47], but its function has remained unknown, mainly because no histological abnormalities have been reported for mice lacking MOG [48]. Interestingly, MOG-directed antibodies can have a direct influence on oligodendrocytes, at least in vitro.…”

The myelin oligodendrocyte glycoprotein directly binds nerve growth factor to modulate central axon circuitry

“…Although the major protein components of central nervous system (CNS) myelin consist of myelin basic protein (MBP), myelin associated glycoprotein, and the proteolipid protein, myelin oligodendrocyte glycoprotein (MOG), a minor component of myelin, is the only protein exclusively restricted to the outermost lamellae of compact CNS myelin (Brunner et al, 1989). In order for a myelin protein to display binding capacity, we further hypothesized that it must share structural features with TrkA.…”