title: LINGO-1-mediated inhibition of oligodendrocyte differentiation does not require the leucine-rich repeats and is reversed by p75(NTR) antagonists.
abstract: LINGO-1 is a potent negative regulator of oligodendrocyte differentiation and hence may play a pivotal restrictive role during remyelination in demyelinating diseases such as multiple sclerosis. However, little is known as to which stages of oligodendrocyte differentiation are inhibited by LINGO-1, which domains of the protein are involved and whether accessory proteins are required. Here, we show that LINGO-1 expression in the human oligodendroglial cell line MO3.13 inhibited process extension and this was reversed by an anti-LINGO-1 antibody or the antagonist LINGO-1-Fc. LINGO-1 expression was also found to inhibit myelin basic protein transcription in the rat oligodendroglial cell line CG4. Both of these inhibitory actions of LINGO-1 were abrogated by deletion of the entire ectodomain or cytoplasmic domains but, surprisingly, were unaffected by deletion of the leucine-rich repeats (LRRs). As in neurons, LINGO-1 physically associated with endogenous p75(NTR) in MO3.13 cells and, correspondingly, its inhibition of process extension was reversed by antagonists of p75(NTR). Thus, LINGO-1 inhibits multiple aspects of oligodendrocyte differentiation independently of the LRRs via a process that requires p75(NTR) signalling.
authors.affiliation: Novartis Institutes for Biomedical Research, Basel, Switzerland.
authors.forename: Dimitris
authors.initials: D
authors.lastname: Bourikas
authors.forename: Anis
authors.initials: A
authors.lastname: Mir
authors.forename: Adrian Robert
authors.initials: AR
authors.lastname: Walmsley
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002454:Cell Differentiation / Q000502:physiology*; D002460:Cell Line; D002469:Cell Separation; D005434:Flow Cytometry; D006801:Humans; D047468:Immunoprecipitation; D008565:Membrane Proteins / Q000378:metabolism*; D004676:Myelin Basic Protein / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D009836:Oligodendroglia / Q000166:cytology* / Q000378:metabolism*; D051381:Rats; D020800:Receptor, Nerve Growth Factor / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic
chemical_list: C482293:LINGO1 protein, human; C525164:LINGO1 protein, rat; D008565:Membrane Proteins; D004676:Myelin Basic Protein; D009419:Nerve Tissue Proteins; D020800:Receptor, Nerve Growth Factor