Journal of Neurochemistry Lippincott—Raven Publishers, Philadelphia © 1997 International Society for Neurochemistry Functional Analysis of the Mouse Myelin/Oligodendrocyte Glycoprotein Gene Promoter in the Oligodendroglial CG4 Cell Line S. K. Solly, *~• Daubas, M. Monge, *A. Dautigny, and B. Zaic Laboratoire de Neurohiologie Celiulaire, Moldculaire et Clinique, INSERM U. 134, Hôpital de Ia Salpêtrière, Université Pierre et Marie Curie; and *J,~lboratoirede Neurogénétique Moléculaire, CNRS URA 1488, Inst itut des Neurosciences, Université Pierre et Marie Curie, Paris, France Abstract: Myelin/oligodendrocyte glycoprotein (MOG) is a late phylogenetic acquisition among vertebrates that is found only in mammals. MOG is a minor component of myelin protein, representing ‘—‘0.01 —0.05% of the total. Regulatory elements in the MOG gene were identified by transfecting the oligodendroglial CG4 cell line with chimeric MOG—luciferase genes. Only a few hundred base pairs upstream of the coding sequence were neces- sary for high-level activity of the mouse MOG promoter. More distal recognition sites may exist, because silencing activity, indicative of negative regulatory elements, was detected upstream of base pair 657. Transcriptional ac- tivity of chimeric MOG— and myelin basic protein—lucifer- ase genes was greater in CG4 cells than in 3T3 fibroblasts or C6 gliob!astoma, demonstrating their superiority for functional analysis of myelin gene regulatory elements. Key Words: Myelin—Oligodendrocyte—Myelin basic protein—Transcriptional regulation —Tissue-specific ex- pression. J. Neurochem. 68, 1705—1711 (1997). Myelin, a membranous structure that wraps around axons, facilitating rapid nerve conduction, is synthe- sized by oligodendrocytes in the CNS. Myelin/oligo- dendrocyte glycoprotein (MOG) was first identified with a mouse monoclonal antibody, 8-18C5, raised against rat cerebellar glycoproteins (Linington et al., 1984). MOG represents only ‘—‘0.01—0.05% of all my- elm proteins (Amiguet et al., 1992) and is a late evolu- tionary acquisition found in the mammals but not in fish or birds (Birling et al., 1993). The cDNA encoding MOG was initially isolated from rat (Gardinier et al., 1992) and, subsequently, bovine, mouse, and human (Pham-Dinh et al., 1993, 1994; Hilton et al., 1995) myelin. The deduced amino acid sequence suggests that MOG belongs to the immunoglobulin superfamily. The MOG mouse and human genes have been isolated and are composed of eight exons in both species (Dau- bas et al., 1994; Hilton et al., 1995; Pham-Dinh et al., 1995; Roth et al., 1995). The developmental pattern of MOG mRNA expression has been studied in the rat (Pham-Dinh et al., 1993) and the mouse (Solly et a!., 1996). Several groups have shown that a cell-mediated autoimmune response to MOG might play a role in the initiation or progression of multiple sclerosis (Lin- ington and Lassmann, 1987; Kerlero de Rosbo et al., 1993). The formation, assembly, and maintenance of the myelin sheath require complex and coordinate control during development. The recent isolation and charac- terization of promoter regions of several genes encod- ing myelin proteins indicate that DNA sequences nec- essary for cell type-specific expression are located within the 5’ flanking regions (reviewed by Hudson et al., 1995). Experiments involving transfection of cultured cells or transcription in vitro showed that both ubiquitous and specific cis-acting elements in these regions interact with nuclear factors present in oligo- dendrocytes to regulate myelin gene transcription. An oligodendroglial cell line that transcribes all the myelin genes should serve both as an in vitro system for char- acterizing cis-regulatory elements in these genes and Received September 23, 1996; revised manuscript received No- vember 26, 1996; accepted December 3, 1996. Address correspondence and reprint requests to Dr. B. Zaic at Laboratoire de Neurobiologie Cellulaire, Moléculaire et Clinique, INSERM U. 134, Hôpital de Ia Salpëtrière, 75651, Paris Cedex 13, France. The present address of Dr. P. Daubas is Unite de GCnétique Moléc- ulaire du Développement, Institut Pasteur, 25-28 rue du Docteur Roux, 75015 Paris, France. Abbreviations used: CMV, cytomegalovirus; CNP, 2’ ,3 ‘-cyclic nucleotide phosphodiesterase; GTX, glial- and testis-specific homeo- box gene; MAG, myelin-associated glycoprotein; MBP, myelin basic protein; MOG, myelin/oligodendrocyte glycoprotein; MSV, Mob- ney murine sarcoma virus; MyEF-2, myelin gene expression factor- 2; P0, protein 0; PEI, polyethylenimine; PLP, proteolipid pro- tein; SCIP, suppressed cyclic AMP-inducible protein; SV, simian virus 40. The 3,800 nucleotide sequence of the mouse MOG promoter re- gion reported in this article will appear in the EMBL, GenBank, and DDBJ Nucleotide Sequence Databases under accession no. Y08231. 1705