A role for the helix-loop-helix protein Id2 in the control of oligodendrocyte development.
Compared to neurons, the intracellular mechanisms that control glial differentiation are still poorly understood. We show here that oligodendrocyte lineage cells express the helix-loop-helix proteins Mash1 and Id2. Although Mash1 has been found to regulate neuronal development, we found that in the absence of Mash1 oligodendrocyte differentiation occurs normally. In contrast, we found that overexpression of Id2 powerfully inhibits oligodendrocyte differentiation, that Id2 normally translocates out of the nucleus at the onset of differentiation, and that absence of Id2 induces premature oligodendrocyte differentiation in vitro. These findings demonstrate that Id2 is a component of the intracellular mechanism that times oligodendrocyte differentiation and point to the existence of an as yet unidentified MyoD-like bHLH protein necessary for oligodendrocyte differentiation.
Wang
S
S
Stanford University School of Medicine, Department of Neurobiology, Sherman Fairchild Science Building D231, 299 Campus Drive, Stanford, CA 94305, USA.
Sdrulla
A
A
Johnson
J E
JE
Yokota
Y
Y
Barres
B A
BA
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins; D002454:Cell Differentiation; D002455:Cell Division; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000032:analysis / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D015870:Gene Expression; D018257:Helix-Loop-Helix Motifs; D007150:Immunohistochemistry; D051797:Inhibitor of Differentiation Protein 2; D051379:Mice; D018345:Mice, Knockout; D009836:Oligodendroglia / Q000737:chemistry / Q000166:cytology* / Q000378:metabolism; D009900:Optic Nerve / Q000166:cytology; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D012097:Repressor Proteins; D013234:Stem Cells / Q000737:chemistry / Q000166:cytology* / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors / Q000032:analysis / Q000172:deficiency / Q000502:physiology; D014284:Triiodothyronine / Q000494:pharmacology
D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D051797:Inhibitor of Differentiation Protein 2; D010982:Platelet-Derived Growth Factor; D012333:RNA, Messenger; D012097:Repressor Proteins; D014157:Transcription Factors; D014284:Triiodothyronine; C499317:Ascl1 protein, mouse; C499318:Ascl1 protein, rat; C497451:Id2 protein, rat; C497452:Idb2 protein, mouse