Inhibition of myeloid differentiation by the helix-loop-helix protein Id.
Id is a helix-loop-helix (HLH) protein that represses activity of several basic helix-loop-helix (bHLH) proteins involved in cell type--specific transcription and cell lineage commitment. The myeloid precursor cell line 32DC13(G) expressed Id messenger RNA, which was transiently decreased when cells were induced to terminally differentiate with granulocyte--colony-stimulating factor. Concomitant with the decrease of Id messenger RNA was the appearance in nuclear extracts of DNA binding proteins that recognized a canonical E-box motif, a DNA binding site for some bHLH proteins. Constitutive expression of an Id complementary DNA in 32DC13(G) cells blocked their ability to differentiate and to induce E-box-binding activity. These results suggest that Id and, hence, bHLH proteins function in the process of myeloid differentiation.
Wistar Institute of Anatomy and Biology, Philadelphia, PA 19104.
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Kreider
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Benezra
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Rovera
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Kadesch
D002454:Cell Differentiation / Q000187:drug effects*; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000502:physiology*; D015870:Gene Expression; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology; D006410:Hematopoiesis / Q000187:drug effects*; D066298:In Vitro Techniques; D051798:Inhibitor of Differentiation Protein 1; D007377:Interleukin-3 / Q000494:pharmacology; D046911:Macromolecular Substances; D012333:RNA, Messenger / Q000235:genetics; D012097:Repressor Proteins; D014157:Transcription Factors
D004268:DNA-Binding Proteins; D051798:Inhibitor of Differentiation Protein 1; D007377:Interleukin-3; D046911:Macromolecular Substances; D012333:RNA, Messenger; D012097:Repressor Proteins; D014157:Transcription Factors; D016179:Granulocyte Colony-Stimulating Factor