A Stat1alpha factor regulates the expression of the human vimentin gene by IFN-gamma.
Vimentin is an intermediate filament protein normally expressed in cells of mesenchymal origin. Here, we report an increase in vimentin gene transcription induced by the cytokine interferon-y (IFN-gamma). Northern blot analysis and reporter gene assays reveal that IFN-gamma induces vimentin gene transcription in HeLa cells. However, no increase in vimentin mRNA synthesis was observed de novo in MCF-7 cells, which do not already express vimentin. Band shift analysis shows that the Stat1alpha protein mediates vimentin induction by IFN-gamma. A human mutant fibroblast cell line (U3A), which lacks Stat1alpha but expresses vimentin mRNA, yields no increase in vimentin mRNA levels on the addition of IFN-gamma. These results suggest that the induction of vimentin gene expression might be an important part of a complex cellular response to IFN-gamma.
Izmailova
E S
ES
Department of Biochemistry and Molecular Biophysics, Massey Cancer Center, Medical College of Virginia Campus/Virginia Commonwealth University, Richmond 23298, USA.
Snyder
S R
SR
Zehner
Z E
ZE
D000230:Adenocarcinoma / Q000473:pathology; D001943:Breast Neoplasms / Q000473:pathology; D002460:Cell Line; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D017930:Genes, Reporter; D006367:HeLa Cells; D006801:Humans; D050832:Interferon-Stimulated Gene Factor 3; D007371:Interferon-gamma / Q000494:pharmacology*; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D011994:Recombinant Proteins; D012045:Regulatory Sequences, Nucleic Acid; D014157:Transcription Factors / Q000172:deficiency / Q000502:physiology*; D014158:Transcription, Genetic; D014746:Vimentin / Q000096:biosynthesis / Q000235:genetics*
D050832:Interferon-Stimulated Gene Factor 3; D009363:Neoplasm Proteins; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; D014157:Transcription Factors; D014746:Vimentin; C079868:gamma interferon activation factor; D007371:Interferon-gamma