Characterization of nuclear proteins which bind to interferon-inducible transcriptional enhancers in hematopoietic cells.
Nuclear proteins isolated from untreated lymphoid cells formed complexes with the interferon-inducible transcriptional enhancer (IITE) containing a 73- and an 84-kDa protein, whereas the nuclear proteins of untreated myeloid cells formed complexes with the IITE which contained 50-, 65-, and 73-, but not 84-kDa nuclear proteins. The difference in the molecular masses of the nuclear proteins binding to the IITE in lymphoid and myeloid cells was due to a phosphatase present in the cytoplasm of the myeloid cells. Induction of transcriptional activation by interferon was accompanied by the binding of a 95-kDa nuclear protein to the IITE 1-4 h after the start of exposure to interferon. Cycloheximide did not inhibit the binding of the 95-kDa nuclear protein or the transcriptional activation of alpha-interferon-inducible genes. These data suggest that the induction of gene transcription by alpha-interferon in hematopoietic cells may be associated with post-translational changes in a 95-kDa nuclear protein that binds to IITE, thereby leading to transcriptional activation.
Wedrychowski
A
A
Department of Hematology, University of Texas M. D. Anderson Cancer Center, Houston 77030.
Seong
D
D
Paslidis
N
N
Johnson
E
E
Howard
O M
OM
Sims
S
S
Talpaz
M
M
Kantarjian
H
H
Hester
J
J
Turpin
J
J
D001483:Base Sequence; D015152:Blotting, Northern; D002846:Chromatography, Affinity; D004268:DNA-Binding Proteins / Q000502:physiology*; D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation / Q000187:drug effects; D006412:Hematopoietic Stem Cells / Q000502:physiology; D006801:Humans; D007370:Interferon Type I / Q000494:pharmacology*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009687:Nuclear Proteins / Q000502:physiology*; D010750:Phosphoproteins / Q000502:physiology; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic
D004268:DNA-Binding Proteins; D007370:Interferon Type I; D009687:Nuclear Proteins; D010750:Phosphoproteins; D012333:RNA, Messenger; D010744:Phosphoric Monoester Hydrolases