title: Identification of proteins immunologically related to interferon regulatory factor-1 that bind with interferon regulatory factor element.
abstract: Interferon regulatory factor (IRF)-1 expression was surveyed in nontransformed and oncogene-transformed mouse fibroblasts, using Western immunoblot with an IRF-1-specific antiserum, to examine possible differences resulting from cellular transformation. Ten additional proteins that reacted with the IRF-1 antibody and that underwent specific competition by peptide antigen were observed in extracts of both nontransformed and oncogene-transformed cell lines. Cross-reacting proteins were also observed in mouse macrophage extracts. Protein was captured from fibroblast nuclear extracts, using oligonucleotides representing IRF-binding sequences linked to magnetic beads. Captured proteins were eluted and analyzed by immunoblot with anti-IRF-1. Along with 43-kDa IRF-1, 4 of the 7 nuclearly located cross-reacting proteins (97, 90, 66, and 33 kDa) were found to complex with the IRF binding element. These proteins, with an epitope in common with the IRF-1 C-terminal region and IRF element DNA sequence-binding capability, may represent new members of the IRF family.
authors.affiliation: Department of Pathology and United States Military Cancer Institute, Uniformed Services University of the Health Sciences, Bethesda, MD, 20814, USA. scontente@usuhs.mil
authors.forename: Sara
authors.initials: S
authors.lastname: Contente
authors.forename: Frank A
authors.initials: FA
authors.lastname: Attard
authors.forename: Robert M
authors.initials: RM
authors.lastname: Friedman
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D002467:Cell Nucleus / Q000737:chemistry; D003429:Cross Reactions; D000939:Epitopes / Q000276:immunology; D005347:Fibroblasts / Q000737:chemistry; D050856:Interferon Regulatory Factor-1 / Q000276:immunology*; D007372:Interferons / Q000235:genetics*; D008264:Macrophages / Q000737:chemistry; D051379:Mice; D008970:Molecular Weight; D011485:Protein Binding; D011506:Proteins / Q000276:immunology / Q000302:isolation & purification* / Q000378:metabolism*; D050436:Regulatory Elements, Transcriptional
chemical_list: D000939:Epitopes; D050856:Interferon Regulatory Factor-1; D011506:Proteins; D007372:Interferons