2. Academic Validation
  3. A ubiquitin E3 ligase Efp is up-regulated by interferons and conjugated with ISG15

A ubiquitin E3 ligase Efp is up-regulated by interferons and conjugated with ISG15

  • Biochem Biophys Res Commun. 2006 Dec 15;351(2):540-6. doi: 10.1016/j.bbrc.2006.10.061.
Norie Nakasato 1,  Kazuhiro Ikeda,  Tomohiko Urano,  Kuniko Horie-Inoue,  Satoru Takeda,  Satoshi Inoue
Affiliations

Affiliation

  • 1 Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama, Japan.
PMID: 17069755 DOI: 10.1016/j.bbrc.2006.10.061
Abstract

Interferon (IFN) regulates various target genes that mediate important roles in immune responses such as Antiviral state. Protein ISG15-conjugation (ISGylation) is implicated in the IFN-induced Antiviral response. Here we demonstrate that Efp mRNA as well as protein expression could be up-regulated by Type I IFN in HeLa cells and HepG2 cells. Luciferase assay reveals that the first intron of Efp gene contains a functional interferon-stimulated response element (ISRE) and electrophoretic mobility shift assay shows that the ISRE binds to signal transducer and activator of transcription 1 (STAT1). Chromatin immunoprecipitation assays have shown that the ISRE recruits STAT1 in vivo IFN-dependently. Moreover, we demonstrate that Efp protein could be conjugated with not only ubiquitin but also ISG15. These data suggest that Efp is an IFN-responsive gene that potentially mediates IFN actions, involved in ISGylation and ubiquitination of proteins including Efp itself.

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