Interferon regulatory factor-1 (IRF-1) is an interferon-induced transcriptional activator that suppresses tumors by impeding cell proliferation. Recently, we demonstrated that the level of SUMOylated IRF-1 is elevated in tumor cells, and that SUMOylation of IRF-1 attenuates its tumor-suppressive function. Here we report that SUMOylated IRF-1 mimics IRF-2, an antagonistic repressor, and shows oncogenic potential. To demonstrate the role of SUMOylated IRF-1 in tumorigenesis, we used SUMO-IRF-1 recombinant protein. Stable expression of SUMO-IRF-1 in NIH3T3 cells resulted in focus formation and anchorage-independent growth in soft agar. Inoculation of SUMO-IRF-1-transfected cells into athymic nude mice resulted in tumor formation and infiltration of adipose tissues. Finally, we demonstrated that SUMO-IRF-1 transforms NIH3T3 cells in a dose-dependent manner suggesting that SUMOylated IRF-1 may act as an oncogenic protein in tumor cells.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.bbrc.2009.11.166 | DOI Listing |
Dis Markers
September 2022
Department of Liver Transplantation, The Second Xiangya Hospital of Central South University, Changsha 410011, China.
Recently, attentions have come to the alleviatory effect of protein inhibitor of activated STAT1 (PIAS1) in hepatic ischemia-reperfusion injury (HIRI), but the underlying molecular mechanistic actions remain largely unknown, which were illustrated in the present study. Microarray-based analysis predicted a possible regulatory mechanism involving the PIAS1/NFATc1/HDAC1/IRF-1/p38 MAPK signaling axis in HIRI. Then, growth dynamics of hypoxia/reoxygenation- (H/R-) exposed hepatocytes and liver injury of HIRI-like mice were delineated after the alteration of the PIAS1 expression.
View Article and Find Full Text PDFToxicol In Vitro
October 2014
Department of Orthopedics, Yantaishan Hospital, Yantai 264025, Shandong Province, China. Electronic address:
Osteoarthritis (OA), one of the most common joint disorders, is one of the leading causes of disability among the elderly. Proinflammatory cytokines, such as interleukin (IL)-1β, which is synthesized locally by synovial cells and chondrocytes, have been shown to play a critical role in sustaining cartilage damage in arthritis by creating an imbalance between cartilage degradation and the repair process. Alpha-lipoic acid (α-LA), which is synthesized in animal and plant tissues, has demonstrated its protective effects in a variety of diseases.
View Article and Find Full Text PDFBMC Genomics
November 2013
Institute of Microbiology and Immunology, National Yang-Ming University, Taipei 11221, Taiwan.
Background: SUMOylation, as part of the epigenetic regulation of transcription, has been intensively studied in lower eukaryotes that contain only a single SUMO protein; however, the functions of SUMOylation during mammalian epigenetic transcriptional regulation are largely uncharacterized. Mammals express three major SUMO paralogues: SUMO-1, SUMO-2, and SUMO-3 (normally referred to as SUMO-1 and SUMO-2/3). Herpesviruses, including Kaposi's sarcoma associated herpesvirus (KSHV), seem to have evolved mechanisms that directly or indirectly modulate the SUMO machinery in order to evade host immune surveillance, thus advancing their survival.
View Article and Find Full Text PDFBiochem Biophys Res Commun
January 2010
Yonsei University, Division of Biological Science and Technology, Wonju 220-100, Republic of Korea.
Interferon regulatory factor-1 (IRF-1) is an interferon-induced transcriptional activator that suppresses tumors by impeding cell proliferation. Recently, we demonstrated that the level of SUMOylated IRF-1 is elevated in tumor cells, and that SUMOylation of IRF-1 attenuates its tumor-suppressive function. Here we report that SUMOylated IRF-1 mimics IRF-2, an antagonistic repressor, and shows oncogenic potential.
View Article and Find Full Text PDFBiochem Biophys Res Commun
December 2008
Department of Molecular Biology, Dankook University, Gyeonggi-do 448-701, Republic of Korea.
To characterize the regulatory mechanism of the interferon regulatory factor (IRF) family, we performed yeast two-hybrid screening with IRF-2 and isolated the small ubiquitin-related modifier (SUMO)-conjugating enzyme Ubc9, which also interacts with other IRF family members IRF-1 and ICSBP. Subsequent assays indicated that among the IRF family members, only IRF-1 interacts with SUMO-1 through its transcriptional activation domain. The interaction between IRF-1 and SUMO-1 was confirmed in vitro by GST pull-down assays and in vivo by co-localization assays.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!