HMBOX1, homeobox transcription factor, negatively regulates interferon-γ production in natural killer cells.

Abstract

HMBOX1 is a new member of homeobox family and predicted to be a transcriptional repressor, its function in NK cells is completely unclear. Previously we found that overexpression of HMBOX1 downregulated mRNA level of IFN-γ in NK cells during our gene screening work. In present study, we investigate the relationship between HMBOX1 and IFN-γ in detail. Firstly, we describe the properties of HMBOX1 gene transcription in activated NK cells, and found that the transcriptional levels of HMBOX1 were significantly decreased in NK cells after activated by IL-2, IL-15 and IL-12, which was opposite to the expression profile of IFN-γ. Subsequently, over-expression of HMBOX1 significantly inhibited the expression and production of IFN-γ in NK cells in response to the stimulation of tumor cell K562 or PMA/ionomycin. Additionally, by luciferase reporter assay, HMBOX1 displayed suppressive effect on the transcription activity of IFN-γ promoter. These findings indicated that HMBOX1 may function as a negative regulator of IFN-γ in NK cells.

• Authors: Longyan Wu, Cai Zhang, Xiaodong Zheng, Zhigang Tian, Jian Zhang
• Journal: International immunopharmacology (Int Immunopharmacol) Vol. 11 Issue 11 Pg. 1895-900 (Nov 2011) ISSN: 1878-1705 [Electronic] Netherlands
• PMID: 21839858 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2011 Elsevier B.V. All rights reserved.

Chemical References

• Cytokines
• HMBOX1 protein, human
• Homeodomain Proteins
• Interferon-gamma
• Luciferases

Topics

• Cytokines (immunology)
• Down-Regulation
• Flow Cytometry
• HEK293 Cells
• Homeodomain Proteins (genetics, physiology)
• Humans
• Interferon-gamma (genetics)
• K562 Cells
• Killer Cells, Natural (immunology, metabolism)
• Luciferases (genetics)
• Lymphocyte Activation (immunology)
• Promoter Regions, Genetic
• Reverse Transcriptase Polymerase Chain Reaction
• Transcription, Genetic