Zinc Finger Protein Gfi1 Controls the Endotoxin-Mediated Toll-Like Receptor Inflammatory Response by Antagonizing NF-κB p65

ABSTRACT Endotoxin (bacterial lipopolysaccharide [LPS]) causes fatal septic shock via the Toll-like receptor 4 (TLR-4) protein present on innate immunity effector cells, which activates nuclear factor kappa B (NF-κB), inducing proinflammatory cytokines, including tumor necrosis factor alpha (TNF-α). An early step in this process involves nuclear sequestration of the p65-RelA NF-κB subunit, enabling transcriptional activation of target inflammatory cytokine genes. Here, we analyzed the role of the nuclear zinc finger protein Gfi1 in the TLR response using primary bone marrow-derived macrophages. We show that upon LPS stimulation, expression of Gfi1 is induced with kinetics similar to those of nuclear translocation of p65 and that Gfi1 interacts with p65 and inhibits p65-mediated transcriptional transactivation by interfering with p65 binding to target gene promoter DNA. Gfi1-deficient macrophages show abnormally high mRNA levels of the TNF-α gene and many other p65 target genes and a higher rate of TNF promoter occupancy by p65 than wild-type cells after LPS stimulation, suggesting that Gfi1 functions as an antagonist of NF-κB activity at the level of promoter binding. Our findings identify a new function of Gfi1 as a general negative regulator of the endotoxin-initiated innate immune responses, including septic shock and possibly other severe inflammatory diseases.

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Regulation of epithelial sodium transport by promyelocytic leukemia zinc finger protein

AJP Renal Physiology ◽

10.1152/ajprenal.00573.2007 ◽

2008 ◽

Vol 295 (1) ◽

pp. F18-F26 ◽

Cited By ~ 15

Author(s):

Anikó Náray-Fejes-Tóth ◽

Cary Boyd ◽

Géza Fejes-Tóth

Keyword(s):

Zinc Finger ◽

Zinc Finger Protein ◽

Promyelocytic Leukemia ◽

Negative Regulator ◽

Sodium Reabsorption ◽

Target Cells ◽

Mrna Levels ◽

Na Transport ◽

Promyelocytic Leukemia Zinc Finger ◽

Finger Protein

Aldosterone is the principal regulator of Na homeostasis, and thereby blood pressure. One of the main targets of aldosterone is the epithelial Na channel (ENaC) located in the apical membrane of target cells. Previous studies identified several genes involved in the regulation of ENaC such as SGK1; however, SGK1 knockout mice have only a mild salt-losing phenotype, indicating that further genes must be involved in the action of aldosterone. In our search for further aldosterone-regulated genes, we discovered that aldosterone, at physiological concentrations, induces the expression of the promyelocytic leukemia zinc finger protein (PLZF) in renal cortical collecting duct (CCD) cell lines that stably express mineralocorticoid receptors (MRs). This effect is rapid and does not require de novo protein synthesis, suggesting a direct action. Surprisingly, stable overexpression of human or mouse PLZF isoforms significantly decreased transepithelial Na transport in CCD cells while having no effect on the integrity of the monolayers. In parallel with the decline in Na transport, PLZF suppressed the mRNA levels of β- and γ-ENaC subunits. These observations suggest that PLZF is a negative regulator of ENaC in renal epithelial cells and might be part of a negative feedback loop that limits aldosterone's stimulatory effects on sodium reabsorption.

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Transcriptional activation of the tumor necrosis factor alpha-inducible zinc finger protein, A20, is mediated by kappa B elements.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)37138-8 ◽

1992 ◽

Vol 267 (25) ◽

pp. 17971-17976

Author(s):

A Krikos ◽

C.D. Laherty ◽

V.M. Dixit

Keyword(s):

Tumor Necrosis Factor ◽

Zinc Finger ◽

Tumor Necrosis Factor Alpha ◽

Transcriptional Activation ◽

Tumor Necrosis ◽

Zinc Finger Protein ◽

Necrosis Factor Alpha ◽

Finger Protein ◽

Factor Alpha ◽

Necrosis Factor

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Zinc-finger protein MdBBX7/MdCOL9, a target of MdMIEL1 E3 ligase, confers drought tolerance in apple

Plant Physiology ◽

10.1093/plphys/kiab420 ◽

2021 ◽

Author(s):

Pengxiang Chen ◽

Fang Zhi ◽

Xuewei Li ◽

Wenyun Shen ◽

Mingjia Yan ◽

...

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Zinc Finger ◽

Zinc Finger Protein ◽

E3 Ligase ◽

26S Proteasome ◽

Negative Regulator ◽

Binding Motif ◽

Ethylene Response Factor ◽

Finger Protein

Abstract Water deficit is one of the main challenges for apple (Malus × domestica) growth and productivity. Breeding drought-tolerant cultivars depends on a thorough understanding of the drought responses of apple trees. Here, we identified the zinc-finger protein B-BOX 7/CONSTANS-LIKE 9 (MdBBX7/MdCOL9), which plays a positive role in apple drought tolerance. The overexpression of MdBBX7 enhanced drought tolerance, whereas knocking down MdBBX7 expression reduced it. Chromatin immunoprecipitation-sequencing (ChIP-seq) analysis identified one cis-element of MdBBX7, CCTTG, as well as its known binding motif, the T/G box. ChIP-seq and RNA-seq identified 1,197 direct targets of MdBBX7, including ETHYLENE RESPONSE FACTOR (ERF1), EARLY RESPONSIVE TO DEHYDRATION 15 (ERD15), and GOLDEN2-LIKE 1 (GLK1) and these were further verified by ChIP-qPCR and electronic mobility shift assays. Yeast two-hybrid screen identified an interacting protein of MdBBX7, RING-type E3 ligase MYB30-INTERACTING E3 LIGASE 1 (MIEL1). Further examination revealed that MdMIEL1 could mediate the ubiquitination and degradation of MdBBX7 by the 26S proteasome pathway. Genetic interaction analysis suggested that MdMIEL1 acts as an upstream factor of MdBBX7. In addition, MdMIEL1 was a negative regulator of the apple drought stress response. Taken together, our results illustrate the molecular mechanisms by which the MdMIEL1–MdBBX7 module influences the response of apple to drought stress.

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Single zinc-finger extension: enhancing transcriptional activity and specificity of three-zinc-finger proteins

Biological Chemistry ◽

10.1515/bc.2005.012 ◽

2005 ◽

Vol 386 (2) ◽

pp. 95-99 ◽

Cited By ~ 1

Author(s):

Alexander E.F. Smith ◽

Farzin Farzaneh ◽

Kevin G. Ford

Keyword(s):

Transcription Factors ◽

Fusion Protein ◽

Zinc Finger ◽

Protein Interactions ◽

Transcriptional Activation ◽

Zinc Finger Protein ◽

Zinc Finger Proteins ◽

Finger Protein ◽

Finger Extension ◽

Vp16 Fusion

AbstractIn order to demonstrate that an existing zinc-finger protein can be simply modified to enhance DNA binding and sequence discrimination in both episomal and chromatin contexts using existing zinc-finger DNA recognition code data, and without recourse to phage display and selection strategies, we have examined the consequences of a single zinc-finger extension to a synthetic three-zinc-finger VP16 fusion protein, on transcriptional activation from model target promoters harbouring the zinc-finger binding sequences. We report a nearly 10-fold enhanced transcriptional activation by the four-zinc-finger VP16 fusion protein relative to the progenitor three-finger VP16 protein in transient assays and a greater than five-fold enhancement in stable reporter-gene expression assays. A marked decrease in transcriptional activation was evident for the four-zinc-finger derivative from mutated regulatory regions compared to the progenitor protein, as a result of recognition site-size extension. This discriminatory effect was shown to be protein concentration-dependent. These observations suggest that four-zinc-finger proteins are stable functional motifs that can be a significant improvement over the progenitor three-zinc-finger protein, both in terms of specificity and the ability to target transcriptional function to promoters, and that single zinc-finger extension can therefore have a significant impact on DNA zinc-finger protein interactions. This is a simple route for modifying or enhancing the binding properties of existing synthetic zinc-finger-based transcription factors and may be particularly suited for the modification of endogenous zinc-finger transcription factors for promoter biasing applications.

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KRAB-Zinc Finger Protein ZNF268a Deficiency Attenuates the Virus-Induced Pro-Inflammatory Response by Preventing IKK Complex Assembly

Cells ◽

10.3390/cells8121604 ◽

2019 ◽

Vol 8 (12) ◽

pp. 1604 ◽

Cited By ~ 1

Author(s):

Yi Liu ◽

Wei Yin ◽

Jingwen Wang ◽

Yucong Lei ◽

Guihong Sun ◽

...

Keyword(s):

Inflammatory Response ◽

Viral Infection ◽

Zinc Finger ◽

Cytokine Production ◽

Zinc Finger Protein ◽

Nuclear Translocation ◽

Sendai Virus ◽

Positive Role ◽

Finger Protein ◽

Ikk Complex

Despite progress in understanding how virus-induced, NF-κB-dependent pro-inflammatory cytokines are regulated, there are still factors and mechanisms that remain to be explored. We aimed to uncover the relationship between KRAB-zinc finger protein ZNF268a and NF-κB-mediated cytokine production in response to viral infection. To this end, we established a ZNF268a-knockout cell line using a pair of sgRNAs that simultaneously target exon 3 in the coding sequence of the ZNF268 gene in HEK293T. HEK293T cells lacking ZNF268a showed less cytokine expression at the transcription and protein levels in response to Sendai virus/vesicular stomatitis virus (SeV/VSV) infection than wild-type cells. Consistent with HEK293T, knock-down of ZNF268a by siRNAs in THP-1 cells significantly dampened the inflammatory response. Mechanistically, ZNF268a facilitated NF-κB activation by targeting IKKα, helping to maintain the IKK signaling complex and thus enabling proper p65 phosphorylation and nuclear translocation. Taken together, our data suggest that ZNF268a plays a positive role in the regulation of virus-induced pro-inflammatory cytokine production. By interacting with IKKα, ZNF268a promotes NF-κB signal transduction upon viral infection by helping to maintain the association between IKK complex subunits.

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Broadly active zinc finger protein-guided transcriptional activation of HIV-1

Molecular Therapy — Methods & Clinical Development ◽

10.1016/j.omtm.2020.10.018 ◽

2021 ◽

Vol 20 ◽

pp. 18-29

Author(s):

Tristan A. Scott ◽

Denis O’Meally ◽

Nicole Anne Grepo ◽

Citradewi Soemardy ◽

Daniel C. Lazar ◽

...

Keyword(s):

Zinc Finger ◽

Transcriptional Activation ◽

Zinc Finger Protein ◽

Finger Protein ◽

Hiv 1

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The Zinc Finger Protein A20 Inhibits TNF-induced NF-κB–dependent Gene Expression by Interfering with an RIP- or TRAF2-mediated Transactivation Signal and Directly Binds to a Novel NF-κB–inhibiting Protein ABIN

The Journal of Cell Biology ◽

10.1083/jcb.145.7.1471 ◽

1999 ◽

Vol 145 (7) ◽

pp. 1471-1482 ◽

Cited By ~ 228

Author(s):

Karen Heyninck ◽

Dirk De Valck ◽

Wim Vanden Berghe ◽

Wim Van Criekinge ◽

Roland Contreras ◽

...

Keyword(s):

Gene Expression ◽

Zinc Finger ◽

Zinc Finger Protein ◽

Nuclear Translocation ◽

Tnf Receptor ◽

Cell Leukemia Virus Type ◽

Finger Protein ◽

Iκb Kinase ◽

Human T Cell ◽

Inhibiting Protein

The zinc finger protein A20 is a tumor necrosis factor (TNF)– and interleukin 1 (IL-1)-inducible protein that negatively regulates nuclear factor-kappa B (NF-κB)–dependent gene expression. However, the molecular mechanism by which A20 exerts this effect is still unclear. We show that A20 does not inhibit TNF- induced nuclear translocation and DNA binding of NF-κB, although it completely prevents the TNF- induced activation of an NF-κB–dependent reporter gene, as well as TNF-induced IL-6 and granulocyte macrophage–colony stimulating factor gene expression. Moreover, NF-κB activation induced by overexpression of the TNF receptor–associated proteins TNF receptor–associated death domain protein (TRADD), receptor interacting protein (RIP), and TNF recep- tor–associated factor 2 (TRAF2) was also inhibited by expression of A20, whereas NF-κB activation induced by overexpression of NF-κB–inducing kinase (NIK) or the human T cell leukemia virus type 1 (HTLV-1) Tax was unaffected. These results demonstrate that A20 inhibits NF-κB–dependent gene expression by interfering with a novel TNF-induced and RIP- or TRAF2-mediated pathway that is different from the NIK–IκB kinase pathway and that is specifically involved in the transactivation of NF-κB. Via yeast two-hybrid screening, we found that A20 binds to a novel protein, ABIN, which mimics the NF-κB inhibiting effects of A20 upon overexpression, suggesting that the effect of A20 is mediated by its interaction with this NF-κB inhibiting protein, ABIN.

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