The neurogenic suppressor of hairless DNA-binding protein mediates the transcriptional activation of the enhancer of split complex genes triggered by Notch signaling.

ABSTRACT The RBP-J/Su(H) DNA-binding protein plays a key role in transcriptional regulation by targeting Epstein-Barr virus nuclear antigen 2 (EBNA2) and the intracellular portions of Notch receptors to specific promoters. Using the yeast two-hybrid system, we isolated a LIM-only protein, KyoT, which physically interacts with RBP-J. Differential splicing gave rise to two transcripts of theKyoT gene, KyoT1 and KyoT2, that encoded proteins with four and two LIM domains, respectively. With differential splicing resulting in deletion of an exon, KyoT2 lacked two LIM domains from the C terminus and had a frameshift in the last exon, creating the RBP-J-binding region in the C terminus. KyoT1 had a negligible level of interaction with RBP-J. Strong expression of KyoT mRNAs was detected in skeletal muscle and lung, with a predominance of KyoT1 mRNA. When expressed in F9 embryonal carcinoma cells, KyoT1 and KyoT2 were localized in the cytoplasm and the nucleus, respectively. The binding site of KyoT2 on RBP-J overlaps those of EBNA2 and Notch1 but is distinct from that of Hairless, the negative regulator of RBP-J-mediated transcription in Drosophila. KyoT2 but not KyoT1 repressed the RBP-J-mediated transcriptional activation by EBNA2 and Notch1 by competing with them for binding to RBP-J and by dislocating RBP-J from DNA. KyoT2 is a novel negative regulatory molecule for RBP-J-mediated transcription in mammalian systems.

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Pseudomonas aeruginosa AlgZ, a ribbon-helix-helix DNA-binding protein, is essential for alginate synthesis and algD transcriptional activation

Molecular Microbiology ◽

10.1046/j.1365-2958.1999.01550.x ◽

1999 ◽

Vol 33 (5) ◽

pp. 1069-1080 ◽

Cited By ~ 39

Author(s):

Patricia J. Baynham ◽

Amy L. Brown ◽

Lisa L. Hall ◽

Daniel J. Wozniak

Keyword(s):

Pseudomonas Aeruginosa ◽

Dna Binding ◽

Transcriptional Activation ◽

Binding Protein ◽

Dna Binding Protein

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Faculty Opinions recommendation of A trihelix DNA binding protein counterbalances hypoxia-responsive transcriptional activation in Arabidopsis.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718877929.793500916 ◽

2014 ◽

Author(s):

David Smyth

Keyword(s):

Dna Binding ◽

Transcriptional Activation ◽

Binding Protein ◽

Dna Binding Protein

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Tumor suppressor Smad4 is a transforming growth factor beta-inducible DNA binding protein.

Molecular and Cellular Biology ◽

10.1128/mcb.17.12.7019 ◽

1997 ◽

Vol 17 (12) ◽

pp. 7019-7028 ◽

Cited By ~ 202

Author(s):

J M Yingling ◽

M B Datto ◽

C Wong ◽

J P Frederick ◽

N T Liberati ◽

...

Keyword(s):

Growth Factor ◽

Dna Binding ◽

Binding Site ◽

Transforming Growth Factor Beta ◽

Transcriptional Activation ◽

Transforming Growth Factor ◽

Binding Protein ◽

Dna Binding Protein ◽

Tgf Beta ◽

Growth Factor Beta

Members of the Smad family of proteins are thought to play important roles in transforming growth factor beta (TGF-beta)-mediated signal transduction. In response to TGF-beta, specific Smads become inducibly phosphorylated, form heteromers with Smad4, and undergo nuclear accumulation. In addition, overexpression of specific Smad combinations can mimic the transcriptional effect of TGF-beta on both the plasminogen activator inhibitor 1 (PAI-1) promoter and the reporter construct p3TP-Lux. Although these data suggest a role for Smads in regulating transcription, the precise nuclear function of these heteromeric Smad complexes remains largely unknown. Here we show that in Mv1Lu cells Smad3 and Smad4 form a TGF-beta-induced, phosphorylation-dependent, DNA binding complex that specifically recognizes a bipartite binding site within p3TP-Lux. Furthermore, we demonstrate that Smad4 itself is a DNA binding protein which recognizes the same sequence. Interestingly, mutations which eliminate the Smad DNA binding site do not interfere with either TGF-beta-dependent transcriptional activation or activation by Smad3/Smad4 cooverexpression. In contrast, mutation of adjacent AP1 sites within this context eliminates both TGF-beta-dependent transcriptional activation and activation in response to Smad3/Smad4 cooverexpression. Furthermore, concatemerized AP1 sites, in isolation, are activated by Smad3/Smad4 cooverexpression and, to a certain extent, by TGF-beta. Taken together, these data suggest that the Smad3/Smad4 complex has at least two separable nuclear functions: it forms a rapid, yet transient sequence-specific DNA binding complex, and it potentiates AP1-dependent transcriptional activation.

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The DNA-binding protein RAP1 is required for efficient transcriptional activation of the yeast PYK glycolytic gene

Current Genetics ◽

10.1007/bf00309909 ◽

1990 ◽

Vol 18 (5) ◽

pp. 405-412 ◽

Cited By ~ 12

Author(s):

J. Bryan McNeil ◽

P. Dykshoorn ◽

J. N. Huy ◽

S. Small

Keyword(s):

Dna Binding ◽

Transcriptional Activation ◽

Binding Protein ◽

Dna Binding Protein ◽

Glycolytic Gene

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The Xenopus homolog of Drosophila Suppressor of Hairless mediates Notch signaling during primary neurogenesis

Development ◽

10.1242/dev.124.3.693 ◽

1997 ◽

Vol 124 (3) ◽

pp. 693-702 ◽

Cited By ~ 23

Author(s):

D.A. Wettstein ◽

D.L. Turner ◽

C. Kintner

Keyword(s):

Dna Binding ◽

Notch Signaling ◽

Signaling Pathway ◽

Cell Interaction ◽

Notch Signaling Pathway ◽

Notch 1 ◽

Xenopus Embryos ◽

Suppressor Of Hairless ◽

Primary Neurogenesis ◽

Enhancer Of Split

The X-Notch-1 receptor, and its putative ligand, X-Delta-1, are thought to mediate an inhibitory cell-cell interaction, called lateral inhibition, that limits the number of primary neurons that form in Xenopus embryos. The expression of Xenopus ESR-1, a gene related to Drosophila Enhancer of split, appears to be induced by Notch signaling during this process. To determine how the activation of X-Notch-1 induces ESR-1 expression and regulates primary neurogenesis, we isolated the Xenopus homolog of Suppressor of Hairless (X-Su(H)), a component of the Notch signaling pathway in Drosophila. Using animal cap assays, we show that X-Su(H) induces ESR-1 expression, perhaps directly, when modified by the addition of ankyrin repeats. Using a DNA binding mutant of X-Su(H), we show that X-Su(H) activity is required for induction of ESR-1. Finally, expression of the DNA binding mutant in embryos leads to a neurogenic phenotype as well as increased expression of both X-Delta-1 and XNGNR1, a proneural gene expressed during primary neurogenesis. These results suggest that activation of X-Su(H) is a key step in the Notch signaling pathway during primary neurogenesis in Xenopus embryos.

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Synergy between suppressor of Hairless and Notch in regulation of Enhancer of split m gamma and m delta expression.

Molecular and Cellular Biology ◽

10.1128/mcb.17.9.5620 ◽

1997 ◽

Vol 17 (9) ◽

pp. 5620-5628 ◽

Cited By ~ 38

Author(s):

D S Eastman ◽

R Slee ◽

E Skoufos ◽

L Bangalore ◽

S Bray ◽

...

Keyword(s):

Notch Signaling ◽

Signaling Pathway ◽

Cell Fate ◽

Transcriptional Activation ◽

Cultured Cells ◽

Notch Signaling Pathway ◽

Cell Fate Decisions ◽

Suppressor Of Hairless ◽

Enhancer Of Split

The Notch signaling pathway is known to regulate cell fate decisions in a variety of organisms from worms to humans. Although several components of the pathway have been characterized, the actual mechanism and molecular results of signaling remain elusive. We have examined the role of the Notch signaling pathway in the transcriptional regulation of two Drosophila Enhancer of split [E(spl)] genes, whose gene products have been shown to be downstream players in the pathway. Using a reporter assay system in Drosophila tissue culture cells, we have observed a significant induction of E(spl) m gamma and m delta expression after cotransfection with activated Notch. Characterization of the 5' regulatory regions of these two genes led to the identification of a number of target sites for the Suppressor of Hairless [Su(H)] protein, a transcription factor activated by Notch signaling. We show that Notch-inducible expression of E(spl) m gamma and m delta both in cultured cells and in vivo is dependent on functional Su(H). Although overexpression of Su(H) augments the level of induction of the reporter genes by activated Notch, Su(H) alone is insufficient to produce high levels of transcriptional activation. Despite the synergy observed between activated Notch and Su(H), the former affects neither the nuclear localization nor the DNA binding activity of the latter.

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