Nkx3.1 binds and negatively regulates the transcriptional activity of Sp-family members in prostate-derived cells

Nkx3.1 is a homeodomain-containing transcription factor that is expressed early in the development of the prostate gland and is believed to play an important role in the differentiation of prostatic epithelia. Loss of Nkx3.1 protein expression is often an early event in prostate tumorigenesis, and the abundance of Nkx3.1-negative epithelial cells increases with disease progression. In a number of systems, homeodomain proteins collaborate with zinc-finger-containing transcription factors to bind and regulate target genes. In the present paper, we report that Nkx3.1 collaborates with Sp-family members in the regulation of PSA (prostate-specific antigen) in prostate-derived cells. Nkx3.1 forms protein complexes with Sp proteins that are dependent on their respective DNA-binding domains and an N-terminal segment of Nkx3.1, and Nkx3.1 negatively regulates Sp-mediated transcription via Trichostatin A-sensitive and -insensitive mechanisms. A distal 1000 bp portion of the PSA promoter is required for transrepression by Nkx3.1, although Nkx3.1 DNA-binding activity is itself not required. We conclude that Nkx3.1 negatively regulates Sp-mediated transcription via the tethering of histone deacetylases and/or by inhibiting the association of Sp proteins with co-activators.

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Target Gene Specificity of E2F and Pocket Protein Family Members in Living Cells

Molecular and Cellular Biology ◽

10.1128/mcb.20.16.5797-5807.2000 ◽

2000 ◽

Vol 20 (16) ◽

pp. 5797-5807 ◽

Cited By ~ 162

Author(s):

Julie Wells ◽

Kathryn E. Boyd ◽

Christopher J. Fry ◽

Stephanie M. Bartley ◽

Peggy J. Farnham

Keyword(s):

Cell Cycle ◽

Target Gene ◽

Target Genes ◽

Protein Complexes ◽

Current Model ◽

Family Members ◽

Living Cells ◽

Gene Promoters ◽

Pocket Protein ◽

Protein Dna Interactions

ABSTRACT E2F-mediated transcription is thought to involve binding of an E2F-pocket protein complex to promoters in the G0 phase of the cell cycle and release of the pocket protein in late G1, followed by release of E2F in S phase. We have tested this model by monitoring protein-DNA interactions in living cells using a formaldehyde cross-linking and immunoprecipitation assay. We find that E2F target genes are bound by distinct E2F-pocket protein complexes which change as cells progress through the cell cycle. We also find that certain E2F target gene promoters are bound by pocket proteins when such promoters are transcriptionally active. Our data indicate that the current model applies only to certain E2F target genes and suggest that Rb family members may regulate transcription in both G0 and S phases. Finally, we find that a given promoter can be bound by one of several different E2F-pocket protein complexes at a given time in the cell cycle, suggesting that cell cycle-regulated transcription is a stochastic, not a predetermined, process.

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NF-κB inhibits transcription of the H+-K+-ATPase α2-subunit gene: role of histone deacetylases

AJP Renal Physiology ◽

10.1152/ajprenal.00156.2002 ◽

2002 ◽

Vol 283 (5) ◽

pp. F904-F911 ◽

Cited By ~ 49

Author(s):

Wenzheng Zhang ◽

Bruce C. Kone

Keyword(s):

Histone Deacetylases ◽

Transcriptional Control ◽

Protein Complexes ◽

Trichostatin A ◽

Collecting Duct ◽

Proximal Promoter ◽

Inner Medullary Collecting Duct ◽

Nuclear Extracts ◽

Medullary Collecting Duct

The H+-K+-ATPase α2 (HKα2) gene plays a central role in potassium homeostasis, yet little is known about its transcriptional control. We recently demonstrated that the proximal promoter confers basal transcriptional activity in mouse inner medullary collecting duct 3 cells. We sought to determine whether the κB DNA binding element at −104 to −94 influences basal HKα2 gene transcription in these cells. Recombinant NF-κB p50 footprinted the region −116/−94 in vitro. Gel shift and supershift analysis revealed NF-κB p50- and p65-containing DNA-protein complexes in nuclear extracts of mouse inner medullary collecting duct 3 cells. A promoter-luciferase construct with a mutated −104/−94 NF-κB element exhibited higher activity than the wild-type promoter in transfection assays. Overexpression of NF-κB p50, p65, or their combination trans-repressed the HKα2 promoter. The histone deacetylase (HDAC) inhibitor trichostatin A partially reversed NF-κB-mediated trans-repression of the HKα2 promoter. HDAC6 overexpression inhibited HKα2 promoter activity, and HDAC6 coimmunoprecipitated with NF-κB p50 and p65. These results suggest that HDAC6, recruited to the DNA protein complex, acts with NF-κB to suppress HKα2 transcription and identify NF-κB p50 and p65 as novel binding partners for HDAC6.

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Role of miRNALet-7and Its Major Targets in Prostate Cancer

BioMed Research International ◽

10.1155/2014/376326 ◽

2014 ◽

Vol 2014 ◽

pp. 1-14 ◽

Cited By ~ 24

Author(s):

Siegfried Wagner ◽

Anaclet Ngezahayo ◽

Hugo Murua Escobar ◽

Ingo Nolte

Keyword(s):

Prostate Cancer ◽

Prostate Specific Antigen ◽

Target Genes ◽

Prostate Cancer Screening ◽

Prostate Gland ◽

Specific Antigen ◽

Current Treatment ◽

Diagnostic Potential ◽

Major Interest ◽

Hormone Refractory

Prostate cancer is worldwide the sixth leading cause of cancer related death in men thus early detection and successful treatment are still of major interest. The commonly performed screening of the prostate-specific antigen (PSA) is controversially discussed, as in many patients the prostate-specific antigen levels are chronically elevated in the absence of cancer. Due to the unsatisfying efficiency of available prostate cancer screening markers and the current treatment outcome of the aggressive hormone refractory prostate cancer, the evaluation of novel molecular markers and targets is considered an issue of high importance. MicroRNAs are relatively stable in body fluids orchestrating simultaneously the expression of many genes. These molecules are currently discussed to bear a greater diagnostic potential than protein-coding genes, being additionally promising therapeutic drugs and/or targets. Herein we review the potential impact of the microRNAlet-7family on prostate cancer and show how deregulation of several of its target genes could influence the cellular equilibrium in the prostate gland, promoting cancer development as they do in a variety of other human malignant neoplasias.

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Faculty Opinions recommendation of Differences in DNA Binding Specificity of Floral Homeotic Protein Complexes Predict Organ-Specific Target Genes.

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

10.3410/f.727828902.793551783 ◽

2018 ◽

Author(s):

François Parcy

Keyword(s):

Dna Binding ◽

Target Genes ◽

Protein Complexes ◽

Binding Specificity ◽

Specific Target ◽

Dna Binding Specificity ◽

Organ Specific ◽

Floral Homeotic

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Direct, Androgen Receptor-Mediated Regulation of the FKBP5 Gene via a Distal Enhancer Element

Endocrinology ◽

10.1210/en.2005-1001 ◽

2006 ◽

Vol 147 (1) ◽

pp. 590-598 ◽

Cited By ~ 104

Author(s):

Jeffrey A. Magee ◽

Li-wei Chang ◽

Gary D. Stormo ◽

Jeffrey Milbrandt

Keyword(s):

Androgen Receptor ◽

Prostate Specific Antigen ◽

Target Genes ◽

Specific Antigen ◽

Proximal Promoter ◽

Distal Enhancer ◽

Normal Prostate ◽

Enhancer Element ◽

Prostate Tumorigenesis ◽

Mouse Prostate

Androgen signaling via the androgen receptor (AR) transcription factor is crucial to normal prostate homeostasis and prostate tumorigenesis. Current models of AR function are predominantly based on studies of prostate-specific antigen regulation in androgen-responsive cell lines. To expand on these in vitro paradigms, we used the mouse prostate to elucidate the mechanisms through which AR regulates another direct target, FKBP5, in vivo. FKBP5 encodes an immunophilin that has been previously implicated in glucocorticoid and progestin signaling pathways and that likely influences prostate physiology in the presence of androgens. In this work, we show that androgens directly regulate FKBP5 via an interaction between the AR and a distal enhancer located 65 kb downstream of the transcription start site in the fifth intron of the FKBP5 gene. We have found that AR selectively recruits cAMP response element-binding protein to this enhancer. These interactions, in turn, result in chromatin remodeling that affects the enhancer proper but not the FKBP5 locus as a whole. Furthermore, in contrast to prostate-specific antigen-regulatory mechanisms, we show that transactivation of the FKBP5 gene does not rely on a single looping complex to mediate communication between the distal enhancer and proximal promoter. Rather, the distal enhancer complex and basal transcription apparatus communicate indirectly with one another, implicating a regulatory mechanism that has not been previously appreciated for AR target genes.

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Cell wall integrity is compromised under temperature stress in Schizosaccharomyces pombe expressing a valproic acid-sensitive vas4 mutant

Scientific Reports ◽

10.1038/s41598-021-92466-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sen Qiao ◽

Xiaofang Luo ◽

Hui Wang ◽

Yue Fang ◽

Lili Zhang

Keyword(s):

Valproic Acid ◽

Cell Wall ◽

Temperature Stress ◽

Histone Deacetylases ◽

Target Genes ◽

Trichostatin A ◽

Anticonvulsant Drug ◽

Cell Wall Integrity ◽

Loss Of Function ◽

Copii Vesicles

AbstractValproic acid (VPA) is widely used as a eutherapeutic and safe anticonvulsant drug, but the mechanism is not well elucidated. Histone deacetylases (HDACs) were first identified as direct targets of VPA. Many loss-of function mutants in S. pombe have been shown to be VPA sensitive but not sensitive to other HDAC inhibitors, such as sodium butyrate or trichostatin A (TSA). This difference suggests that there are multiple VPA target genes. In the current study, we isolated a VPA-sensitive (vas) mutant, vas4-1, and cloned the VPA target gene vas4+/vrg4+ by performing complementation experiments. The vas4+/vrg4+ gene encodes a putative Golgi GDP-mannose transporter, Vrg4, which is highly homologous with ScVrg4p. Physiological experiments indicated that SpVrg4p is involved in maintaining cell wall integrity (CWI) under high- or low-temperature stress. The results of a coimmunoprecipitation assay suggested that SpVrg4p may be transferred from the ER to the Golgi through SpGot1p loaded COPII vesicles, and both single and double mutations (S263C and A271V) in SpVrg4p compromised this transfer. Our results suggested that CWI in S. pombe is compromised under temperature stress by the VPA-sensitive vas4 mutant.

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Human Slug Is a Repressor That Localizes to Sites of Active Transcription

Molecular and Cellular Biology ◽

10.1128/mcb.20.14.5087-5095.2000 ◽

2000 ◽

Vol 20 (14) ◽

pp. 5087-5095 ◽

Cited By ~ 79

Author(s):

Kirugaval Hemavathy ◽

Siradanahalli C. Guru ◽

John Harris ◽

J. Don Chen ◽

Y. Tony Ip

Keyword(s):

Dna Binding ◽

Cell Fate ◽

Histone Deacetylases ◽

Molecular Mechanisms ◽

Target Genes ◽

Protein Localization ◽

Zinc Fingers ◽

Cell Movement ◽

Left Right Asymmetry ◽

And Function

ABSTRACT Snail/Slug family proteins have been identified in diverse species of both vertebrates and invertebrates. The proteins contain four to six zinc fingers and function as DNA-binding transcriptional regulators. Various members of the family have been demonstrated to regulate cell movement, neural cell fate, left-right asymmetry, cell cycle, and apoptosis. However, the molecular mechanisms of how these regulators function and the target genes involved are largely unknown. In this report, we demonstrate that human Slug (hSlug) is a repressor and modulates both activator-dependent and basal transcription. The repression depends on the C-terminal DNA-binding zinc fingers and on a separable repression domain located in the N terminus. This domain may recruit histone deacetylases to modify the chromatin and effect repression. Protein localization study demonstrates that hSlug is present in discrete foci in the nucleus. This subnuclear pattern does not colocalize with the PML foci or the coiled bodies. Instead, the hSlug foci overlap extensively with areas of the SC-35 staining, some of which have been suggested to be sites of active splicing or transcription. These results lead us to postulate that hSlug localizes to target promoters, where activation occurs, to repress basal and activator-mediated transcription.

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Biological roles and mechanistic actions of co-repressor complexes

Journal of Cell Science ◽

10.1242/jcs.115.4.689 ◽

2002 ◽

Vol 115 (4) ◽

pp. 689-698 ◽

Cited By ~ 12

Author(s):

Kristen Jepsen ◽

Michael G. Rosenfeld

Keyword(s):

Dna Binding ◽

Histone Deacetylase ◽

Transcriptional Repression ◽

Target Genes ◽

Protein Complexes ◽

Genetically Engineered ◽

Repressor Proteins ◽

Multiple Protein ◽

Genetically Engineered Mice ◽

Cell Signaling Pathways

Transcriptional repression, which plays a crucial role in diverse biological processes, is mediated in part by non-DNA-binding co-repressors. The closely related co-repressor proteins N-CoR and SMRT, although originally identified on the basis of their ability to associate with and confer transcriptional repression through nuclear receptors, have been shown to be recruited to many classes of transcription factor and are in fact components of multiple protein complexes containing histone deacetylase proteins. This association with histone deacetylase activity provides an important component of the mechanism that allows DNA-binding proteins interacting with N-CoR or SMRT to repress transcription of specific target genes. Both N-CoR and SMRT are important targets for cell signaling pathways, which influence their expression levels, subcellular localization and association with other proteins. Recently, the biological importance of these proteins has been revealed by studies of genetically engineered mice and human diseases such as acute promyelocytic leukemia (APL) and resistance to thyroid hormone(RTH).

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Helix-loop-helix proteins LYL1 and E2a form heterodimeric complexes with distinctive DNA-binding properties in hematolymphoid cells.

Molecular and Cellular Biology ◽

10.1128/mcb.16.5.2394 ◽

1996 ◽

Vol 16 (5) ◽

pp. 2394-2401 ◽

Cited By ~ 37

Author(s):

A Miyamoto ◽

X Cui ◽

L Naumovski ◽

M L Cleary

Keyword(s):

Dna Binding ◽

Cell Lines ◽

Target Genes ◽

Protein Complexes ◽

Lymphoblastic Leukemia ◽

Cell Receptor ◽

Binding Properties ◽

Helix Loop Helix ◽

Dna Binding Properties

LYL1 is a basic helix-loop-helix (HLH) protein that was originally discovered because of its translocation into the beta T-cell receptor locus in an acute lymphoblastic leukemia. LYL1 is expressed in many hematolymphoid cells, with the notable exceptions of thymocytes and T cells. Using the yeast two-hybrid system to screen a cDNA library constructed from B cells, we identified the E-box-binding proteins E12 and E47 as potential lymphoid dimerization partners for LYL1. The interaction of LYL1 with E2a proteins was further characterized in vitro and shown to require the HLH motifs of both proteins. Immunoprecipitation analyses showed that in T-ALL and other cell lines, endogenous LYL1 exists in a complex with E2a proteins. A preferred DNA-binding sequence, 5'-AACAGATG(T/g)T-3', for the LYL1-E2a heterodimer was determined by PCR-assisted site selection. Endogenous protein complexes containing both LYL1 and E2a bound this sequence in various LYL1-expressing cell lines and could distinguish between the LYL1 consensus and muE2 sites. These data demonstrate that E2a proteins serve as dimerization partners for the basic HLH protein LYL1 to form complexes with distinctive DNA-binding properties and support the hypothesis that the leukemic properties of the LYL1 and TAL subfamily of HLH proteins could be mediated by recognition of a common set of target genes as heterodimeric complexes with class I HLH proteins.

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