scholarly journals Tuned polymerization of the transcription factor Yan limits off-DNA sequestration to confer context-specific repression

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
C Matthew Hope ◽  
Jemma L Webber ◽  
Sherzod A Tokamov ◽  
Ilaria Rebay
Keyword(s):  
Transcription Factor ◽  
Protein Interactions ◽  
Genetic Interaction ◽  
Protein Protein Interactions ◽  
Regulate Gene Expression ◽  
Sam Domain ◽  
Ets Domain ◽  
Context Specific ◽  
Regulatory Decisions ◽  
Type Specification

During development, transcriptional complexes at enhancers regulate gene expression in complex spatiotemporal patterns. To achieve robust expression without spurious activation, the affinity and specificity of transcription factor–DNA interactions must be precisely balanced. Protein–protein interactions among transcription factors are also critical, yet how their affinities impact enhancer output is not understood. The Drosophila transcription factor Yan provides a well-suited model to address this, as its function depends on the coordinated activities of two independent and essential domains: the DNA-binding ETS domain and the self-associating SAM domain. To explore how protein–protein affinity influences Yan function, we engineered mutants that increase SAM affinity over four orders of magnitude. This produced a dramatic subcellular redistribution of Yan into punctate structures, reduced repressive output and compromised survival. Cell-type specification and genetic interaction defects suggest distinct requirements for polymerization in different regulatory decisions. We conclude that tuned protein–protein interactions enable the dynamic spectrum of complexes that are required for proper regulation.

scholarly journals Glycyrrhizic Acid for COVID-19: Findings of Targeting Pivotal Inflammatory Pathways Triggered by SARS-CoV-2

2021 ◽  
Vol 12 ◽  
Author(s):  
Wenjiang Zheng ◽  
Xiufang Huang ◽  
Yanni Lai ◽  
Xiaohong Liu ◽  
Yong Jiang ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Protein Interactions ◽  
Glycyrrhizic Acid ◽  
Enrichment Analysis ◽  
Host Factors ◽  
Pathway Enrichment Analysis ◽  
Protein Protein Interactions ◽  
Health Crisis ◽  
Inflammatory Pathways ◽  
Anti Inflammatory

Background: Coronavirus disease 2019 (COVID-19) is now a worldwide public health crisis. The causative pathogen is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Novel therapeutic agents are desperately needed. Because of the frequent mutations in the virus and its ability to cause cytokine storms, targeting the viral proteins has some drawbacks. Targeting cellular factors or pivotal inflammatory pathways triggered by SARS-CoV-2 may produce a broader range of therapies. Glycyrrhizic acid (GA) might be beneficial against SARS-CoV-2 because of its anti-inflammatory and antiviral characteristics and possible ability to regulate crucial host factors. However, the mechanism underlying how GA regulates host factors remains to be determined.Methods: In our report, we conducted a bioinformatics analysis to identify possible GA targets, biological functions, protein-protein interactions, transcription-factor-gene interactions, transcription-factor-miRNA coregulatory networks, and the signaling pathways of GA against COVID-19.Results: Protein-protein interactions and network analysis showed that ICAM1, MMP9, TLR2, and SOCS3 had higher degree values, which may be key targets of GA for COVID-19. GO analysis indicated that the response to reactive oxygen species was significantly enriched. Pathway enrichment analysis showed that the IL-17, IL-6, TNF-α, IFN signals, complement system, and growth factor receptor signaling are the main pathways. The interactions of TF genes and miRNA with common targets and the activity of TFs were also recognized.Conclusions: GA may inhibit COVID-19 through its anti-oxidant, anti-viral, and anti-inflammatory effects, and its ability to activate the immune system, and targeted therapy for those pathways is a predominant strategy to inhibit the cytokine storms triggered by SARS-CoV-2 infection.

scholarly journals Luciferase-LOV BRET enables versatile and specific transcriptional readout of cellular protein-protein interactions

2019 ◽  
Author(s):  
Christina K. Kim ◽  
Kelvin F. Cho ◽  
Min Woo Kim ◽  
Alice Y. Ting
Keyword(s):  
Transcription Factor ◽  
Small Molecule ◽  
High Throughput ◽  
Protein Interactions ◽  
High Throughput Screening ◽  
Cellular Protein ◽  
Protein Protein Interactions ◽  
Lov Domain ◽  
Omics Technologies ◽  
Lower Background

Technologies that convert transient protein-protein interactions (PPIs) into stable expression of a reporter gene are useful for genetic selections, high-throughput screening, and multiplexing with omics technologies. We previously reported SPARK (Kim et al., 2017), a transcription factor that is activated by the coincidence of blue light and a PPI. Here, we report an improved, second-generation SPARK2 that incorporates a luciferase moiety to control the light-sensitive LOV domain. SPARK2 can be temporally gated by either external light or addition of a small-molecule luciferin, which causes luciferase to open LOV via proximity-dependent BRET. Furthermore, the nested “AND” gate design of SPARK2—in which both protease recruitment to the membrane-anchored transcription factor and LOV domain opening are regulated by the PPI of interest—yields a lower-background system and improved PPI specificity. We apply SPARK2 to high-throughput screening for GPCR agonists and for the detection of trans-cellular contacts, all with versatile transcriptional readout.

scholarly journals Copy number networks to guide combinatorial therapy for cancer and other disorders

2014 ◽  
Author(s):  
Andy Lin ◽  
Desmond James Smith
Keyword(s):  
Drug Treatment ◽  
Protein Interactions ◽  
Copy Number ◽  
Genetic Interaction ◽  
Single Gene ◽  
Growth Factor Receptor ◽  
Molecular Networks ◽  
Protein Protein Interactions ◽  
Gene Pairs ◽  
Cancer Networks

The dwindling drug pipeline is driving increased interest in the use of genome datasets to inform drug treatment. In particular, networks based on transcript data and protein-protein interactions have been used to design therapies that employ drug combinations. But there has been less focus on employing human genetic interaction networks constructed from copy number alterations (CNAs). These networks can be charted with sensitivity and precision by seeking gene pairs that tend to be amplified and/or deleted in tandem, even when they are located at a distance on the genome. Our experience with radiation hybrid (RH) panels, a library of cell clones that have been used for genetic mapping, have shown this tool can pinpoint statistically significant patterns of co-inherited gene pairs. In fact, we were able to identify gene pairs specifically associated with the mechanism of cell survival at single gene resolution. The strategy of seeking correlated CNAs can also be used to map survival networks for cancer. Although the cancer networks have lower resolution, the RH network can be leveraged to provide single gene specificity in the tumor networks. In a survival network for glioblastoma possessing single gene resolution, we found that the epidermal growth factor receptor (EGFR) oncogene interacted with 46 genes. Of these genes, ten (22%) happened to be targets for existing drugs. Here, we briefly review the previous use of molecular networks to design novel therapies. We then highlight the potential of using correlated CNAs to guide combinatorial drug treatment in common medical conditions. We focus on therapeutic opportunities in cancer, but also offer examples from autoimmune disorders and atherosclerosis.

scholarly journals The TCP transcription factor HvTB2 heterodimerizes with VRS5(HvTB1) and controls spike architecture in barley

2021 ◽  
Author(s):  
Tatiana de Souza Moraes ◽  
Sam W. van Es ◽  
Inmaculada Hernández-Pinzón ◽  
Gwendolyn K. Kirschner ◽  
Froukje van der Wal ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Protein Interaction ◽  
Protein Interactions ◽  
Plant Architecture ◽  
Transcriptional Regulators ◽  
Class Ii ◽  
Barley Plant ◽  
Cereal Crop ◽  
Protein Protein Interactions ◽  
Protein Protein Interaction

AbstractBarley is the fourth largest cereal crop grown worldwide, and essential for food and feed production. Phenotypically, the barley spike, which is unbranched, occurs in two main architectural shapes: two-rowed or six-rowed. In the 6-rowed cultivars, all three florets of the triple floret meristem develop into seeds while in 2-rowed lines only the central floret forms a seed. VRS5(HvTB1), act as inhibitor of lateral seed outgrowth and vrs5(hvtb1) mutants display a six-rowed spike architecture. VRS5(HvTB1) is a member of the TCP transcription factor (TF) family, which often form protein-protein interactions with other transcriptional regulators to modulate the expression of their target genes.Despite the key role of VRS5(HvTB1) in regulating barley plant architecture, there is hardly any knowledge on its molecular mode-of-action. We performed an extensive phylogenetic analysis of the TCP transcription factor family, followed by an in-vitro protein-protein interaction study using yeast-two-hybrid. Our analysis shows that VRS5(HvTB1) has a diverse interaction capacity, interacting with class II TCP’s, NF-Y TF, but also chromatin modellers. Further analysis of the interaction capacity of VRS5(HvTB1) with other TCP TFs shows that VRS5(HvTB1) preferably interacts with other class II TCP TFs within the TB1 clade. One of these interactors, encoded by HvTB2, shows a similar expression pattern when compared to VRS5(HvTB1). Haplotype analysis of HvTB2 suggest that this gene is highly conserved and shows hardly any variation in cultivars or wild barley. Induced mutations in HvTB2 trough CRISPR-CAS9 mutagenesis in cv. Golden Promise resulted in barley plants that lost their characteristic unbranched spike architecture. hvtb2 mutants exhibited branches arising at the main spike, suggesting that, similar to VRS5(HvTB1), HvTB2 act as inhibitor of branching. Taken together, our protein-protein interaction studies of VRS5(HvTB1) resulted in the identification of HvTB2, another key regulator of spike architecture in barley. Understanding the molecular network, including protein-protein interactions, of key regulators of plant architecture such as VRS5(HvTB1) provide new routes towards the identification of other key regulators of plant architecture in barley.Author summaryTranscriptional regulation is one of the basic molecular processes that drives plant growth and development. The key TCP transcriptional regulator TEOSINTE BRANCHED 1 (TB1) is one of these key regulators that has been targeted during domestication of several crops for its role as modulator of branching. Also in barley, a key cereal crop, HvTB1 (also referred to as VRS5), inhibits the outgrowth or side shoots, or tillers, and seeds. Despite its key role in barley development, there is hardly any knowledge on the molecular network that is utilized by VRS5(HvTB1). Transcriptional regulators form homo- and heterodimers to regulate the expression of their downstream targets. Here, we performed an extensive phylogenetic analysis of TCP transcription factors (TFs) in barley, followed by protein-protein interaction studies of VRS5(HvTB1). Our analysis indicates, that VRS5(HvTB1) has a diverse capacity of interacting with class II TCPs, NF-Y TF, but also chromatin modellers. Induced mutagenesis trough CRISPR-CAS mutagenesis of one of the putative VRS5(HvTB1) interactors, HvTB2, resulted in barley plants with branched spikes. This shows that insight into the VRS5(HvTB1) interactome, followed by detailed functional analysis of potential interactors is essential to truly understand how TCPs modulate plant architecture. The study presented here provides a first step to underpin the protein-protein interactome of VRS5(HvTB1) and identify other, yet unknown, key regulators of barley plant architecture.

scholarly journals A protein tertiary structure mimetic modulator of the Hippo signalling pathway

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Hélène Adihou ◽  
Ranganath Gopalakrishnan ◽  
Tim Förster ◽  
Stéphanie M. Guéret ◽  
Raphael Gasper ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Protein Interactions ◽  
Tertiary Structure ◽  
Hippo Pathway ◽  
Signalling Pathway ◽  
Protein Protein Interactions ◽  
Protein Tertiary Structure ◽  
A Cell ◽  
Chemical Modulation ◽  
Hippo Signalling

Abstract Transcription factors are key protein effectors in the regulation of gene transcription, and in many cases their activity is regulated via a complex network of protein–protein interactions (PPI). The chemical modulation of transcription factor activity is a long-standing goal in drug discovery but hampered by the difficulties associated with the targeting of PPIs, in particular when extended and flat protein interfaces are involved. Peptidomimetics have been applied to inhibit PPIs, however with variable success, as for certain interfaces the mimicry of a single secondary structure element is insufficient to obtain high binding affinities. Here, we describe the design and characterization of a stabilized protein tertiary structure that acts as an inhibitor of the interaction between the transcription factor TEAD and its co-repressor VGL4, both playing a central role in the Hippo signalling pathway. Modification of the inhibitor with a cell-penetrating entity yielded a cell-permeable proteomimetic that activates cell proliferation via regulation of the Hippo pathway, highlighting the potential of protein tertiary structure mimetics as an emerging class of PPI modulators.

scholarly journals The transcription factors Elk-1 and serum response factor interact by direct protein-protein contacts mediated by a short region of Elk-1.

1994 ◽  
Vol 14 (5) ◽  
pp. 3283-3291 ◽  
Author(s):  
P Shore ◽  
A D Sharrocks
Keyword(s):  
Transcription Factor ◽  
Transcription Factors ◽  
Protein Interactions ◽  
Serum Response Factor ◽  
Specific Protein ◽  
Response Factor ◽  
Protein Protein Interactions ◽  
Amino Acid Peptide ◽  
Necessary And Sufficient ◽  
Serum Response

Transcriptional induction of the c-fos gene in response to epidermal growth factor stimulation is mediated in part by a ternary nucleoprotein complex within the promoter consisting of serum response factor (SRF), p62TCF/Elk-1 and the serum response element (SRE). Both SRF and p62TCF/Elk-1 contact the DNA and bind in a cooperative manner to the SRE. In this study, we demonstrate that SRF and Elk-1 interact directly in the absence of the SRE. A 30-amino-acid peptide from Elk-1 (B-box) is both necessary and sufficient to mediate protein-protein contacts with SRF. Moreover, the Elk-1 B-box is necessary to enable SRF-dependent binding of an alternative ETS domain (from the transcription factor PU.1) to the c-fos SRE. Mutations in either the Elk-1 B-box or the C-terminal half of the SRF DNA-binding domain (coreSRF) which show reduced ability to form ternary complexes also show greatly reduced protein-protein interactions in the absence of the SRE. Our results clearly demonstrate that direct protein-protein interactions between the transcription factors Elk-1 and SRF, in addition to DNA contacts, contribute to the formation of a ternary complex on the c-fos SRE. We discuss the wider applicability of our results in describing specific protein-protein interactions between short well-defined transcription factor domains.

Protein Interaction Networks

2006 ◽  
Author(s):  
Soumya Raychaudhuri
Keyword(s):  
Gene Expression ◽  
Protein Interactions ◽  
Large Scale ◽  
Scientific Literature ◽  
Genetic Interaction ◽  
Genetic Interactions ◽  
Protein Protein Interactions ◽  
Expression Array ◽  
Biological Responses ◽  
Altered Gene

Genes and proteins interact with each other in many complicated ways. For example, proteins can interact directly with each other to form complexes or to modify each other so that their function is altered. Gene expression can be repressed or induced by transcription factor proteins. In addition there are countless other types of interactions. They constitute the key physiological steps in regulating or initiating biological responses. For example the binding of transcription factors to DNA triggers the assembly of the RNA assembly machinery that transcribes the mRNA that then is used as the template for protein production. Interactions such as these have been carefully elucidated and have been described in great detail in the scientific literature. Modern assays such as yeast-2-hybrid screens offer rapid means to ascertain many of the potential protein–protein interactions in an organism in a large-scale approach. In addition, other experimental modalities such as gene-expression array assays offer indirect clues about possible genetic interactions. One area that has been greatly explored in the bioinformatics literature is the possibility of learning genetic or protein networks, both from the scientific literature and from large-scale experimental data. Indeed, as we get to know more and more genes, it will become increasingly important to appreciate their interactions with each other. An understanding of the interactions between genes and proteins in a network allows for a meaningful global view of the organism and its physiology and is necessary to better understand biology. In this chapter we will explore methods to either (1) mine the scientific literature to identify documented genetic interactions and build networks of genes or (2) to confirm protein interactions that have been proposed experimentally. Our focus here is on direct physical protein–protein interactions, though the techniques described could be extended to any type of biological interaction between genes or proteins. There are multiple steps that must be addressed in identifying genetic interaction information contained within the text. After compiling the necessary documents and text, the first step is to identify gene and protein names in the text.

Identical components of yeast transcription factor IIIB are required and sufficient for transcription of TATA box-containing and TATA-less genes

1994 ◽  
Vol 14 (4) ◽  
pp. 2798-2808
Author(s):  
C A Joazeiro ◽  
G A Kassavetis ◽  
E P Geiduschek
Keyword(s):  
Transcription Factor ◽  
Protein Interactions ◽  
Rna Polymerase Iii ◽  
5S Rdna ◽  
Tata Box ◽  
Trna Genes ◽  
Small Nuclear Rna ◽  
Protein Protein Interactions ◽  
Tata Element ◽  
Transcription Factor Iiib

Specific transcription by RNA polymerase III requires recognition of the promoter-bound transcription factor IIIB (TFIIIB), of which the TATA-binding protein (TBP) is a subunit. The recruitment of TFIIIB to TATA-less genes is mediated by protein-protein interactions with transcription factor IIIC (TFIIIC) bound to the box A and box B elements. Here we examine interactions involved in the recruitment of TFIIIB to the TATA element-containing yeast U6 small nuclear RNA gene SNR6. TFIIIC is not required for the formation of TFIIIB-SNR6 gene complexes with purified components. The same three components of TFIIIB that are necessary for TFIIIC-dependent transcription of tRNA genes (recombinant TBP and Brf and the denaturing-gel-purified 90-kDa subunit) are required and sufficient for TATA box-directed U6 transcription. Despite its TFIIIC-independent, DNA sequence-dependent assembly, the TFIIIB-SNR6 complex shares important features with tDNA- and 5S rDNA-TFIIIB complexes, such as extent and location of footprint, stability, and resistance to heparin. These properties are clearly distinct from those of a TBP-SNR6 complex. In the SNR6 gene, box B, the primary binding site for TFIIIC, is suboptimally spaced relative to box A. At limiting TBP concentrations and on bare DNA, TFIIIC stimulates the formation of TFIIIB complexes with SNR6 but contributes poorly, at best, to the formation of properly placed complexes.

A PAR domain transcription factor is involved in the expression from a hematopoietic-specific promoter for the human LMO2 gene

Blood ◽  
2003 ◽  
Vol 101 (12) ◽  
pp. 4757-4764 ◽  
Author(s):  
Scott C. Crable ◽  
Kathleen P. Anderson
Keyword(s):  
Transcription Factor ◽  
Protein Interactions ◽  
Leucine Zipper ◽  
Cell Lineage ◽  
Erythroid Cell ◽  
Protein Protein Interactions ◽  
Consensus Binding Site ◽  
Basic Leucine Zipper ◽  
Specific Expression ◽  
Dna Binding Factors

AbstractThe transcription factor LMO2 is believed to exert its effect through the formation of protein-protein interactions with other DNA-binding factors such as GATA-1 and TAL1. Although LMO2 has been shown to be critical for the formation of the erythroid cell lineage, the gene is also expressed in a number of nonerythroid tissues. In this report, we demonstrate that the more distal of the 2 promoters for the LMO2 gene is highly restricted in its pattern of expression, directing the hematopoietic-specific expression of this gene. Deletion and mutation analyses have identified a critical cis element in the first untranslated exon of the gene. This element is a consensus-binding site for a small family of basic leucine zipper proteins containing a proline and acidic amino acid–rich (PAR) domain. Although all 3 members of this family are produced in erythroid cells, only 2 of these proteins, thyrotroph embryonic factor and hepatic leukemia factor, can activate transcription from this LMO2 promoter element. These findings represent a novel mechanism in erythroid gene regulation because PAR proteins have not previously been implicated in this process.

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