scholarly journals The INSL3 gene is a direct target for the orphan nuclear receptor, COUP-TFII, in Leydig cells

2014 ◽  
Vol 53 (1) ◽  
pp. 43-55 ◽  
Author(s):  
Raifish E Mendoza-Villarroel ◽  
Mickaël Di-Luoffo ◽  
Etienne Camiré ◽  
Xavier C Giner ◽  
Catherine Brousseau ◽  
...  
Keyword(s):  
Nuclear Receptor ◽  
Protein Interactions ◽  
Leydig Cells ◽  
Molecular Mechanisms ◽  
Direct Repeat ◽  
Testicular Descent ◽  
Mrna Levels ◽  
Orphan Nuclear Receptor ◽  
Protein Protein Interactions ◽  
Dna Precipitation

Insulin-like 3 (INSL3), a hormone produced by Leydig cells, regulates testicular descent during foetal life and bone metabolism in adults. Despite its importance, little is known about the molecular mechanisms controlling INSL3 expression. Reduced Insl3 mRNA levels were reported in the testis of mice deficient for chicken ovalbumin upstream promoter-transcription factor II (COUP-TFII), an orphan nuclear receptor known to play critical roles in cell differentiation and lineage determination in several tissues. Although COUP-TFII-deficient mice had Leydig cell dysfunction and impaired fertility, it remained unknown whether Insl3 expression was directly regulated by COUP-TFII. In this study, we observed a significant decrease in Insl3 mRNA levels in MA-10 Leydig cells depleted of COUP-TFII. Furthermore, a −1087 bp mouse Insl3 promoter was activated fourfold by COUP-TFII in MA-10 Leydig cells. Using 5′ progressive deletions, the COUP-TFII-responsive element was located between −186 and −79 bp, a region containing previously uncharacterised direct repeat 0-like (DR0-like) and DR3 elements. The recruitment and direct binding of COUP-TFII to the DR0-like element were confirmed by chromatin immunoprecipitation and DNA precipitation assay respectively. Mutation of the DR0-like element, which prevented COUP-TFII binding, significantly decreased COUP-TFII-mediated activation of the −1087 bp Insl3 reporter in CV-1 fibroblast cells but not in MA-10 Leydig cells. Finally, we found that COUP-TFII cooperates with the nuclear receptor steroidogenic factor 1 (SF1) to further enhance Insl3 promoter activity. Our results identify Insl3 as a target for COUP-TFII in Leydig cells and revealed that COUP-TFII acts through protein–protein interactions with other DNA-bound transcription factors, including SF1, to activate Insl3 transcription in these cells.

scholarly journals The Nuclear Receptor COUP-TFII Regulates Amhr2 Gene Transcription via a GC-Rich Promoter Element in Mouse Leydig Cells

2019 ◽  
Vol 3 (12) ◽  
pp. 2236-2257 ◽  
Author(s):  
Samir Mehanovic ◽  
Raifish E Mendoza-Villarroel ◽  
Robert S Viger ◽  
Jacques J Tremblay
Keyword(s):  
Transcription Factor ◽  
Nuclear Receptor ◽  
Leydig Cells ◽  
Mrna Levels ◽  
Gene Encoding ◽  
Conditional Deletion ◽  
Dna Precipitation ◽  
Factor Type ◽  
Novel Target

Abstract The nuclear receptor chicken ovalbumin upstream promoter–transcription factor type II (COUP-TFII)/NR2F2 is expressed in adult Leydig cells, and conditional deletion of the Coup-tfii/Nr2f2 gene impedes their differentiation. Steroid production is also reduced in COUP-TFII–depleted Leydig cells, supporting an additional role in steroidogenesis for this transcription factor. COUP-TFII action in Leydig cells remains to be fully characterized. In the present work, we report that COUP-TFII is an essential regulator of the gene encoding the anti-Müllerian hormone receptor type 2 (Amhr2), which participates in Leydig cell differentiation and steroidogenesis. We found that Amhr2 mRNA levels are reduced in COUP-TFII–depleted MA-10 Leydig cells. Consistent with this, COUP-TFII directly activates a −1486 bp fragment of the mouse Amhr2 promoter in transient transfection assays. The COUP-TFII responsive region was localized between −67 and −34 bp. Chromatin immunoprecipitation assay confirmed COUP-TFII recruitment to the proximal Amhr2 promoter whereas DNA precipitation assay revealed that COUP-TFII associates with the −67/−34 bp region in vitro. Even though the −67/−34 bp region contains an imperfect nuclear receptor element, COUP-TFII–mediated activation of the Amhr2 promoter requires a GC-rich sequence at −39 bp known to bind the specificity protein (SP)1 transcription factor. COUP-TFII transcriptionally cooperates with SP1 on the Amhr2 promoter. Mutations that altered the GCGGGGCGG sequence at −39 bp abolished COUP-TFII–mediated activation, COUP-TFII/SP1 cooperation, and reduced COUP-TFII binding to the proximal Amhr2 promoter. Our data provide a better understanding of the mechanism of COUP-TFII action in Leydig cells through the identification and regulation of the Amhr2 promoter as a novel target.

scholarly journals MEF2 Is Restricted to the Male Gonad and Regulates Expression of the Orphan Nuclear Receptor NR4A1

2014 ◽  
Vol 28 (6) ◽  
pp. 886-898 ◽  
Author(s):  
Caroline Daems ◽  
Luc J. Martin ◽  
Catherine Brousseau ◽  
Jacques J. Tremblay
Keyword(s):  
Nuclear Receptor ◽  
Leydig Cell ◽  
Leydig Cells ◽  
Sex Differentiation ◽  
Dominant Negative ◽  
Mrna Levels ◽  
Orphan Nuclear Receptor ◽  
Hormonal Stimulation ◽  
Regulatory Cascade ◽  
And Function

Abstract Leydig cell steroidogenesis is controlled by the pituitary gonadotropin LH that activates several signaling pathways, including the Ca2+/calmodulin kinase I (CAMKI) pathway. In other tissues, CAMKI regulates the activity of the myocyte enhancer factor 2 (MEF2) transcription factors. MEF2 factors are essential regulators of cell differentiation and organogenesis in numerous tissues but their expression and role in the mammalian gonad had not been explored. Here we show that MEF2 factors are expressed in a sexually dimorphic pattern in the mouse gonad. MEF2 factors are present in the testis throughout development and into adulthood but absent from the ovary. In the testis, MEF2 was localized mainly in the nucleus of both somatic lineages, the supporting Sertoli cells and the steroidogenic Leydig cells. In Leydig cells, MEF2 was found to activate the expression of Nr4a1, a nuclear receptor important for hormone-induced steroidogenesis. In these cells MEF2 also cooperates with forskolin and CAMKI to enhance Nr4a1 promoter activity via two MEF2 elements (−318 and −284 bp). EMSA confirmed direct binding of MEF2 to these elements whereas chromatin immunoprecipitation revealed that MEF2 recruitment to the proximal Nr4a1 promoter was increased following hormonal stimulation. Modulation of endogenous MEF2 protein level (small interfering RNA-mediated knockdown) or MEF2 activity (MEF2-Engrailed active dominant negative) led to a significant decrease in Nr4a1 mRNA levels in Leydig cells. All together, our results identify MEF2 as a novel testis-specific transcription factor, supporting a role for this factor in male sex differentiation and function. MEF2 was also positioned upstream of NR4A1 in a regulatory cascade controlling Leydig cell gene expression.

Structure, Function, Involvement in Diseases and Targeting of 14-3-3 Proteins: An Update

2018 ◽  
Vol 25 (1) ◽  
pp. 5-21 ◽  
Author(s):  
Ylenia Cau ◽  
Daniela Valensin ◽  
Mattia Mori ◽  
Sara Draghi ◽  
Maurizio Botta
Keyword(s):  
Protein Interactions ◽  
Molecular Mechanisms ◽  
Physiological Role ◽  
Specific Protein ◽  
Protein Protein Interactions ◽  
Cellular Processes ◽  
Protein Partners ◽  
High Sequence Homology ◽  
Small Molecule Modulators

14-3-3 is a class of proteins able to interact with a multitude of targets by establishing protein-protein interactions (PPIs). They are usually found in all eukaryotes with a conserved secondary structure and high sequence homology among species. 14-3-3 proteins are involved in many physiological and pathological cellular processes either by triggering or interfering with the activity of specific protein partners. In the last years, the scientific community has collected many evidences on the role played by seven human 14-3-3 isoforms in cancer or neurodegenerative diseases. Indeed, these proteins regulate the molecular mechanisms associated to these diseases by interacting with (i) oncogenic and (ii) pro-apoptotic proteins and (iii) with proteins involved in Parkinson and Alzheimer diseases. The discovery of small molecule modulators of 14-3-3 PPIs could facilitate complete understanding of the physiological role of these proteins, and might offer valuable therapeutic approaches for these critical pathological states.

Quantitative analysis of the interactions between HIV-1 integrase and retroviral reverse transcriptases

2008 ◽  
Vol 412 (1) ◽  
pp. 163-170 ◽  
Author(s):  
Alon Herschhorn ◽  
Iris Oz-Gleenberg ◽  
Amnon Hizi
Keyword(s):  
Conformational Changes ◽  
Protein Interactions ◽  
Molecular Mechanisms ◽  
Reaction Model ◽  
Protein Protein Interactions ◽  
Common Site ◽  
Leukaemia Virus ◽  
Reverse Transcriptases ◽  
Interaction Kinetics ◽  
Hiv 1

The RT (reverse transcriptase) of HIV-1 interacts with HIV-1 IN (integrase) and inhibits its enzymatic activities. However, the molecular mechanisms underling these interactions are not well understood. In order to study these mechanisms, we have analysed the interactions of HIV-1 IN with HIV-1 RT and with two other related RTs: those of HIV-2 and MLV (murine-leukaemia virus). All three RTs inhibited HIV-1 IN, albeit to a different extent, suggesting a common site of binding that could be slightly modified for each one of the studied RTs. Using surface plasmon resonance technology, which monitors direct protein–protein interactions, we performed kinetic analyses of the binding of HIV-1 IN to these three RTs and observed interesting binding patterns. The interaction of HIV-1 RT with HIV-1 IN was unique and followed a two-state reaction model. According to this model, the initial IN–RT complex formation was followed by a conformational change in the complex that led to an elevation of the total affinity between these two proteins. In contrast, HIV-2 and MLV RTs interacted with IN in a simple bi-molecular manner, without any apparent secondary conformational changes. Interestingly, HIV-1 and HIV-2 RTs were the most efficient inhibitors of HIV-1 IN activity, whereas HIV-1 and MLV RTs showed the highest affinity towards HIV-1 IN. These modes of direct protein interactions, along with the apparent rate constants calculated and the correlations of the interaction kinetics with the capacity of the RTs to inhibit IN activities, are all discussed.

scholarly journals Significance of thiol-disulfide balance in SARS-CoV-2 infection

2021 ◽  
Vol 72 (3) ◽  
pp. 30-36
Author(s):  
Tatjana Simić
Keyword(s):  
Cell Surface ◽  
Host Cell ◽  
Protein Interactions ◽  
Viral Entry ◽  
Molecular Mechanisms ◽  
Alkylating Agents ◽  
Protein S ◽  
Protein Protein Interactions ◽  
Virus Surface ◽  
Host Cell Surface

Studies of the molecular mechanisms regarding interaction of different viruses with receptors on the host cell surface have shown that the viral entry depends on the specific relationship between free thiol (SH) groups and disulfides on the virus surface, as well as the thiol disulfide balance on the host cell surface. The presence of oxidizing compounds or alkylating agents, which disturb the thiol-disulfide balance on the surface of the virus, can also affect its infectious potential. Disturbed thiol-disulfide balance may also influence protein-protein interactions between SARS-CoV-2 protein S and ACE2 receptors of the host cell. This review presents the basic mechanisms of maintaining intracellular and extracellular thiol disulfide balance and previous experimental and clinical evidence in favor of impaired balance in SARS-CoV-2 infection. Besides, the results of the clinical application or experimental analysis of compounds that induce changes in the thiol disulfide balance towards reduction of disulfide bridges in proteins of interest in COVID-19 infection are presented.

LH Induces Orphan Nuclear Receptor Nur77 Gene Expression in Testicular Leydig Cells

Endocrinology ◽  
2001 ◽  
Vol 142 (12) ◽  
pp. 5116-5123 ◽  
Author(s):  
Kwang-Hoon Song ◽  
Jae-Il Park ◽  
Mi-Ock Lee ◽  
Jaemog Soh ◽  
Keesook Lee ◽  
...  
Keyword(s):  
Gene Expression ◽  
Nuclear Receptor ◽  
Leydig Cells ◽  
Orphan Nuclear Receptor

Cytokine-induced changes in chromatin structure and in vivo footprints in the inducible NOS promoter

2001 ◽  
Vol 280 (3) ◽  
pp. L390-L399 ◽  
Author(s):  
Jane K. Mellott ◽  
Harry S. Nick ◽  
Michael F. Waters ◽  
Timothy R. Billiar ◽  
David A. Geller ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Protein Interactions ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Specific Pattern ◽  
Mrna Levels ◽  
Inos Gene ◽  
In Vivo Footprinting ◽  
Induced Changes

Transcription of the human inducible nitric oxide synthase ( iNOS) gene is regulated by inflammatory cytokines in a tissue-specific manner. To determine whether differences in cytokine-induced mRNA levels between pulmonary epithelial cells (A549) and hepatic biliary epithelial cells (AKN-1) result from different protein or DNA regulatory mechanisms, we identified cytokine-induced changes in DNase I-hypersensitive (HS) sites in 13 kb of the iNOS 5′-flanking region. Data showed both constitutive and inducible HS sites in an overlapping yet cell type-specific pattern. Using in vivo footprinting and ligation-mediated PCR to detect potential DNA or protein interactions, we examined one promoter region near −5 kb containing both constitutive and cytokine-induced HS sites. In both cell types, three in vivo footprints were present in both control and cytokine-treated cells, and each mapped within a constitutive HS site. The remaining footprint appeared only in response to cytokine treatment and mapped to an inducible HS site. These studies, performed on chromatin in situ, identify a portion of the molecular mechanisms regulating transcription of the human iNOS gene in both lung- and liver-derived epithelial cells.

scholarly journals Search for New Candidate Genes Involved in the Comorbidity of Asthma and Hypertension Based on Automatic Analysis of Scientific Literature

2018 ◽  
Vol 15 (4) ◽  
Author(s):  
Olga V. Saik ◽  
Pavel S. Demenkov ◽  
Timofey V. Ivanisenko ◽  
Elena Yu. Bragina ◽  
Maxim B. Freidin ◽  
...  
Keyword(s):  
Protein Interactions ◽  
Gene Networks ◽  
Molecular Mechanisms ◽  
Molecular Genetic ◽  
Genetic Networks ◽  
Positive Sign ◽  
Phenotypic Traits ◽  
Protein Protein Interactions ◽  
Scientific Publications ◽  
Associative Gene Networks

AbstractComorbid states of diseases significantly complicate diagnosis and treatment. Molecular mechanisms of comorbid states of asthma and hypertension are still poorly understood. Prioritization is a way for identifying genes involved in complex phenotypic traits. Existing methods of prioritization consider genetic, expression and evolutionary data, molecular-genetic networks and other. In the case of molecular-genetic networks, as a rule, protein-protein interactions and KEGG networks are used. ANDSystem allows reconstructing associative gene networks, which include more than 20 types of interactions, including protein-protein interactions, expression regulation, transport, catalysis, etc. In this work, a set of genes has been prioritized to find genes potentially involved in asthma and hypertension comorbidity. The prioritization was carried out using well-known methods (ToppGene and Endeavor) and a cross-talk centrality criterion, calculated by analysis of associative gene networks from ANDSystem. The identified genes, including IL1A, CD40LG, STAT3, IL15, FAS, APP, TLR2, C3, IL13 and CXCL10, may be involved in the molecular mechanisms of comorbid asthma/hypertension. An analysis of the dynamics of the frequency of mentioning the most priority genes in scientific publications revealed that the top 100 priority genes are significantly enriched with genes with increased positive dynamics, which may be a positive sign for further studies of these genes.

Bioinformatics studies on structures, functions and diversifications of rolling leaf related genes in rice (Oryza sativa L.)

2020 ◽  
pp. 1-14
Author(s):  
Md. Jahangir Alam ◽  
Md. Alamin ◽  
Most. Humaira Sultana ◽  
Md. Asif Ahsan ◽  
Md. Ripter Hossain ◽  
...  
Keyword(s):  
Protein Interactions ◽  
Molecular Mechanisms ◽  
Oryza Sativa L ◽  
Vital Role ◽  
High Yield ◽  
Leaf Rolling ◽  
Protein Protein Interactions ◽  
Conserved Domains ◽  
Kegg Pathways ◽  
Conserved Domain

Abstract Leaf morphology of crop plants has significant value in agronomy. Leaf rolling in rice plays a vital role to increase grain yield. However, collective information on the rolling leaf (RL) genes reported to date and different comparative bioinformatics studies of their sequences are still incomplete. This bioinformatics study was designed to investigate structures, functions and diversifications of the RL related genes reported till now through several studies. We performed different comparative and functional analyses of the selected 42 RL genes among 103 RL genes using different bioinformatics techniques including gene structure, conserved domain, phylogenetic, gene ontology (GO), transcription factor (TF), Kyoto Encyclopedia of Genes and Genomes (KEGG) and protein–protein network. Exon-intron organization and conserved domain analysis showed diversity in structures and conserved domains of RL genes. Phylogenetic analysis classified the proteins into five major groups. GO and TF analyses revealed that regulation-related genes were remarkably enriched in biological process and 10 different TF families were involved in rice leaf rolling. KEGG analysis demonstrated that 14 RL genes were involved in the KEGG pathways, among which 50% were involved in the metabolism pathways. Of the selected RL proteins, 55% proteins were non-interacting with other RL proteins and OsRL9 was the most interacting RL protein. These results provide important information regarding structures, conserved domains, phylogenetic revolution, protein–protein interactions and other genetic bases of RL genes which might be helpful to the researchers for functional analysis of new candidate RL genes to explore their characteristics and molecular mechanisms for high yield rice breeding.

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