Diana Stavreva
National Institutes of Health, NCI, Department Member
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Mechanotransduction is the ability of a cell to sense mechanical cues from its microenvironment and convert them into biochemical signals to elicit adaptive transcriptional and other cellular responses. Here, we describe recent advances... more
Mechanotransduction is the ability of a cell to sense mechanical cues from its microenvironment and convert them into biochemical signals to elicit adaptive transcriptional and other cellular responses. Here, we describe recent advances in the field of mechanical regulation of transcription, highlight mechanical regulation of the epigenome as a key novel aspect of mechanotransduction, and describe recent technological advances that could further elucidate the link between mechanical stimuli and gene expression. In this review, we emphasize the importance of mechanotransduction as one of the governing principles of cancer progression, underscoring the need to conduct further studies of the molecular mechanisms involved in sensing mechanical cues and coordinating transcriptional responses.
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Representative datasets associated with article "Transcriptional Bursting and Co-bursting Regulation by Steroid Hormone Release Pattern and Transcription Factor Mobility."
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Sex hormones, such as androgens, estrogens and progestins are naturally occurring compounds that tightly regulate endocrine systems in a variety of living organisms. Uncontrolled environmental exposure to these hormones or their... more
Sex hormones, such as androgens, estrogens and progestins are naturally occurring compounds that tightly regulate endocrine systems in a variety of living organisms. Uncontrolled environmental exposure to these hormones or their biological and synthetic mimetics has been widely documented. Furthermore, water contaminants penetrate soil to affect flora, fauna and ultimately humans. Because endocrine systems evolved to respond to very small changes in hormone levels, the low levels found in the environment cannot be ignored. The combined actions of sex hormones with glucocorticoids and other nuclear receptors disruptors creates additional level of complexity including the newly described "dynamic assisted loading" mechanism. We reviewed the extensive literature pertaining to world-wide detection of these disruptors and created a detailed Table on the development and current status of methods used for their analysis.
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Research Interests: Molecular Biology, Kinetics, Biology, Gamma Rays, DNA damage, and 15 moreDNA repair, Medicine, Environmental Biotechnology, DNA, Mutation, Comet Assay, Nicotiana Tabacum, Radiation Dose, Irradiation, Ionizing Radiation, Gamma Irradiation, Gamma radiation, Somatic Cells, Plant Leaf, and Pharmacology and pharmaceutical sciences
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Research Interests: Biology, Cell Biology, Biological Sciences, Cell line, Environmental Sciences, and 15 moreHumans, Animals, Alternative splicing, Cell nucleus, Chickens, Heat Shock, Alternative Splicing, Heat Shock Protein, Base Sequence, Cytoplasm, DNA binding proteins, Full Length Movies, Cysteine Proteinase Inhibitors, acetylcysteine, and Distribution Pattern
Research Interests: Cellular Biology, Fluorescence Microscopy, Biology, Cell Biology, Medicine, and 15 moreBiological Sciences, Ubiquitin, Cell line, Molecular and cellular biology, Humans, Proteasome, Biogenesis, Immunoprecipitation, Ribosome, Ribosome biogenesis, Ubiquitin Proteasome System, Nucleolus, Ribosomes, Dynamic Properties, and Medical and Health Sciences
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Research Interests: Chemistry, Biology, Biological Chemistry, Medicine, Biological Sciences, and 15 moreCell line, Humans, Sequence alignment, Mutation, Animals, HIstone Deacetylase, Biological, CHEMICAL SCIENCES, HDAC, Acetylation, Amino Acid Sequence, Histone, Glucocorticoid Receptors, Molecular Sequence Data, and Medical and Health Sciences
Research Interests: Algorithms, Biophysics, Biology, Medicine, Parameter estimation, and 15 moreBiological Sciences, Computer Simulation, Mice, Animals, Physical sciences, Cluster Analysis, Photobleaching, CHEMICAL SCIENCES, Cell nucleus, Protein Binding, Protein Localization, Binding Site, Adenocarcinoma, Mouse Mammary Tumor Virus, and binding sites
Cells must tightly regulate their gene expression programs and yet rapidly respond to acute biochemical and biophysical cues within their environment. This information is transmitted to the nucleus through various signaling cascades,... more
Cells must tightly regulate their gene expression programs and yet rapidly respond to acute biochemical and biophysical cues within their environment. This information is transmitted to the nucleus through various signaling cascades, culminating in the activation or repression of target genes. Transcription factors (TFs) are key mediators of these signals, binding to specific regulatory elements within chromatin. While live-cell imaging has conclusively proven that TF–chromatin interactions are highly dynamic, how such transient interactions can have long-term impacts on developmental trajectories and disease progression is still largely unclear. In this review, we summarize our current understanding of the dynamic nature of TF functions, starting with a historical overview of early live-cell experiments. We highlight key factors that govern TF dynamics and how TF dynamics, in turn, affect downstream transcriptional bursting. Finally, we conclude with open challenges and emerging technologies that will further our understanding of transcriptional regulation. Expected final online publication date for the Annual Review of Cell and Developmental Biology, Volume 39 is October 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Photobleaching technology has demonstrated in live cells that the glucocorticoid receptor (GR) exchanges rapidly at the mouse mammary tumor virus (MMTV) promoter. GR rapid exchange at MMTV depends on chaperone and proteasome activity, and... more
Photobleaching technology has demonstrated in live cells that the glucocorticoid receptor (GR) exchanges rapidly at the mouse mammary tumor virus (MMTV) promoter. GR rapid exchange at MMTV depends on chaperone and proteasome activity, and as suggested by several in vitro and in vivo biochemical approaches, may also involve chromatin remodeling activity. Inhibition of H1 phosphorylation, chromatin remodeling and transcription from MMTV can be accomplished by long-term blocking of Cdk2 protein kinase activity. We find that Cdk2 is recruited by a tandem array of MMTV promoters, strengthening the model that this kinase has a specific role in MMTV transcription. We also demonstrate that following a brief Cdk2 inhibition by a selective cyclin-dependent kinase inhibitor (Roscovitine), transcription from MMTV drops and GR exchange at MMTV becomes slower, with a fraction of GR molecules now tightly bound at the promoter. This immobile fraction is absent elsewhere in the nucleus, suggesting a specific effect of Cdk2 inhibition on GR-MMTV interactions. These are the first live cell data suggesting a role for H1 phosphorylation, and by implication chromatin remodeling, in rapid exchange of GR at MMTV.
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Research Interests: Kinetics, Genetic Toxicology, Biology, Gamma Rays, DNA damage, and 15 moreDNA repair, Medicine, Environmental Biotechnology, Cell Division, DNA, Mutation, Enzyme, Comet Assay, Cell nucleus, Nicotiana Tabacum, Electrophoresis, Ionizing Radiation, Mutagens, Cell Suspension Culture, and Pharmacology and pharmaceutical sciences
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Introduction: Some natural and anthropogenic substances in drinking water sources are known or suspected endocrine disrupting chemicals (EDC), but few are measured in U.S. public water supplies (PW...
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ABSTRACT Fluorescence recovery after photobleaching (FRAP) is an optical technique used to measure the temporal dynamics of fluorescently tagged molecules. FRAP is a relatively old technique. This renaissance is driven largely by the... more
ABSTRACT Fluorescence recovery after photobleaching (FRAP) is an optical technique used to measure the temporal dynamics of fluorescently tagged molecules. FRAP is a relatively old technique. This renaissance is driven largely by the advent of confocal microscopy and the introduction of green fluorescent protein (GFP) as an endogenous protein marker. After GFP (or another fluorophore) is covalently attached to the protein of interest, its cellular distribution can be visualized at low light intensities that do not damage cellular processes. Photobleaching is the irreversible destruction of fluorescence in a region within the sample by brief exposure to high light intensities. After bleaching a region, the recovery of fluorescence over time there can be recorded to measure the rate of redistribution of fluorescent molecules. This rate of fluorescence redistribution provides information about the processes involved in the movement of the molecule. The movement reflects diffusion, which can be retarded if the fluorescently tagged molecule binds to other molecules. In the latter case, the rate of redistribution of bleached and unbleached molecules contain information about the strength of the binding interaction. Thus, FRAP is a valuable technique to study molecular dynamics in live cells.
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Research Interests: Biology, Tobacco, Medicinal Plants, DNA damage, Medicine, and 15 moreDNA, Mutagenesis, Mutation, Plant Roots, Herbicides, Comet Assay, Nicotiana Tabacum, Vicia faba, Fabaceae, Time Factors, Hydrogen-Ion Concentration, Plant Leaves, Chromatids, Chromosome aberrations, and Pharmacology and pharmaceutical sciences
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A large variety of mechanisms are utilized in the regulation of gene expression by the glucocorticoid receptor. The receptor is subject to complex subcellular-trafficking processes that modulate the distribution of the receptor in living... more
A large variety of mechanisms are utilized in the regulation of gene expression by the glucocorticoid receptor. The receptor is subject to complex subcellular-trafficking processes that modulate the distribution of the receptor in living cells. Although DNA sequence is the primary recognition element in genome regulatory sites, access of the receptor to these sites is strongly modulated by chromatin structure, and the subsequent reorganization of local nucleoprotein domains is a key component of receptor function. The receptor-response elements can be located at large distances from gene targets, indicating that long-range interactions within the nuclear architecture contribute to receptor action. Furthermore, the receptor is subject to many post-translational modifications, and these alterations can affect receptor function at several levels. Finally, interactions between receptors and the genome are surprisingly rapid, indicating a dynamic aspect of receptor movement only recently appreciated.
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How chromatin dynamics relate to transcriptional activity remains poorly understood. Using single-molecule tracking, coupled with machine learning, we show that histone H2B and multiple chromatin-bound transcriptional regulators display... more
How chromatin dynamics relate to transcriptional activity remains poorly understood. Using single-molecule tracking, coupled with machine learning, we show that histone H2B and multiple chromatin-bound transcriptional regulators display two distinct low-mobility states. Ligand activation results in a marked increase in the propensity of steroid receptors to bind in the lowest-mobility state. Mutational analysis revealed that interactions with chromatin in the lowest-mobility state require an intact DNA binding domain and oligomerization domains. These states are not spatially separated as previously believed, but individual H2B and bound-TF molecules can dynamically switch between them on time scales of seconds. Single bound-TF molecules with different mobilities exhibit different dwell time distributions, suggesting that the mobility of TFs is intimately coupled with their binding dynamics. Together, our results identify two unique and distinct low-mobility states that appear to re...
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Current data using gene expression and DNA modification profiles yield limited information for evaluating the potential resistance to therapies. Recent studies show that the chromatin landscape is dynamic and defines cell identity and... more
Current data using gene expression and DNA modification profiles yield limited information for evaluating the potential resistance to therapies. Recent studies show that the chromatin landscape is dynamic and defines cell identity and disease status. Thus, changes in open chromatin sites could provide important information on disease progression and identify potential therapeutic targets. The majority of breast cancers express estrogen receptor (ER) and initially respond to endocrine therapies blocking ER activity. However, endocrine therapy resistance (ETR) occurs de novo or follows an initial response. Recent studies have identified new drivers of ETR, such as mTOR and CDK4/6. Therapy with these inhibitors in combination with endocrine therapy have improved patient survival, but the molecular mechanism of ETR is not fully understood and additional therapeutic options for ETR are needed. To investigate the molecular mechanisms of ETR, we established in vitro Long-Term Estrogen Depr...
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ABSTRACTHow transcription factors (TFs) navigate the complex nuclear environment to assemble the transcriptional machinery at specific genomic loci remains elusive. Using single-molecule tracking, coupled with machine learning, we... more
ABSTRACTHow transcription factors (TFs) navigate the complex nuclear environment to assemble the transcriptional machinery at specific genomic loci remains elusive. Using single-molecule tracking, coupled with machine learning, we examined the mobility of multiple transcriptional regulators. We show that H2B and ten different transcriptional regulators display two distinct low-mobility states. Our results indicate that both states represent dynamic interactions with chromatin. Ligand activation results in a dramatic increase in the proportion of steroid receptors in the lowest mobility state. Mutational analysis revealed that only chromatin interactions in the lowest mobility state require an intact DNA-binding domain as well as oligomerization domains. Importantly, these states are not spatially separated as previously believed but in fact, individual H2B and TF molecules can dynamically switch between them. Together, our results identify two unique and distinct low-mobility states...
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The cohesin complex is central to chromatin looping, but mechanisms by which these long-range chromatin interactions are formed and persist remain unclear. We demonstrate that interactions between a transcription factor (TF) and the... more
The cohesin complex is central to chromatin looping, but mechanisms by which these long-range chromatin interactions are formed and persist remain unclear. We demonstrate that interactions between a transcription factor (TF) and the cohesin loader NIPBL regulate enhancer-dependent gene activity. Using mass spectrometry, genome mapping, and single-molecule tracking methods, we demonstrate that the glucocorticoid (GC) receptor (GR) interacts with NIPBL and the cohesin complex at the chromatin level, promoting loop extrusion and long-range gene regulation. Real-time single-molecule experiments show that loss of cohesin markedly diminishes the concentration of TF molecules at specific nuclear confinement sites, increasing TF local concentration and promoting gene regulation. Last, patient-derived acute myeloid leukemia cells harboring cohesin mutations exhibit a reduced response to GCs, suggesting that the GR-NIPBL-cohesin interaction is defective in these patients, resulting in poor re...
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Research Interests: Biology, Biological Chemistry, Transcription Factors, Medicine, Biological Sciences, and 13 moreMice, Animals, HIstone Deacetylase, Biological, Transcription Factor, CHEMICAL SCIENCES, HDAC, Acetylation, Histone, fluorescence recovery after photobleaching (FRAP), Glucocorticoid Receptors, Adenocarcinoma, and Medical and Health Sciences
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The presence of progesterone receptor (PR)-interacting compounds in the environment may have serious health consequences for humans and wildlife, but the methods for their detection and monitoring are limited. Here we report the... more
The presence of progesterone receptor (PR)-interacting compounds in the environment may have serious health consequences for humans and wildlife, but the methods for their detection and monitoring are limited. Here we report the development and testing of a cell line expressing a chimeric construct containing ligand-binding domain of progesterone receptor and green fluorescent protein-tagged domain of the glucocorticoid receptor (GFP-GR-PR) under tetracycline regulation. Unlike the constitutively nuclear PR, this chimera is cytoplasmic in the absence of the ligand and translocates to the nucleus in response to the hormone or its analogues. The GFP-GR-PR chimera maintains specificity for binding to progesterone and does not cross-react with GR-activating hormones. A concentration- and time-dependent translocation in response to progesterone confirmed picomolar sensitivity for detecting PR ligands. Importantly, the assay can detect both agonist and antagonist activities and thus can b...
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Cette invention concerne des compositions, des procedes, un systeme et des kits pour detecter les produits chimiques qui sont des perturbateurs endocriniens (EDC) dans des echantillons environnementaux et autres, tels que des echantillons... more
Cette invention concerne des compositions, des procedes, un systeme et des kits pour detecter les produits chimiques qui sont des perturbateurs endocriniens (EDC) dans des echantillons environnementaux et autres, tels que des echantillons d'eau comprenant, entre autres, des effluents d'usines de traitement d'eaux usees, a l'aide d'un systeme rapporteur de translocation nucleaire de la fluorescence dans des cellules vivantes. Apres liaison d'un ligand a une proteine rapporteur marquee par fluorescence, la proteine (et par consequent, la fluorescence) subit une translocation de type niveau de ligand-dependante, du cytoplasme vers le noyau de cellules de mammiferes vivantes, ladite translocation etant detectable par conversion de la fluorescence diffuse dans le cytoplasme en une forte fluorescence, localisee dans les noyaux. Les procedes, les kits et le systeme selon l'invention peuvent etre utilises pour detecter de maniere fiable de tres bas niveaux de con...
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The medium recovered from the tobacco cell suspension cultures (TX1MX) activated the promutagenic aromatic amine m-phenylenediamine (mPDA) and a macromolecular complex (gel) responsible for the arylamine activation was isolated from the... more
The medium recovered from the tobacco cell suspension cultures (TX1MX) activated the promutagenic aromatic amine m-phenylenediamine (mPDA) and a macromolecular complex (gel) responsible for the arylamine activation was isolated from the medium. The gel formation and the role of the gel components in the plant activation of mPDA to products mutagenic in S. typhimurium YG1024 were studied. The activation of mPDA was caused by the peroxidases present in TX1MX. We demonstrated an association of the peroxidase activity and gel pectins. Formation of a stable mutagenic association of mPDA with the macromolecular material was observed. The data indicate that the gel isolated from TX1MX is the macromolecular component of the arylamine conjugate proposed in earlier work.
Research Interests: Chemistry, Medicine, Extracellular Matrix, Cell Culture, Cell Division, and 15 morePeroxidase, Mutation, Salmonella Typhimurium, Potassium, Gels, Macromolecule, Peroxidases, Biotransformation, Molecular Mechanisms, Pectins, Mutagens, PLANT PROTEINS, Cell Suspension Culture, Mutagenicity tests, and Cell culture techniques
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Contamination of the environment with endocrine disrupting chemicals (EDCs) is a major health concern. The presence of estrogenic compounds in water and their deleterious effect are well documented. However, detection and monitoring of... more
Contamination of the environment with endocrine disrupting chemicals (EDCs) is a major health concern. The presence of estrogenic compounds in water and their deleterious effect are well documented. However, detection and monitoring of other classes of EDCs is limited. Here we utilize a high-throughput live cell assay based on sub-cellular relocalization of GFP-tagged glucocorticoid and androgen receptors (GFP-GR and GFP-AR), in combination with gene transcription analysis, to screen for glucocorticoid and androgen activity in water samples. We report previously unrecognized glucocorticoid activity in 27%, and androgen activity in 35% of tested water sources from 14 states in the US. Steroids of both classes impact body development, metabolism, and interfere with reproductive, endocrine, and immune systems. This prevalent contamination could negatively affect wildlife and human populations.
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These continuously varying response profiles could arise by a variety of mechanisms. We have discovered that nuclear receptors interact dynamically with regulatory elements in living cells 3 , and have proposed the... more
These continuously varying response profiles could arise by a variety of mechanisms. We have discovered that nuclear receptors interact dynamically with regulatory elements in living cells 3 , and have proposed the 'hit and run' hypothesis for receptor function 1,2,4 . Under this ...
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A leading figure in the field of plant genetics RNDr. Tomas Gichner, DrSc. passed away on 6th January 2019 at the age of 83.