Similar Datasets
Project description:Enhancers serve as the major activators of mammalian signal-dependent transcriptional programs, exemplified by responses to liganded nuclear receptors, where their acute initial activation, is characterized by alternating periods of target gene “bursting” and “non-busting”, followed by a protracted chronic period of diminished transcriptional activation. Linking these responses to alterations in induced enhancer condensates and locus motility in real time would provide insights into these dynamic regulatory events. Here, endogenous live cell imaging reveals the altered chromosomal dynamics during estrogen receptor (ER)-dependent target gene bursting/post-bursting and chronic activation events. We first observed that acute stimulation of ER results in increased frequency of bursting compared to the unstimulated state, but bursting actually diminishes with prolonged, chronic E2 stimulation. Second, while acute ligand-dependent activation results in higher levels of mobility of the chromosomal locus than in the unstimulated condition, this mobility further increases during chronic E2 stimulation. Simultaneous DNA/RNA endogenous live imaging of enhancer regulated target gene transcription revealed that the increased mobility of acutely ER-stimulated loci observed during the bursting phase was, unexpectedly, further increased in the subsequent non-burst phase, revealing that the transcription burst event is not the mechanism underlying increased motility. Single molecule tracking (SMT) of ER showed that the relatively high-burst, lower-mobility acute state was indeed enriched for high-viscosity, 1,6-hexanediol-sensative ER molecules. Interestingly, the increased proximity of E2-stimulated loci to interchromatin granules remained unchanged between the bursting and non-bursting phases of acute activation. Together these findings support a dynamic, multi-state condensate model for enhancer-regulated transcriptional programs.
2026-01-01 | GSE221898 | GEO
Project description:Enhancers serve as the major activators of mammalian signal-dependent transcriptional programs, exemplified by responses to liganded nuclear receptors, where their acute initial activation, is characterized by alternating periods of target gene “bursting” and “non-busting”, followed by a protracted chronic period of diminished transcriptional activation. Linking these responses to alterations in induced enhancer condensates and locus motility in real time would provide insights into these dynamic regulatory events. Here, endogenous live cell imaging reveals the altered chromosomal dynamics during estrogen receptor (ER)-dependent target gene bursting/post-bursting and chronic activation events. We first observed that acute stimulation of ER results in increased frequency of bursting compared to the unstimulated state, but bursting actually diminishes with prolonged, chronic E2 stimulation. Second, while acute ligand-dependent activation results in higher levels of mobility of the chromosomal locus than in the unstimulated condition, this mobility further increases during chronic E2 stimulation. Simultaneous DNA/RNA endogenous live imaging of enhancer regulated target gene transcription revealed that the increased mobility of acutely ER-stimulated loci observed during the bursting phase was, unexpectedly, further increased in the subsequent non-burst phase, revealing that the transcription burst event is not the mechanism underlying increased motility. Single molecule tracking (SMT) of ER showed that the relatively high-burst, lower-mobility acute state was indeed enriched for high-viscosity, 1,6-hexanediol-sensative ER molecules. Interestingly, the increased proximity of E2-stimulated loci to interchromatin granules remained unchanged between the bursting and non-bursting phases of acute activation. Together these findings support a dynamic, multi-state condensate model for enhancer-regulated transcriptional programs.
2026-01-01 | GSE221897 | GEO
Project description:Endogenous Real Time Imaging Reveals Dynamic Chromosomal Mobility During ER-Mediated Transcriptional Burst Events
| PRJNA916680 | ENA
Project description:Endogenous Real Time Imaging Reveals Dynamic Chromosomal Mobility During ER-Mediated Transcriptional Burst Events [ChIP-seq]
| PRJNA916709 | ENA
Project description:Endogenous Real Time Imaging Reveals Dynamic Chromosomal Mobility During ER-Mediated Transcriptional Burst Events [PRO-seq]
| PRJNA916708 | ENA
Project description:The distribution of viruses and gene therapy vectors is difficult to assess in a living organism. For instance, trafficking in murine models can usually only be assessed after sacrificing the animal for tissue sectioning or extraction. These assays are laborious requiring whole animal sectioning to ascertain tissue localization. They also obviate the ability to perform longitudinal or kinetic studies in one animal. To track viruses after systemic infection, we have labeled adenoviruses with a near-infrared (NIR) fluorophore and imaged these after intravenous injection in mice. Imaging was able to track and quantitate virus particles entering the jugular vein simultaneous with injection, appearing in the heart within 500 milliseconds, distributing in the bloodstream and throughout the animal within 7 seconds, and that the bulk of virus distribution was essentially complete within 3 minutes. These data provide the first in vivo real-time tracking of the rapid initial events of systemic virus infection.
| S-EPMC3039657 | biostudies-literature
Project description:Imaging through dynamic scattering media is one of the most challenging yet fascinating problems in optics, with applications spanning from biological detection to remote sensing. In this study, we propose a comprehensive learning-based technique that facilitates real-time, non-invasive, incoherent imaging of real-world objects through dense and dynamic scattering media. We conduct extensive experiments, demonstrating the capability of our technique to see through turbid water and natural fog. The experimental results indicate that the proposed technique surpasses existing approaches in numerous aspects and holds significant potential for imaging applications across a broad spectrum of disciplines.
| S-EPMC11329739 | biostudies-literature
Project description:We directly resolved discrete exocytic fusion events mediating insertion of AMPA-type glutamate receptors (AMPARs) to the somatodendritic surface of rat hippocampal pyramidal neurons, in slice and dissociated cultures, using protein tagging with a pH-sensitive GFP (green fluorescent protein) variant and rapid (10 frames/s) fluorescence microscopy. AMPAR-containing exocytic events occurred under basal culture conditions in both the cell body and dendrites; potentiating chemical stimuli produced an NMDA receptor-dependent increase in the frequency of individual exocytic events. The number of AMPARs inserted per exocytic event, estimated using single-molecule analysis, was quite uniform but individual events differed significantly in kinetic properties affecting the subsequent surface distribution of receptors. "Transient" events, from which AMPARs dispersed laterally immediately after surface insertion, generated a pronounced but short-lived (dissipating within approximately 1 s) increase in surface AMPAR fluorescence extending locally (2-5 microm) from the site of exocytosis. "Persistent" events, from which inserted AMPARs dispersed slowly (typically over 5-10 s), affected local surface receptor concentration to a much smaller degree. Both modes of exocytic insertion occurred throughout the dendritic shaft, but remarkably, neither mode of insertion was observed directly into synaptic spines. AMPARs entered spines preferentially from transient events occurring in the adjoining dendritic shaft, driven apparently by mass action and short-range lateral diffusion, and locally delivered AMPARs remained mostly in the mobile fraction. These results suggest a highly dynamic mechanism for both constitutive and activity-dependent surface delivery of AMPARs, mediated by kinetically distinct exocytic modes that differ in propensity to drive lateral entry of receptors to nearby synapses.
| S-EPMC3249441 | biostudies-literature
Project description:Endoplasmic reticulum (ER) degradation by autophagy (ER-phagy) is a recently revealed selective autophagy pathway that plays important roles in organelle turnover and protein degradation, but the biological functions of ER-phagy are largely unknown. Here, we present an ER-targeting Re(I) tricarbonyl complex (Re-ERLAD) that can accumulate in the ER, induce ER-to-lysosome-associated degradation (ERLAD) upon visible light irradiation, and label ER buds and track their morphological alterations during ER-phagy. The emission of Re-ERLAD is sensitive to viscosity, which is a key parameter reflecting the amount of unfolded protein in the ER. Quantitative detection using two-photon fluorescence lifetime imaging microscopy shows that ER viscosity initially increases and then decreases during ERLAD, which reveals that ERLAD is a pathway for alleviating ER stress caused by unfolded proteins. In conclusion, our work presents the first specific photoinducer and tracker of ERLAD, which can be used in studying the regulatory mechanism and function of this process.
| S-EPMC9362766 | biostudies-literature
Project description:Hyperspectral imaging has tremendous potential to detect important molecular biomarkers of early cancer based on their unique spectral signatures. Several drawbacks have limited its use for in vivo screening applications: most notably the poor temporal and spatial resolution, high expense, and low optical throughput of existing hyperspectral imagers. We present the development of a new real-time hyperspectral endoscope (called the image mapping spectroscopy endoscope) based on an image mapping technique capable of addressing these challenges. The parallel high throughput nature of this technique enables the device to operate at frame rates of 5.2 frames per second while collecting a (x, y, λ) datacube of 350 × 350 × 48. We have successfully imaged tissue in vivo, resolving a vasculature pattern of the lower lip while simultaneously detecting oxy-hemoglobin.
| S-EPMC3107836 | biostudies-other