Cellular imaging

  • Article
    | Open Access

    Calcium signals initiated by IP3 receptors in ER membranes regulate most cellular activities. Here, the authors show that KRas-induced actininteracting protein (KRAP) tethers a small subset of IP3 receptors to actin and licenses them to evoke cytosolic calcium signals.

    • Nagendra Babu Thillaiappan
    • , Holly A. Smith
    •  & Colin W. Taylor
  • Article
    | Open Access

    Extracellular vesicles (EVs) play a role in intercellular communication, however the precise biogenesis of different populations of EVs are not clear. Here, the authors follow the intracellular trafficking of two proteins before their secretion in EVs and report the biogenesis and protein markers of EV subtypes: ectosomes budding from the plasma membrane as well as exosomes from late endosomes.

    • Mathilde Mathieu
    • , Nathalie Névo
    •  & Clotilde Théry
  • Article
    | Open Access

    CD45 limits T cell activation, so its exclusion from the T cell immunological synapse is thought to occur as a means to enable TCR signalling. Here the authors use a variety of cellular imaging methods to show that CD45 is indeed excluded from the tips of the T cell microvilli and that this occurs prior to contact with antigen, indicating this exclusion is one of the initiating factors for antigen presentation and T cell activation.

    • Yunmin Jung
    • , Lai Wen
    •  & Klaus Ley
  • Article
    | Open Access

    Gangliosides such as GM1 present in the outer leaflet of the plasma membrane of eukaryotic cells are essential for many cellular functions and pathogenic interactions. Here the authors show that the acyl chain structure of GM1 determines the establishment of nanodomains when actively clustered by actin, which depended on membrane cholesterol and phosphatidylserine or superimposed by the GM1-binding bacterial cholera toxin.

    • Senthil Arumugam
    • , Stefanie Schmieder
    •  & Ludger Johannes
  • Article
    | Open Access

    Studying dynamic processes in mechanobiology has been challenging due to lack of appropriate tools. Here, the authors present an interference-based method, illuminated via two rapidly alternating wavelengths, which enables real-time mapping of nanoscale forces with sub-second mechanical fluctuations.

    • Andrew T. Meek
    • , Nils M. Kronenberg
    •  & Malte C. Gather
  • Article
    | Open Access

    Recent advances in super-resolution microscopy have made it possible to measure chromatin 3D structure and transcription in thousands of single cells. Here, authors present a deep learning-based approach to characterise how chromatin structure relates to transcriptional state of individual cells and determine which structural features of chromatin regulation are important for gene expression state.

    • Aparna R. Rajpurkar
    • , Leslie J. Mateo
    •  & Alistair N. Boettiger
  • Article
    | Open Access

    During transcription, RNA polymerase II (RNAP2) is recruited to promoters and phosphorylated stepwise; so far, these steps have not been visualized in a single-copy gene in live cells. Here the authors use single-molecule microscopy to visualize endogenous phosphorylated RNAP2 and nascent mRNA synthesis at a single locus in living cells.

    • Linda S. Forero-Quintero
    • , William Raymond
    •  & Timothy J. Stasevich
  • Article
    | Open Access

    Optical aberrations in Structured Illumination Microscopy (SIM) can lead to loss of resolution and artifacts making it unsuitable for thick samples. Here the authors combine Adaptive Optics and SIM (AO-3DSIM) to improve the 3D resolution and reduce artifacts, performing 3D-SIM in C.elegans.

    • Ruizhe Lin
    • , Edward T. Kipreos
    •  & Peter Kner
  • Article
    | Open Access

    In the genome, repetitive guanine-rich sequences have the potential to spontaneously fold into non-canonical DNA secondary structures known as G-quadruplex (G4). Using novel single-molecule imaging approaches, the authors reveal that G4 formation within active replication forks locally perturb replisome dynamics and damage response signaling, which require RPA and FANCJ for regulation.

    • Wei Ting C. Lee
    • , Yandong Yin
    •  & Eli Rothenberg
  • Article
    | Open Access

    Deep learning methods show great promise for the analysis of microscopy images but there is currently an accessibility barrier to many users. Here the authors report a convenient entry-level deep learning platform that can be used at no cost: ZeroCostDL4Mic.

    • Lucas von Chamier
    • , Romain F. Laine
    •  & Ricardo Henriques
  • Article
    | Open Access

    While recent studies suggest that transcriptional activators form condensates at active loci, less is known about the distribution of repressor proteins. Here, the authors develop an expression assay in living Ciona embryos and visualize puncta of Hes repressors, with the Groucho/TLE corepressor, observing that the Hes.a/Gro puncta have the properties of viscous liquid droplets that undergo limited fusion events due to association with DNA.

    • Nicholas Treen
    • , Shunsuke F. Shimobayashi
    •  & Michael Levine
  • Article
    | Open Access

    Phytoplankton account for a large proportion of global primary production and comprise a number of phylogenetically distinct lineages. Here, Uwizeye et al. use FIB-SEM to study ultrastructural plasticity of 7 distinct taxa and describe how subcellular organisation is linked to energy metabolism.

    • Clarisse Uwizeye
    • , Johan Decelle
    •  & Giovanni Finazzi
  • Article
    | Open Access

    How PRC1 recognises and interacts with its target genes remains poorly understood. Here, the authors use genome engineering and single particle tracking to dissect how PRC1 binds to chromatin in live mouse embryonic stem cells, revealing that this repressor is highly dynamic, with only a small fraction stably interacting with chromatin.

    • Miles K. Huseyin
    •  & Robert J. Klose
  • Article
    | Open Access

    Mitochondrial oxidation-induced cell death is an important physiological process activated by cancer therapeutics, but its investigation is challenging. Here, the authors report a multifunctional iridium(III) photosensitiser, Ir-OA, able to induce mitochondrial oxidative stress and monitor the corresponding changes in mitochondrial properties.

    • Chaiheon Lee
    • , Jung Seung Nam
    •  & Tae-Hyuk Kwon
  • Article
    | Open Access

    Open standard microscopy is urgently needed to give low-cost solutions to researchers and to overcome the reproducibility crisis in science. Here the authors present a 3D-printed, open-source modular microscopy toolbox UC2 (You. See. Too.) for a few hundred Euros.

    • Benedict Diederich
    • , René Lachmann
    •  & Rainer Heintzmann
  • Article
    | Open Access

    53BP1 is a crucial factor involved in double strand break repair which blocks DNA end resection affecting DNA repair pathway choice. Here the authors reveal by live cell nuclear architecture analysis the spatiotemporal dynamics of 53BP1 oligomerization during a DSB DNA damage response.

    • Jieqiong Lou
    • , David G. Priest
    •  & Elizabeth Hinde
  • Article
    | Open Access

    Determining the orientation of single molecules in super resolution imaging is challenging. Here, by adding polarization control to phase control in the Fourier plane of the imaging path, parameters such as 3D spatial position, 3D orientation and wobbling or dithering angle can be determined from single molecules.

    • Valentina Curcio
    • , Luis A. Alemán-Castañeda
    •  & Miguel A. Alonso
  • Article
    | Open Access

    Single-cell metabolomics can offer deep insights into the metabolic reprogramming that accompanies disease states. Here, the authors use Raman spectro-microscopy for non-invasive metabolite analysis and identification of druggable metabolic susceptibilities in single live melanoma cells.

    • Jiajun Du
    • , Yapeng Su
    •  & Lu Wei
  • Article
    | Open Access

    In vivo, cells migrate across a diverse landscape of extracellular matrix containing gaps which present a challenge for cells to protrude across. Here, the authors show that T-Plastin strengthens protrusive actin networks to promote protrusion, extracellular matrix gap-bridging, and cell migration.

    • Damien Garbett
    • , Anjali Bisaria
    •  & Tobias Meyer
  • Article
    | Open Access

    High density environmentally sensitive (HIDE) probes allow for long time-lapse super-resolution imaging of live cells. Here the authors develop a second HIDE probe with a bio-orthogonal labelling strategy to enable two-color nanoscopy of two organelles over extended periods.

    • Ling Chu
    • , Jonathan Tyson
    •  & Derek K. Toomre
  • Article
    | Open Access

    p53 mutants can promote tumorigenesis by affecting fundamental cellular pathways and functions. In this study, the authors demonstrate a novel mutant-p53/HIF1α/miR-30d axis that impacts Golgi structure, trafficking, and secretion of proteins essential for tumor growth and metastasis.

    • Valeria Capaci
    • , Lorenzo Bascetta
    •  & Giannino Del Sal
  • Article
    | Open Access

    Imaging specific proteins in the ultrastructural context largely relies on correlative light/electron microscopy, but fluorophore incompatibility and registration issues limit its use. Here the authors develop an expansion microscopy method with pan-labeling of the proteome to obtain EM-equivalent light microscopy images.

    • Ons M’Saad
    •  & Joerg Bewersdorf
  • Article
    | Open Access

    The regulation of microtubule (MT) dynamics in cancer cells within the tumor microenvironment is less understood. Here, the authors develop an imaging platform to examine MT dynamics in live xenograft models and show that pro-tumor macrophages modulate MT coherence and alignment to promote cancer cell migration.

    • Gaurav Luthria
    • , Ran Li
    •  & Miles A. Miller
  • Article
    | Open Access

    The three-dimensional architecture of the genome affects genomic functions. Here, the authors developed Multiplexed Imaging of Nucleome Architectures to measure multiscale chromatin folding, RNA profiles, and associations of numerous genomic regions with nuclear lamina and nucleoli in the same, single cells in heterogeneous tissue.

    • Miao Liu
    • , Yanfang Lu
    •  & Siyuan Wang
  • Article
    | Open Access

    Therapeutic siRNA becomes trapped in endosomes, limiting its efficacy. Here the authors use fluorescently-tagged galectin-9 as a biosensor for membrane damage to monitor endosomal escape of cholesterol-conjugated siRNA following treatment of small molecule membrane-destabilising drugs.

    • Hampus Du Rietz
    • , Hampus Hedlund
    •  & Anders Wittrup
  • Article
    | Open Access

    Aldosterone-producing zona glomerulosa cells in the adrenal gland arrange into rosette structures known to be important for morphogenesis. Here the authors show that the cells in the rosettes produce coordinated calcium activity bursts in response to angiotensin II that correlate with aldosterone production level.

    • Nick A. Guagliardo
    • , Peter M. Klein
    •  & Mark P. Beenhakker
  • Article
    | Open Access

    Selective ERK5 inhibitors target ERK5 kinase activity, but they do not phenocopy the effects of ERK5 genetic depletion. Here, the authors demonstrate that the direct interaction of these inhibitors to ERK5 kinase domain induces conformational changes that promote ERK5 nuclear translocation and transcriptional activities.

    • Pamela A. Lochhead
    • , Julie A. Tucker
    •  & Simon J. Cook
  • Article
    | Open Access

    Although loss of BRCA1 leads to defects in DNA double-strand break repair by homologous recombination (HR) and renders cells hypersensitive to PARP inhibitors, resistance to the drugs can arise. Here the authors reveal that PALB2 chromatin recruitment restores HR in BRCA1-deficient cells depleted of 53BP1.

    • Rimma Belotserkovskaya
    • , Elisenda Raga Gil
    •  & Stephen P. Jackson
  • Article
    | Open Access

    Lipid droplets are organelles that regulate lipid metabolism but if organellar contacts play a role during lipolysis is unclear. Here, the authors show that peroxisomes and peroxisomal protein PEX5 play pivotal roles in the spatial and temporal regulation of fasting-induced lipolysis by translocating ATGL onto lipid droplets

    • Jinuk Kong
    • , Yul Ji
    •  & Jae Bum Kim
  • Article
    | Open Access

    Glucagon-like peptide-1 receptor is an important regulator of appetite and glucose homeostasis. Here the authors describe super-resolution microscopy and in vivo imaging compatible fluorescent probes, which reveal endogenous glucagon-like peptide-1 receptor distribution and dynamics in islets and brain.

    • Julia Ast
    • , Anastasia Arvaniti
    •  & David J. Hodson
  • Article
    | Open Access

    Monomeric near-infrared (NIR) fluorescent proteins (FPs) from bacterial phytochromes bring potential advantages, but their brightness in cells is lower than dimeric NIR FPs. Here the authors develop enhanced monomeric NIR FPs enabling imaging across different scales without the trade-off between brightness and monomeric state.

    • Mikhail E. Matlashov
    • , Daria M. Shcherbakova
    •  & Vladislav V. Verkhusha
  • Article
    | Open Access

    Traction force microscopy is an effective method for measuring cellular forces but it is limited by planar geometry. Here the authors develop a facile method to produce deformable hydrogel particles and a reference-free computational method to resolve surface traction forces from particle shape deformation.

    • Daan Vorselen
    • , Yifan Wang
    •  & Julie A. Theriot
  • Article
    | Open Access

    Here, using high spatiotemporal resolution light-sheet and fluorescence microscopy, the authors investigate the role of cytoskeletal components on the intracellular transport of Rab11A and influenza virus (IAV) vRNP), and show a preference for Rab11A movement along microtubules that is not essential for IAV vRNP transport.

    • Amar R. Bhagwat
    • , Valerie Le Sage
    •  & Seema S. Lakdawala
  • Article
    | Open Access

    The Bin/Amphiphysin/Rvs167 (BAR) domain superfamily, which includes FCH-BAR (F-BAR) domain proteins are membrane-sculpting proteins. Here the authors combine a range of techniques and show that the F-BAR domain of growth-arrest specific protein 7 (GAS7) forms two-dimensional sheets on flat membranes and that these oligomeric assemblies of GAS7 are required for the formation of phagocytic cups in macrophages.

    • Kyoko Hanawa-Suetsugu
    • , Yuzuru Itoh
    •  & Shiro Suetsugu
  • Article
    | Open Access

    Pluripotent stem cell colonies are encircled by large cornerstone focal adhesions (FAs). Here, using super-resolution imaging, the authors describe features in the nanoscale makeup of these stable FAs such as inverted vinculin, lateral talin segregation and distinct kank protein distributions.

    • Aki Stubb
    • , Camilo Guzmán
    •  & Johanna Ivaska
  • Article
    | Open Access

    Epitope tags are widely used in various applications, but often lack versatility. Here, the authors introduce a small, alpha helical tag, which is recognized by a high affinity nanobody and can be used in a range of different applications, from protein purification to super-resolution imaging and in vivo detection of proteins.

    • Hansjörg Götzke
    • , Markus Kilisch
    •  & Steffen Frey
  • Article
    | Open Access

    Mitochondrial cristae organization and ER-mitochondria contact sites are critical structures for cellular function. Here, the authors use super-resolution microscopy to show that Miro GTPases form clusters required for normal ER-mitochondria contact sites formation and to link cristae organization to the mitochondrial transport machinery.

    • Souvik Modi
    • , Guillermo López-Doménech
    •  & Josef T. Kittler
  • Article
    | Open Access

    Internalized receptors are recycled back to the cell surface, but their precise mechanisms are unclear. Here, the authors show that the flotillin membrane proteins may regulate the transfer of internalized T cell receptors into Rab5 and Rab11-positive endosomes to support its rapid recycling.

    • Gregory M. I. Redpath
    • , Manuela Ecker
    •  & Jérémie Rossy
  • Article
    | Open Access

    Replication of Toxoplasma gondii requires replication and distribution of essential organelles such as micronemes. Here, Periz et al. show that micronemes are recycled from the mother to the forming daughter cells using a highly dynamic F-actin network that supports multidirectional vesicle transport.

    • Javier Periz
    • , Mario Del Rosario
    •  & Markus Meissner
  • Article
    | Open Access

    Pancreatic islets are composed of alpha-, beta-, as well as delta-cells and appropriate regulation of glucose homeostasis relies on auto- and paracrine cellular communication. Here, the authors study the role of delta-cell filopodia in this context by employing optogenetic and calcium imaging approaches.

    • Rafael Arrojo e Drigo
    • , Stefan Jacob
    •  & Per-Olof Berggren