Carole Gauron
PSL Research University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Carole Gauron.
Nature Chemical Biology | 2014
Arnaud Gautier; Carole Gauron; Michel Volovitch; David Bensimon; Ludovic Jullien; Sophie Vriz
The possibility offered by photocontrolling the activity of biomolecules in vivo while recording physiological parameters is opening up new opportunities for the study of physiological processes at the single-cell level in a living organism. For the last decade, such tools have been mainly used in neuroscience, and their application in freely moving animals has revolutionized this field. New photochemical approaches enable the control of various cellular processes by manipulating a wide range of protein functions in a noninvasive way and with unprecedented spatiotemporal resolution. We are at a pivotal moment where biologists can adapt these cutting-edge technologies to their system of study. This user-oriented review presents the state of the art and highlights technical issues to be resolved in the near future for wide and easy use of these powerful approaches.
Scientific Reports | 2013
Carole Gauron; Christine Rampon; Mohamed Bouzaffour; Eliane Ipendey; Jérémie Teillon; Michel Volovitch; Sophie Vriz
A major issue in regenerative medicine is the role of injury in promoting cell plasticity. Here we explore the function of reactive oxygen species (ROS) induced through lesions in adult zebrafish. We show that ROS production, following adult fin amputation, is tightly regulated in time and space for at least 24 hours, whereas ROS production remains transient (2 hours) in mere wound healing. In regenerative tissue, ROS signaling triggers two distinct parallel pathways: one pathway is responsible for apoptosis, and the other pathway is responsible for JNK activation. Both events are involved in the compensatory proliferation of stump epidermal cells and are necessary for the progression of regeneration. Both events impact the Wnt, SDF1 and IGF pathways, while apoptosis only impacts progenitor marker expression. These results implicate oxidative stress in regeneration and provide new insights into the differences between healing and regeneration.
ACS Chemical Biology | 2013
Ludovic Fournier; Carole Gauron; Lijun Xu; Isabelle Aujard; Thomas Le Saux; Nathalie Gagey-Eilstein; Sylvie Maurin; Sylvie Dubruille; Jean-Bernard Baudin; David Bensimon; Michel Volovitch; Sophie Vriz; Ludovic Jullien
The small and synthetically easily accessible 7-diethylamino-4-thiocoumarinylmethyl photolabile protecting group has been validated for uncaging with blue light. It exhibits a significant action cross-section for uncaging in the 470-500 nm wavelength range and a low light absorption between 350 and 400 nm. These attractive features have been implemented in living zebrafish embryos to perform chromatic orthogonal photoactivation of two biologically active species controlling biological development with UV and blue-cyan light sources, respectively.
ChemBioChem | 2010
Deepak Kumar Sinha; Pierre Neveu; Nathalie Gagey; Isabelle Aujard; Chouaha Benbrahim-Bouzidi; Thomas Le Saux; Christine Rampon; Carole Gauron; Bernard Goetz; Sylvie Dubruille; Marc Baaden; Michel Volovitch; David Bensimon; Sophie Vriz; Ludovic Jullien
We have implemented a noninvasive optical method for the fast control of protein activity in a live zebrafish embryo. It relies on releasing a protein fused to a modified estrogen receptor ligand binding domain from its complex with cytoplasmic chaperones, upon the local photoactivation of a nonendogenous caged inducer. Molecular dynamics simulations were used to design cyclofen‐OH, a photochemically stable inducer of the receptor specific for 4‐hydroxy‐tamoxifen (ERT2). Cyclofen‐OH was easily synthesized in two steps with good yields. At submicromolar concentrations, it activates proteins fused to the ERT2 receptor. This was shown in cultured cells and in zebrafish embryos through emission properties and subcellular localization of properly engineered fluorescent proteins. Cyclofen‐OH was successfully caged with various photolabile protecting groups. One particular caged compound was efficient in photoinducing the nuclear translocation of fluorescent proteins either globally (with 365 nm UV illumination) or locally (with a focused UV laser or with two‐photon illumination at 750 nm). The present method for photocontrol of protein activity could be used more generally to investigate important physiological processes (e.g., in embryogenesis, organ regeneration and carcinogenesis) with high spatiotemporal resolution.
Zebrafish | 2010
Deepak Kumar Sinha; Pierre Neveu; Nathalie Gagey; Isabelle Aujard; Thomas Le Saux; Christine Rampon; Carole Gauron; Koichi Kawakami; Christoph Leucht; Laure Bally-Cuif; Michel Volovitch; David Bensimon; Ludovic Jullien; Sophie Vriz
We implemented a noninvasive optical method for the fast control of Cre recombinase in single cells of a live zebrafish embryo. Optical uncaging of the caged precursor of a nonendogeneous steroid by one- or two-photon illumination was used to restore Cre activity of the CreER(T2) fusion protein in specific target cells. This method labels single cells irreversibly by inducing recombination in an appropriate reporter transgenic animal and thereby can achieve high spatiotemporal resolution in the control of gene expression. This technique could be used more generally to investigate important physiological processes (e.g., in embryogenesis, organ regeneration, or carcinogenesis) with high spatiotemporal resolution (single cell and 10-min scales).
Proceedings of the National Academy of Sciences of the United States of America | 2016
Marie-Aude Plamont; Emmanuelle Billon-Denis; Sylvie Maurin; Carole Gauron; Frederico M. Pimenta; Christian G. Specht; Jian Shi; Jérôme Quérard; Buyan Pan; Julien Rossignol; Karine Moncoq; Nelly Morellet; Michel Volovitch; Ewen Lescop; Yong Chen; Antoine Triller; Sophie Vriz; Thomas Le Saux; Ludovic Jullien; Arnaud Gautier
Significance We developed a small protein tag enabling fluorescent labeling of proteins in living cells and in multicellular organisms through the specific binding and activation of a cell-permeant and nontoxic fluorogenic ligand. This tag, called Yellow Fluorescence-Activating and absorption-Shifting Tag (Y-FAST), was engineered by directed evolution from the Photoactive Yellow Protein. Y-FAST distinguishes itself from other labeling methods because the fluorogen binding is highly dynamic and fully reversible. Apart from providing new opportunities in superresolution imaging and biosensor design, this feature enables rapid switching on and off of the fluorescence of a fusion protein by addition or withdrawing of the fluorogenic ligand, opening exciting ways to perform sequential multiplexing imaging. This paper presents Yellow Fluorescence-Activating and absorption-Shifting Tag (Y-FAST), a small monomeric protein tag, half as large as the green fluorescent protein, enabling fluorescent labeling of proteins in a reversible and specific manner through the reversible binding and activation of a cell-permeant and nontoxic fluorogenic ligand (a so-called fluorogen). A unique fluorogen activation mechanism based on two spectroscopic changes, increase of fluorescence quantum yield and absorption red shift, provides high labeling selectivity. Y-FAST was engineered from the 14-kDa photoactive yellow protein by directed evolution using yeast display and fluorescence-activated cell sorting. Y-FAST is as bright as common fluorescent proteins, exhibits good photostability, and allows the efficient labeling of proteins in various organelles and hosts. Upon fluorogen binding, fluorescence appears instantaneously, allowing monitoring of rapid processes in near real time. Y-FAST distinguishes itself from other tagging systems because the fluorogen binding is highly dynamic and fully reversible, which enables rapid labeling and unlabeling of proteins by addition and withdrawal of the fluorogen, opening new exciting prospects for the development of multiplexing imaging protocols based on sequential labeling.
Developmental Biology | 2016
Carole Gauron; Francesca Meda; Edmond Dupont; Shahad Albadri; Nicole Quenech’Du; Eliane Ipendey; Michel Volovitch; Filippo Del Bene; Alain Joliot; Christine Rampon; Sophie Vriz
It is now becoming evident that hydrogen peroxide (H2O2), which is constantly produced by nearly all cells, contributes to bona fide physiological processes. However, little is known regarding the distribution and functions of H2O2 during embryonic development. To address this question, we used a dedicated genetic sensor and revealed a highly dynamic spatio-temporal pattern of H2O2 levels during zebrafish morphogenesis. The highest H2O2 levels are observed during somitogenesis and organogenesis, and these levels gradually decrease in the mature tissues. Biochemical and pharmacological approaches revealed that H2O2 distribution is mainly controlled by its enzymatic degradation. Here we show that H2O2 is enriched in different regions of the developing brain and demonstrate that it participates to axonal guidance. Retinal ganglion cell axonal projections are impaired upon H2O2 depletion and this defect is rescued by H2O2 or ectopic activation of the Hedgehog pathway. We further show that ex vivo, H2O2 directly modifies Hedgehog secretion. We propose that physiological levels of H2O2 regulate RGCs axonal growth through the modulation of Hedgehog pathway.
Antioxidants & Redox Signaling | 2016
Francesca Meda; Carole Gauron; Christine Rampon; Jérémie Teillon; Michel Volovitch; Sophie Vriz
Abstract Aims: Recent advances in redox biology have emphasized the role of hydrogen peroxide (H2O2) in the modulation of signaling pathways and revealed that H2O2 plays a role in cellular remodeling in adults. Thus, an understanding of the mechanisms that control H2O2 levels in mature tissue would be of great interest. Results: We used a denervation strategy to demonstrate that sensory neurons are responsible for controlling H2O2 levels under normal conditions and after being lesioned. Moreover, we demonstrate that severed nerves respond to appendage amputation via the induction of Hedgehog signaling and that this signaling is responsible for H2O2 production in the wounded epidermis. Finally, we show that H2O2 and nerve growth are regulated via reciprocal action in adults. Innovation and Conclusion: These data support a new paradigm for the regulation of tissue homeostasis: H2O2 attracts nerves and nerves control H2O2 levels in a positive feedback loop. This finding suggests that the peripheral nerve redox environment could be a target for manipulating cell plasticity in adults. Antioxid. Redox Signal. 24, 299–311.
Angewandte Chemie | 2015
Jérôme Quérard; Tal‐Zvi Markus; Marie-Aude Plamont; Carole Gauron; Pengcheng Wang; Agathe Espagne; Michel Volovitch; Sophie Vriz; Vincent Croquette; Arnaud Gautier; Thomas Le Saux; Ludovic Jullien
Non-invasive separation-free protocols are attractive for analyzing complex mixtures. To increase selectivity, an analysis under kinetic control, through exploitation of the photochemical reactivity of labeling contrast agents, is described. The simple protocol is applied in optical fluorescence microscopy, where autofluorescence, light scattering, as well as spectral crowding presents limitations. Introduced herein is OPIOM (out-of-phase imaging after optical modulation), which exploits the rich kinetic signature of a photoswitching fluorescent probe to increase selectively and quantitatively its contrast. Filtering the specific contribution of the probe only requires phase-sensitive detection upon matching the photoswitching dynamics of the probe and the intensity and frequency of a modulated monochromatic light excitation. After in vitro validation, we applied OPIOM for selective imaging in mammalian cells and zebrafish, thus opening attractive perspectives for multiplexed observations in biological samples.
Development | 2012
Lijun Xu; Zhiping Feng; Deepak Kumar Sinha; Bertrand Ducos; Yuval Ebenstein; Arbel D. Tadmor; Carole Gauron; Thomas Le Saux; Shuo Lin; Shimon Weiss; Sophie Vriz; Ludovic Jullien; David Bensimon
All-trans retinoic acid (RA) is a key player in many developmental pathways. Most methods used to study its effects in development involve continuous all-trans RA activation by incubation in a solution of all-trans RA or by implanting all-trans RA-soaked beads at desired locations in the embryo. Here we show that the UV-driven photo-isomerization of 13-cis RA to the trans-isomer (and vice versa) can be used to non-invasively and quantitatively control the concentration of all-trans RA in a developing embryo in time and space. This facilitates the global or local perturbation of developmental pathways with a pulse of all-trans RA of known concentration or its inactivation by UV illumination. In zebrafish embryos in which endogenous synthesis of all-trans RA is impaired, incubation for as little as 5 minutes in 1 nM all-trans RA (a pulse) or 5 nM 13-cis RA followed by 1-minute UV illumination is sufficient to rescue the development of the hindbrain if performed no later than bud stage. However, if subsequent to this all-trans RA pulse the embryo is illuminated (no later than bud stage) for 1 minute with UV light (to isomerize, i.e. deactivate, all-trans RA), the rescue of hindbrain development is impaired. This suggests that all-trans RA is sequestered in embryos that have been transiently exposed to it. Using 13-cis RA isomerization with UV light, we further show that local illumination at bud stage of the head region (but not the tail) is sufficient to rescue hindbrain formation in embryos whose all-trans RA synthetic pathway has been impaired.