StayGold is a bright fluorescent protein (FP) that is over one order of magnitude more photostable than any of the currently available FPs across the full range of illumination intensities used in widefield microscopy and structured illumination microscopy, the latter of which is a widefield illumination-based technique. To compare the photostability of StayGold under other illumination modes with that of three other green-emitting FPs, namely EGFP, mClover3, and mNeonGreen, we expressed all four FPs as fusions to histone 2B in HeLa cells. Unlike the case of widefield microscopy, the photobleaching behavior of these FPs in laser scanning confocal microscopy (LSCM) is complicated.
View Article and Find Full Text PDFAlthough StayGold is a bright and highly photostable fluorescent protein, its propensity for obligate dimer formation may hinder applications in molecular fusion and membrane targeting. To attain monovalent as well as bright and photostable labeling, we engineered tandem dimers of StayGold to promote dispersibility. On the basis of the crystal structure of this fluorescent protein, we disrupted the dimerization to generate a monomeric variant that offers improved photostability and brightness compared to StayGold.
View Article and Find Full Text PDFPreexposure to mild stress often improves cellular tolerance to subsequent severe stress. Severe ethanol stress (10% v/v) causes persistent and pronounced translation repression in Saccharomyces cerevisiae. However, it remains unclear whether preexposure to mild stress can mitigate translation repression in yeast cells under severe ethanol stress.
View Article and Find Full Text PDFTor complex 1 (TORC1), a master regulator of cell growth, is an evolutionarily conserved protein kinase within eukaryotic organisms. To control cell growth, TORC1 governs translational processes by phosphorylating its substrate proteins in response to cellular nutritional cues. Mammalian TORC1 (mTORC1) assumes the responsibility of phosphorylating the eukaryotic translation initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1) to regulate its interaction with eIF4E.
View Article and Find Full Text PDFSince yeast research under laboratory conditions is usually conducted at 25-30°C (moderate temperature range), most of the findings on yeast physiology are based on analyses in this temperature range. Due to inefficiencies in cultivation and analysis, insufficient information is available on yeast physiology in the low-temperature range, although alcoholic beverage production is often conducted at relatively low temperatures (around 15°C). Recently, we reported that severe ethanol stress (10% v/v) inhibits proteasomal proteolysis in yeast cells under laboratory conditions at 28°C.
View Article and Find Full Text PDFWe cloned and characterized two new coral fluorescent proteins: h2-3 and 1-41. h2-3 formed an obligate dimeric complex and exhibited bright green fluorescence. On the other hand, 1-41 formed a highly multimeric complex and exhibited dim red fluorescence.
View Article and Find Full Text PDFBiochim Biophys Acta Gen Subj
December 2022
Background: Although the budding yeast, Saccharomyces cerevisiae, produces ethanol via alcoholic fermentation, high-concentration ethanol is harmful to yeast cells. Severe ethanol stress (> 9% v/v) inhibits protein synthesis and increases the level of intracellular protein aggregates. However, its effect on proteolysis in yeast cells remains largely unknown.
View Article and Find Full Text PDFThe low photostability of fluorescent proteins is a limiting factor in many applications of fluorescence microscopy. Here we present StayGold, a green fluorescent protein (GFP) derived from the jellyfish Cytaeis uchidae. StayGold is over one order of magnitude more photostable than any currently available fluorescent protein and has a cellular brightness similar to mNeonGreen.
View Article and Find Full Text PDFAt the ICRP International Conference on Recovery After Nuclear Accidents Session 3.4 Forum on the Transmission of Experience held in December 2020, a panel discussion took place on the topic, 'How to overcome the difficulty to talk about the experience of nuclear accidents?'. The facilitator was Ryoko Ando (NPO Fukushima Dialogue) and the following six people participated as panelists: Atsushi Chiba (teacher at Fukushima Prefectural Asaka High School), Yoshiko Aoki (NPO Group of Storytellers About 311 in Tomioka), Miku Endo (Great East Japan Earthquake and Nuclear Disaster Memorial Museum), Kenji Shiga (former Director of Hiroshima Peace Memorial Museum), Thierry Schneider (Centre d'étude sur l'Evaluation de la Protection dans le domaine Nucléaire), and Noboru Takamura (Director of Great East Japan Earthquake and Nuclear Disaster Memorial Museum, Nagasaki University).
View Article and Find Full Text PDFAt the time of the accident at Fukushima Daiichi nuclear power plant in 2011, I was living in Iwaki City with my two children and my husband. With our home damaged by the tsunami and the deteriorating status following the situation at the nuclear power plant, we spent 2 years as evacuees before returning to Iwaki City. Subsequently, I decided to work as a radiation counsellor in the Suetsugi district of Iwaki City.
View Article and Find Full Text PDFDysfunctional mitochondria accumulate in many human diseases. Accordingly, mitophagy, which removes these mitochondria through lysosomal degradation, is attracting broad attention. Due to uncertainties in the operational principles of conventional mitophagy probes, however, the specificity and quantitativeness of their readouts are disputable.
View Article and Find Full Text PDFSuper-resolution optical fluctuation imaging (SOFI) offers a simple and affordable alternative to other super-resolution (SR) imaging techniques. The theoretical resolution enhancement of SOFI scales linearly with the order of cumulants, while the imaging conditions exhibit less photo-toxicity to the living samples as compared to other SR methods. High order SOFI could, therefore, be a method of choice for dynamic live cell imaging.
View Article and Find Full Text PDFSeven years have passed since the Tokyo Electric Power Company Fukushima Dai-ichi nuclear power plant disaster in March 2011. The actions taken by the Japanese government, such as issuing evacuation orders and setting decontamination and food safety standards, created huge confusion in society that led to a breakdown of trust. The residents of Suetsugi, a small village located about 30 km south of the plant, sought to understand and overcome the effects of radiation by measuring contamination and personal dose, etc.
View Article and Find Full Text PDFThe fluorescent protein toolbox has revolutionized experimental biology. Despite this advance, no fluorescent proteins have been identified from vertebrates, nor has chromogenic ligand-inducible activation or clinical utility been demonstrated. Here, we report the cloning and characterization of UnaG, a fluorescent protein from Japanese eel.
View Article and Find Full Text PDFAdvanced fluorescence imaging, including subdiffraction microscopy, relies on fluorophores with controllable emission properties. Chief among these fluorophores are the photoactivatable fluorescent proteins capable of reversible on/off photoswitching or irreversible green-to-red photoconversion. IrisFP was recently reported as the first fluorescent protein combining these two types of phototransformations.
View Article and Find Full Text PDFOptical methods for viewing neuronal populations and projections in the intact mammalian brain are needed, but light scattering prevents imaging deep into brain structures. We imaged fixed brain tissue using Scale, an aqueous reagent that renders biological samples optically transparent but completely preserves fluorescent signals in the clarified structures. In Scale-treated mouse brain, neurons labeled with genetically encoded fluorescent proteins were visualized at an unprecedented depth in millimeter-scale networks and at subcellular resolution.
View Article and Find Full Text PDFThe study of osteocytes has progressed in chicks. We examined whether chick osteocyte data can be applied to other species. We used mice for comparison because they are common clinical tools in biomedical research and useful for future study.
View Article and Find Full Text PDFIntroduction: The aims of this study were to assess the peer assessment rating (PAR) index in relation to perceived treatment needs for maxillary protrusion in Japanese subjects and to investigate how perceived orthodontic treatment needs change with increased experience in dentistry and orthodontics.
Methods: The subjects were 155 persons (73 men, 82 women; mean age, 24.2 years; SD, 4.
Photochem Photobiol Sci
February 2010
Photoswitchable fluorophores play an essential role in super-resolution fluorescence microscopy, including techniques such as photoactivated localization microscopy (PALM). A determining factor in the precision of the images generated by PALM measurements is the photon numbers that can be detected from the fluorophores. Dronpa is a reversibly photoswitchable fluorescent protein that has been successfully used in PALM experiments.
View Article and Find Full Text PDFAim: Although interferon (IFN)/ribavirin is the mainstream combination treatment for chronic hepatitis C in patients with a high viral load, ribavirin is problematic for women of childbearing age and patients with anemia. Therefore we needed to establish a new regimen without ribavirin.
Methods: We devised a new regimen (same-day beta/alpha2b) to administer IFN-beta and alpha2b on the same-day, and compared it with IFN-alpha2b alone and IFN-alpha2b plus ribavirin.
Osteocytes are surrounded by hard bone matrix, and it has not been possible previously to directly observe the in situ architecture of osteocyte morphology in bone. Electron microscope tomography, however, is a technique that has the unique potential to provide three-dimensional (3D) visualization of cellular ultrastructure. This approach is based on reconstruction of 3D volumes from a tilt series of electron micrographs of cells, and resolution at the nanometer level has been achieved.
View Article and Find Full Text PDFAm J Orthod Dentofacial Orthop
January 2009
Introduction: Our aims in this study were to determine the anteroposterior facial relationship that is regarded as most attractive by Japanese laypersons in a questionnaire survey and to evaluate which analysis of the soft-tissue profile is most suitable for Japanese people.
Methods: We showed 262 Japanese laypersons (121 male, 141 female) 9 morphed profile images with Point B and menton anteriorly or distally moved by software and asked them to number them sequentially according to their attractiveness. To examine which analysis best reflects facial attractiveness as judged by laypersons, we made 5 types of analyses of the facial profile with 11 variables in the 9 images.
The second-order nonlinear optical properties of green fluorescent proteins (GFPs), such as the photoswitchable Dronpa and enhanced GFP (EGFP), have been studied at both the theoretical and experimental levels. In the case of Dronpa, both approaches are consistent in showing the rather counterintuitive result of a larger second-order nonlinear polarizability (or first hyperpolarizability, beta) for the protonated state, which has a higher transition energy, than for the deprotonated, fluorescent state with its absorption at lower energy. Moreover, the value of beta for the protonated form of Dronpa is among the highest reported for proteins.
View Article and Find Full Text PDFThe structural basis for the photochromism in the fluorescent protein Dronpa is poorly understood, because the crystal structures of the bright state of the protein did not provide an answer to the mechanism of the photochromism, and structural determination of the dark state has been elusive. We performed NMR analyses of Dronpa in solution at ambient temperatures to find structural flexibility of the protein in the dark state. Light-induced changes in interactions between the chromophore and beta-barrel are responsible for switching between the two states.
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