StayGold photostability under different illumination modes.

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.

StayGold variants for molecular fusion and membrane-targeting applications.

Although 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.

A highly photostable and bright green fluorescent protein.

The 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.

Autopsy findings of a patient with severe COVID-19 treated with long-term extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation (ECMO) therapy in patients with coronavirus disease 2019 (COVID-19) has a low frequency of use, and thus pathological findings in such patients are valuable. In this case report, a 62-year-old man with a history of hypertension presented with a runny nose. After an at-home COVID-19 positive test, he developed dyspnea and fever.

Visualizing and Modulating Mitophagy for Therapeutic Studies of Neurodegeneration.

Dysfunctional 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.

Single-cell bioluminescence imaging of deep tissue in freely moving animals.

Bioluminescence is a natural light source based on luciferase catalysis of its substrate luciferin. We performed directed evolution on firefly luciferase using a red-shifted and highly deliverable luciferin analog to establish AkaBLI, an all-engineered bioluminescence in vivo imaging system. AkaBLI produced emissions in vivo that were brighter by a factor of 100 to 1000 than conventional systems, allowing noninvasive visualization of single cells deep inside freely moving animals.

Live imaging-based model selection reveals periodic regulation of the stochastic G1/S phase transition in vertebrate axial development.

In multicellular organism development, a stochastic cellular response is observed, even when a population of cells is exposed to the same environmental conditions. Retrieving the spatiotemporal regulatory mode hidden in the heterogeneous cellular behavior is a challenging task. The G1/S transition observed in cell cycle progression is a highly stochastic process.

Genomic and non-genomic effects of glucocorticoids on allergic rhinitis model in mice.

Glucocorticoids (GCs) are well known for their anti-inflammatory effects, which are elicited through a transcriptional mechanism via a cytosolic glucocorticoid receptor (cGR)-mediated genomic effect. However, recent in vitro studies report that GCs can act as a membrane glucocorticoid receptor (mGR). This study aimed to examine whether mometasone furoate (MF) influences the nasal symptoms induced by histamine, substance P, ATP.

Software for precise tracking of cell proliferation.

We have developed a multi-target cell tracking program TADOR, which we applied to a series of fluorescence images. TADOR is based on an active contour model that is modified in order to be free of the problem of locally optimal solutions, and thus is resistant to signal fluctuation and morphological changes. Due to adoption of backward tracing and addition of user-interactive correction functions, TADOR is used in an off-line and semi-automated mode, but enables precise tracking of cell division.

A fluorescence spotlight on the clockwork development and metabolism of bone.

Biological phenomena that exhibit periodic activity are often referred as biorhythms or biological clocks. Among these, circadian rhythms, cyclic patterns reflecting a 24-h cycle, are the most obvious in many physiological activities including bone growth and metabolism. In the late 1990s, several clock genes were isolated and their primary structures and functions were identified.

Effect of 5-aminosalicylate on allergic rhinitis model in mice.

Previous studies have shown that peroxisome proliferator-activated receptor gamma (PPARgamma) is involved in allergic rhinitis. It has been reported that 5-aminosalicylate (5-ASA) has an affinity for PPARgamma, but the effects of 5-ASA on the nasal symptoms of allergic rhinitis are unclear. This study aimed to clarify the effects of 5-ASA on nasal symptoms in an allergic rhinitis model in mice.

Illuminating cell-cycle progression in the developing zebrafish embryo.

By exploiting the cell-cycle-dependent proteolysis of two ubiquitination oscillators, human Cdt1 and geminin, which are the direct substrates of SCF(Skp2) and APC(Cdh1) complexes, respectively, Fucci technique labels mammalian cell nuclei in G(1) and S/G(2)/M phases with different colors. Transgenic mice expressing these G(1) and S/G(2)/M markers offer a powerful means to investigate the coordination of the cell cycle with morphogenetic processes. We attempted to introduce these markers into zebrafish embryos to take advantage of their favorable optical properties.

Possible mechanism of polycation liposome (PCL)-mediated gene transfer.

A novel gene transfer system utilizing polycation liposomes (PCLs), obtained by modifying liposomes with cetyl polyethylenimine (PEI), was previously developed (Gene Ther. 7 (2002) 1148). PCLs show notable transfection efficiency with low cytotoxicity.

Polycation liposome-mediated gene transfer in vivo.

The polycation liposome (PCL), a recently developed gene transfer system, is simply prepared by a modification of liposomes with cetylated polyethylenimine (PEI), and shows remarkable transgene efficiency with low cytotoxicity. In the present study, we investigated the applicability of PCLs for in vivo gene transfer, since the PCL-mediated transgene efficiency was found to be maintained in the presence of serum. PCLs composed of dioleoylphosphatidylethanolamine (DOPE) with 5 mol% cetyl PEI (PEI average mr.