Publications by authors named "T Terai"

Genetically encoded calcium (Ca ) indicators (GECIs) are widely used for imaging neuronal activity, yet current limitations of existing red fluorescent GECIs have constrained their applicability. The inherently dim fluorescence and low signal-to-noise ratio of red-shifted GECIs have posed significant challenges. More critically, several red-fluorescent GECIs exhibit photoswitching when exposed to blue light, thereby limiting their applicability in all- optical experimental approaches.

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A chemigenetic indicator with an affinity suitable for imaging of intracellular sodium ions (Na) in mammalian cells was developed. The indicator, based on a chimera of green fluorescent protein (GFP) and HaloTag labeled with a synthetic crown ether chelator, was produced by a combination of rational design and directed evolution. In mammalian cells the indicator exhibited an approximately 100% increase in excitation ratio when the cells were treated with 20 mM Na and an ionophore.

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Potassium ion (K) is the most abundant metal ion in cells and plays an indispensable role in practically all biological systems. Although there have been reports of both synthetic and genetically encoded fluorescent K indicators, there remains a need for an indicator that is genetically targetable, has high specificity for K versus Na, and has a high fluorescent response in the red to far-red wavelength range. Here, we introduce a series of chemigenetic K indicators, designated as the HaloKbp1 series, based on the bacterial K-binding protein (Kbp) inserted into HaloTag7 self-labeled with environmentally sensitive rhodamine derivatives.

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Cells utilize ubiquitin as a posttranslational protein modifier to convey various signals such as proteasomal degradation. The dysfunction of ubiquitylation or following proteasomal degradation can give rise to the accumulation and aggregation of improperly ubiquitylated proteins, which is known to be a general causation of many neurodegenerative diseases. Thus, the characterization of substrate peptide sequences of E3 ligases is crucial in biological and pharmaceutical sciences.

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Background: Map-like redness, pathological intestinal metaplasia, is observed in one-fourth to one-third of patients 1 year after Helicobacter pylori eradication therapy, mainly in the corpus, and is a newly identified endoscopic risk factor for gastric cancer development after eradication. However, it is unclear whether intestinal metaplasia is present before eradication at the site where the map-like redness appears. We aimed to identify endoscopic findings that predict the occurrence of map-like redness before H.

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