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Matsumoto, G.

Publications and source records attributed to Matsumoto, G..

2 recordsLinked to original sources

Induction of the aggresome and insoluble tau aggregation using an optogenetic tool

Tauopathy is a spectrum of diseases characterized by fibrillary tau aggregate formation in neurons and glial cells in the brain. Tau aggregation originates in the brainstem and entorhinal cortex and then spreads throughout the brain in Alzheimers disease (AD), which is the most prevalent type of tauopathy. Understanding the mechanism by which locally developed tau pathology propagates throughout the brain is crucial for comprehending AD pathogenesis. Therefore, a novel model of tau pathology that artificially induces tau aggregation in targeted cells at specific times is essential. This study describes a novel optogenetic module, OptoTau, which is a human tau with the P301L mutation fused with a photosensitive protein CRY2olig, inducing various forms of tau according to the temporal pattern of blue light illumination pattern. Continuous blue light illumination for 12 h to Neuro2a cells that stably express OptoTau (OptoTauKI cells) formed clusters along microtubules, many of which eventually accumulated in aggresomes. Conversely, methanol-resistant tau aggregation was formed when alternating light exposure and darkness in 30-min cycles for 8 sets per day were repeated over 8 days. Methanol-resistant tau was induced more rapidly by repeating 5-min illumination followed by 25-min darkness over 24 h. These results indicate that OptoTau induced various tau aggregation stages based on the temporal pattern of blue light exposure. Thus, this technique exhibits potential as a novel approach to developing specific tau aggregation in targeted cells at desired time points. SignificanceThis study developed an approach to manipulate tau aggregation in a blue light-dependent manner using cells that stably express OptoTau, which is an optogenetic tool based on the CRY2olig module. Tau accumulation in aggresomes or stable tau aggregation were selectively induced by blue light illumination conditions. These results are crucial as they provide a new technological basis for establishing a singular point of tau aggregation in specific targeted cells at a particular time.

biophysics↗

Chloroplast genome assemblies and comparative analyses of major Vaccinium berry crops

BackgroundVaccinium is an economically important genus of berry crops in the family Ericaceae. Given the numerous hybridizations and polyploidization events among Vaccinium species, the taxonomy of this genus has remained uncertain and the subject of long debate. Therefore, the availability of more genomic resources for Vaccinium can provide useful tools for phylogenetic resolution, species identification, authentication of berry food products, and a framework for genetic engineering. ResultsIn this study, we assembled five Vaccinium chloroplast sequences representing the following berry types: northern highbush blueberry (V. corymbosum), southern highbush blueberry (V. corymbosum hybrids), rabbiteye blueberry (V. virgatum), lowbush blueberry (V. angustifolium), and bilberry (V. myrtillus). Two complete plastid genomes were achieved using long-read PacBio sequencing, while three draft sequences were obtained using short-read Illumina sequencing. Comparative analyses also included other previously available Vaccinium chloroplast sequences, especially the commercially important species V. macrocarpon (cranberry). The Vaccinium chloroplast genomes exhibited a circular quadripartite structure, with an overall highly conserved synteny and sequence identity among them. Despite their high similarity, we identified some polymorphic regions in terms of expansion/contraction of inverted repeats, gene copy number variation, simple sequence repeats, and single nucleotide polymorphisms. Phylogenetic analysis revealed multiple origins of highbush blueberry plastomes, likely due to the hybridization events during northern and southern highbush blueberry domestication. ConclusionsOur results enrich the genomic data availability for new Vaccinium species by sequencing and assembling the chloroplast DNA of major economically important berry types. Additional whole plastome analyses including more samples and wild species will be useful to obtain a refined knowledge of the maternal breeding history of blueberries and increase phylogenetic resolution at low taxonomic levels.

plant biology↗