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Sakaguchi, H.

Publications and source records attributed to Sakaguchi, H..

4 recordsLinked to original sources

Atf3 controls transitioning in female mitochondrial cardiomyopathy as identified by single-cell transcriptomics

Oxidative phosphorylation defects results in mitochondrial diseases, with cardiac involvement markedly impacting prognosis. However, the mechanisms underlying the transition from compensation to dysfunction in response to metabolic deficiency remain unclear, impeding the development of effective treatments. Here, we employed single-nucleus RNA sequencing (snRNA-seq) on hearts from mitochondrial cardiomyopathy (MCM) mice with cardiac-specific Ndufs6 knockdown (FS6KD). Pseudotime trajectory analysis of cardiomyocytes from early stage of female FS6KD hearts revealed dynamic cellular state transitioning from compensation to severe compromise, coincided with transient upregulation of a critical transcription factor, activating transcription factor 3 (Atf3). Genetic ablation or adeno-associated virus-mediated Atf3 knockdown in FS6KD mice effectively delayed cardiomyopathy progression in a female-specific manner. Notably, human MCM snRNA-seq revealed a similar transition, including the dynamic expression of ATF3. In conclusion, our findings highlight a fate-determining role of Atf3 in female MCM progression, providing a promising therapeutic candidate for the currently intractable disease.

cell biology↗

Influence of colour vision on attention to, and impression of, complex aesthetic images

Humans exhibit colour vision variations due to genetic polymorphisms, with trichromacy being the most common, while some people are classified as dichromats. Whether genetic differences in colour vision affect the way of viewing complex images remains unknown. Here, we investigated how people with different colour vision focused their gaze on aesthetic paintings by eye-tracking while freely viewing digital rendering of paintings and assessed individual impressions through a decomposition analysis of adjective ratings for the images. Gaze concentrated areas among trichromats were more highly correlated than those among dichromats. However, compared to the brief dichromatic experience with the simulated images, there was little effect of innate colour vision differences. These results indicate that chromatic information is instructive as a cue for guiding attention, whereas the impression of each person is unaffected by colour-vision genetics and would be normalised to their own sensory experience through ones own colour space.

neuroscience↗

Identification of a Novel SARS-CoV-2 Delta-Omicron Recombinant Virus in the United States

Recombination between SARS-CoV-2 virus variants can result in different viral properties (e.g., infectiousness or pathogenicity). In this report, we describe viruses with recombinant genomes containing signature mutations from Delta and Omicron variants. These genomes are the first evidence for a Delta-Omicron hybrid Spike protein in the United States.

genomics↗

The oxytocin system regulates tearing

Tears are an exocrine physiological fluid secreted onto the ocular surface from the lacrimal apparatus in all mammals. Limited research has been conducted on the functional neuronal circuitry of tear production. In particular, the neuronal mechanisms of emotional tearing, which is a physiological reaction harmonized with enhanced emotional arousal and assumed to be unique to humans, remain unclear. We identified that the oxytocin neurons in the paraventricular hypothalamus is functionally projected to the oxytocin receptor-expressing neurons in the lacrimation center of the superior salivatory nucleus. Optogenetic activation or inhibition of these neurons and/or receptors can modulate the superior salivatory nucleus dependent tear secretion mediated through oxytocin. Moreover, we identified that maternal behavior, nociceptive behavior stimulation, and aversive memory retrieval are linked to tearing in mice, and that these emotional linked tearing are suppressed by optogenetic inhibition of the corresponding oxytocin system. Thus, tearing could be regulated through functional connections between central oxytocin systems in the paraventricular hypothalamus and the superior salivatory nucleus.

animal behavior and cognition↗