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Biology subjects

Takayama, M.

Publications and source records attributed to Takayama, M..

2 recordsLinked to original sources

Neural basis for anxiety and anxiety-related physiological responses during simulated driving: An fMRI study

While the exteroceptive and interoceptive prediction of a negative event increases a persons anxiety in daily life situations, the relationship between the brain mechanism of anxiety and the anxiety-related autonomic response has not been fully understood. In this fMRI study, we examined the neural basis of anxiety and anxiety-related autonomic responses in a daily driving situation. Participants viewed a driving video clip in the first-person perspective. During the video clip, participants were presented with a cue to indicate whether a subsequent crash could occur (attention condition) or not (safe condition). Enhanced activities in the anterior insula, bed nucleus of the stria terminalis, thalamus, and periaqueductal gray, and higher sympathetic nerve responses (pupil dilation and peripheral arterial stiffness) were triggered by the attention condition but not with the safe condition. Autonomic response-related functional connectivity was detected in the visual cortex, cerebellum, brainstem, and MCC/PCC with the right anterior insula and its adjacent regions as seed regions. Thus, the right anterior insula and adjacent regions, in collaboration with other regions play a role in eliciting anxiety based on the prediction of negative events, by mediating anxiety-related autonomic responses according to interoceptive information.

neuroscience↗

Optogenetic control of apical constriction induces synthetic morphogenesis in mammalian tissues

During embryonic development, cellular forces synchronize in space and time to generate functional tissue shapes. Apical constriction is one of these force-generating processes, and it is necessary to modulate epithelial curvature in fundamental morphogenetic events, such as neural tube folding. The emerging field of synthetic developmental biology proposes bottom-up approaches to examine the contribution of each cellular process to complex morphogenesis. However, the shortage of tools to manipulate three-dimensional (3D) shapes of mammalian tissues currently hinders the progress of the field. Here we report the development of "OptoShroom3", a new optogenetic tool that achieves fast spatiotemporal control of apical constriction in mammalian epithelia. Activation of OptoShroom3 through illumination of individual cells in an epithelial cell sheet reduced their apical surface while illumination of groups of cells caused deformation in the adjacent regions. By using OptoShroom3, we further manipulated 3D tissue shapes. Light-induced apical constriction provoked the folding of epithelial cell colonies on soft gels. Its application to murine and human neural organoids led to thickening of neuroepithelia, apical lumen reduction in optic vesicles, and flattening in neuroectodermal tissues. These results show that spatiotemporal control of apical constriction can trigger several types of 3D deformation depending on the initial tissue context.

developmental biology↗