Suprachiasmatic nucleus-wide estimation of oscillatory temporal dynamics

PLoS Computational Biology, Journal Year: 2025, Volume and Issue: 21(3), P. e1012855 - e1012855

Published: March 6, 2025

The suprachiasmatic nucleus (SCN), locus of a circadian clock, is small approximately 20,000 neurons that oscillate with period about 24 hours. While individual produce oscillations even when dispersed in culture, the coherence and robustness oscillation SCN as whole dependent on its circuitry. Surprisingly, intact do not all phase each other. To understand oscillatory dynamics across nucleus, we develop model relation to their PER2 expression at particular subjective time (CT1900) using series data from slice preparations. Next, use model, which produces surprisingly good fit data, estimate oscillator single point snapshot measurements intact, unsliced SCN-wide tissue. monitor temporal changes PER2::LUC imaging an ex vivo preparation. study fixed generated by staining tissue clearing protocol. Because expression, measured slices are directly comparable, estimated requires calibrating constant. results indicate our provides therefore meaningful method for estimating permitting virtual interventions such slicing. We next compare circuits those have been disrupted slicing Kuramoto simulate dynamics. support prior evidence damage done coronal has most disruptive impact oscillation, while horizontal least damage. importance connectivity along caudal-to-rostral axis circuit organization depends flow information. In summary, construction this major finding paper. Our modeling allows us perform previously impossible analysis static captured point.

Language: Английский

Connectomic Organization of the Suprachiasmatic Nucleus

Published: Oct. 22, 2024

Abstract The suprachiasmatic nucleus (SCN), the mammalian master clock, is a special structure dedicated to time computation. However, connectomic understanding of as whole lacking. Using serial section electron microscopy, we reconstructed multiscale and multimodal SCN communication networks. Intra-SCN synaptic network consists 9,566 morphologically similar neurons 4.3 million synapses, organized into circuitries that interact with SCN-traversing axon fascicles. Strikingly, engage in unique soma-soma ephaptic interaction, forming 2,038 electrotonic integrative units largest overlapping light-responsive area (LRA). SCN’s paracrine modality contains 47,396 μm 3 dense core vesicles, notable scarcity LRA, suggesting cross-modal coordination functional integration. These distinct features provide comprehensive insights system architecture circadian clock.

Language: Английский