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NPAS4 regulates the transcriptional response of suprachiasmatic nucleus neurons to photic input

ABSTRACT: In mammals, the hypothalamic suprachiasmatic nucleus (SCN) is the master circadian pacemaker. It is primarily entrained by environmental photic stimuli. However, the molecular bases of the response of heterogeneous cells in the SCN to photic stimuli is not fully understood. In this study, we combined bulk RNA/ChIP/single nuclei sequencing with circadian behavioral assays to investigate cellular identities in the SCN and explore how they react to photic stimuli. We identified 3 major peptidergic cells in the SCN, Avp-expressing, Vip-expressing and Cck-expressing cells. In each peptidergic cell type, there is a light responsive cell cluster, and each of these is enriched for Neuronal PAS Domain Protein 4 (NPAS4) target genes. In addition, Npas4 null mice have a 1hr longer circadian period in constant darkness and a damped phase responsive curve to photic stimuli. Bulk RNA seq in Npas4-/- SCN revealed a reduced magnitude of light induced gene expression. Together, our data indicate that NPAS4 is part of the machinery that orchestrates the molecular response to photic stimuli in the SCN.

ORGANISM(S): Mus musculus

PROVIDER: GSE148252 | GEO | 2021/08/23

REPOSITORIES: GEO

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