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Circadian clock drives novel functions through transcriptional cascade

ABSTRACT: Using larval zebrafish as a model system, we applied a genome-wide transcriptome approach that allowed us to investigate circadian gene expression that can be associated with various tissues and cell types. Our analysis of circadian gene regulatory network revealed a general principle: circadian clock controls diverse aspects of circadian physiology through transcriptional cascade of transcription factors (TFs). As a proof of this principle, we focused on microphthalmia-associated transcription factor a (mitfa), a dark-induced TF controlling melanogenesis in melanocytes. We demonstrated experimentally that there is a circadian rhythm of melanin synthesis mediated by mitfa. The circadian rhythm of mitfa is in turn driven by both endogenous clock and external light/dark cycle. The circadian rhythm of melanin synthesis may play an important role in zebrafish’s adaptation to daily cycle of lighting condition in the environment.

ORGANISM(S): Danio rerio

PROVIDER: GSE37332 | GEO | 2012/04/26

SECONDARY ACCESSION(S): PRJNA162305

REPOSITORIES: GEO

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Circadian clock drives novel functions through transcriptional cascade

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