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Transcriptional regulation of the Neurospora circadian clock gene wc-1 affects the phase of circadian output.

ABSTRACT: WHITE COLLAR-1 (WC-1) is the limiting component of the White Collar Complex (WCC) controlling expression of the Neurospora circadian clock protein Frequency (FRQ). Accumulation of WC-1 is supported by FRQ on a post-transcriptional level. Here, we show that transcription of wc-1 is organized in a complex way. Three promoters drive transcription of wc-1. Pdist is dependent on WCC. Pprox is independent of WCC in darkness, but inducible by light in a WCC-dependent manner. A third promoter, Pint, is located in the wc-1 open reading frame and promotes expression of an amino-terminally truncated WC-1 isoform of unknown function. Expression of wc-1 by Pdist or Pprox alone, or by a heterologous promoter, affects the entrained phase of circadian conidiation and the response of Neurospora to light. Our results indicate that transcriptional regulation of wc-1 is required to modulate the circadian phase of clock output.

SUBMITTER: Kaldi K

PROVIDER: S-EPMC1369249 | biostudies-literature | 2006 Feb

REPOSITORIES: biostudies-literature

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Transcriptional regulation of the Neurospora circadian clock gene wc-1 affects the phase of circadian output.

Káldi Krisztina K González Beatriz Herreros BH Brunner Michael M

EMBO reports 20060201 2

WHITE COLLAR-1 (WC-1) is the limiting component of the White Collar Complex (WCC) controlling expression of the Neurospora circadian clock protein Frequency (FRQ). Accumulation of WC-1 is supported by FRQ on a post-transcriptional level. Here, we show that transcription of wc-1 is organized in a complex way. Three promoters drive transcription of wc-1. Pdist is dependent on WCC. Pprox is independent of WCC in darkness, but inducible by light in a WCC-dependent manner. A third promoter, Pint, is ...[more]

PMID: 16374510

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