Dataset Information

Acetylation of WCC is dispensable for the core circadian clock but differentially regulates acute light responses in Neurospora.

ABSTRACT: In the Neurospora circadian system, the White Collar Complex (WCC) formed by WC-1 and WC-2 drives expression of the frequency (frq) gene whose product FRQ feedbacks to inhibit transcriptional activity of WCC. Phosphorylation of WCC has been extensively studied, but the extent and significance of other post-translational modifications (PTM) have been poorly studied. To this end, we used mass-spectrometry to study alkylation sites on WCC, resulting in discovery of nine acetylation sites. Mutagenesis analysis showed most of the acetylation events individually do not play important roles in period determination. Moreover, mutating all the lysines falling in either half of WC-1 or all the lysine residues in WC-2 to arginines did not abolish circadian rhythms. In addition, we also found nine mono-methylation sites on WC-1, but like acetylation, individual ablation of most of the mono-methylation events did not result in a significant period change. Taken together, the data here suggest that acetylation or mono-methylation on WCC is not a determinant of the pace of the circadian feedback loop. The finding is consistent with a model in which repression of WCC's circadian activity is mainly controlled by phosphorylation. Interestingly, light-induced expression of some light-responsive genes has been modulated in certain wc-1 acetylation mutants, suggesting that WC-1 acetylation events differentially regulate light responses.

SUBMITTER: Wang B

PROVIDER: S-EPMC11325773 | biostudies-literature | 2024 Jun

REPOSITORIES: biostudies-literature

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Acetylation of WCC is dispensable for the core circadian clock but differentially regulates acute light responses in Neurospora.

Wang Bin B Adamo Mark E ME Zhou Xiaoying X Wang Ziyan Z Gerber Scott A SA Kettenbach Arminja N AN Dunlap Jay C JC

The Journal of biological chemistry 20240627 8

In the Neurospora circadian system, the White Collar Complex (WCC) formed by WC-1 and WC-2 drives expression of the frequency (frq) gene whose product FRQ feedbacks to inhibit transcriptional activity of WCC. Phosphorylation of WCC has been extensively studied, but the extent and significance of other post-translational modifications (PTM) have been poorly studied. To this end, we used mass-spectrometry to study alkylation sites on WCC, resulting in discovery of nine acetylation sites. Mutagenes ...[more]

PMID: 38944116

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Dataset Information

Acetylation of WCC is dispensable for the core circadian clock but differentially regulates acute light responses in Neurospora.

Publications

Acetylation of WCC is dispensable for the core circadian clock but differentially regulates acute light responses in Neurospora.

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