journal article

Journal Article

Proceedings of the National Academy of Sciences of the United States of America. 2018, 115(23), p. 5980-5985

Two Ck1δ transcripts regulated by m6A methylation code for two antagonistic kinases in the control of the circadian clock

National Academy of Sciences

English

2018-06-05

https://doi.org/10.1073/pnas.1721371115

Fustin, J.-M., Kojima, R., Itoh, K., Chang, H.-Y., Shiqi, Y., Zhuang, B., . . . Okamura, H. (2018). Two Ck1δ transcripts regulated by m6A methylation code for two antagonistic kinases in the control of the circadian clock. Proceedings of the National Academy of Sciences of the United States of America, 115(23), 5980-5985. doi:10.1073/pnas.1721371115

The N6-methylation of internal adenosines (m6A) in mRNA has been quantified and localized throughout the transcriptome. However, the physiological significance of m6A in most highly methylated mRNAs is unknown. It was demonstrated previously that the circadian clock, based on transcription-translation negative feedback loops, is sensitive to the general inhibition of m6A. Here, we show that the Casein Kinase 1 Delta mRNA (Ck1δ), coding for a critical kinase in the control of circadian rhythms, cellular growth, and survival, is negatively regulated by m6A. Inhibition of Ck1δ mRNA methylation leads to increased translation of two alternatively spliced CK1δ isoforms, CK1δ1 and CK1δ2, uncharacterized until now. The expression ratio between these isoforms is tissue-specific, CK1δ1 and CK1δ2 have different kinase activities, and they cooperate in the phosphorylation of the circadian clock protein PER2. While CK1δ1 accelerates the circadian clock by promoting the decay of PER2 proteins, CK1δ2 slows it down by stabilizing PER2 via increased phosphorylation at a key residue on PER2 protein. These observations challenge the previously established model of PER2 phosphorylation and, given the multiple functions and targets of CK1δ, the existence of two isoforms calls for a re-evaluation of past research when CK1δ1 and CK1δ2 were simply CK1δ.

© 2018 the Author(s). Published by PNAS. This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

78572

Two Ck1δ transcripts regulated by m6A methylation code for two antagonistic kinases in the control of the circadian clock

National Academy of Sciences

English

2018-06-05

Proceedings of the National Academy of Sciences of the United States of America

115

23

5980

5985

https://doi.org/10.1073/pnas.1721371115

00278424

https://hdl.handle.net/11094/78572