REVEILLE2 thermosensitive splicing: a molecular basis for the integration of nocturnal temperature information by the Arabidopsis circadian clock

• Published in: The New phytologist Vol. 241; no. 1; pp. 283 - 297
• Main Authors: James, Allan B., Sharples, Chantal, Laird, Janet, Armstrong, Emily May, Guo, Wenbin, Tzioutziou, Nikoleta, Zhang, Runxuan, Brown, John W. S., Nimmo, Hugh G., Jones, Matthew A.
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01-01-2024
• Subjects: Alternative splicing; Arabidopsis; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Biological clocks; Chilling; Chloroplasts; circadian; Circadian Clocks - genetics; Circadian rhythm; Circadian Rhythm - genetics; Circadian rhythms; Cooling; Environmental changes; Environmental factors; Gene expression; Gene Expression Regulation, Plant; Genetics; isoform switch; Nocturnal; Photosynthesis; Plants; signaling; Temperature; Transcription; Transcriptomics; circadian; chilling; signaling; alternative splicing; Arabidopsis; isoform switch; temperature
• ISSN: 0028-646X; 1469-8137
• DOI: 10.1111/nph.19339

Summary
Cold stress is one of the major environmental factors that limit growth and yield of plants. However, it is still not fully understood how plants account for daily temperature fluctuations, nor how these temperature changes are integrated with other regulatory systems such as the circadian clock.
We demonstrate that REVEILLE2 undergoes alternative splicing after chilling that increases accumulation of a transcript isoform encoding a MYB‐like transcription factor. We explore the biological function of REVEILLE2 in Arabidopsis thaliana using a combination of molecular genetics, transcriptomics, and physiology.
Disruption of REVEILLE2 alternative splicing alters regulatory gene expression, impairs circadian timing, and improves photosynthetic capacity. Changes in nuclear gene expression are particularly apparent in the initial hours following chilling, with chloroplast gene expression subsequently upregulated.
The response of REVEILLE2 to chilling extends our understanding of plants immediate response to cooling. We propose that the circadian component REVEILLE2 restricts plants responses to nocturnal reductions in temperature, thereby enabling appropriate responses to daily environmental changes.