The cyclin‐dependent kinase G group defines a thermo‐sensitive alternative splicing circuit modulating the expression of Arabidopsis ATU2AF65A. (10th May 2018)

• Record Type: Journal Article
• Authors: Cavallari, Nicola; Nibau, Candida; Fuchs, Armin; Dadarou, Despoina; Barta, Andrea; Doonan, John H.
• Is Part Of: Plant journal. Volume 94:Number 6(2018)
• Page Start: 1010
• Page End: 1022
• Publication Date: 2018-05-10
• Subjects: alternative splicing -- thermo‐sensitivity -- cyclin‐dependent kinases -- Arabidopsis; Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.13914
• Languages: English
• ISSNs: 0960-7412

Abstract

Summary: The ability to adapt growth and development to temperature variations is crucial to generate plant varieties resilient to predicted temperature changes. However, the mechanisms underlying plant response to progressive increases in temperature have just started to be elucidated. Here, we report that the cyclin‐dependent kinase G1 (CDKG1) is a central element in a thermo‐sensitive mRNA splicing cascade that transduces changes in ambient temperature into differential expression of the fundamental spliceosome component, ATU2AF65A . CDKG1 is alternatively spliced in a temperature‐dependent manner. We found that this process is partly dependent on both the cyclin‐dependent kinase G2 (CDKG2) and the interacting co‐factor CYCLIN L1 (CYCL1), resulting in two distinct messenger RNAs. The relative abundance of both CDKG1 transcripts correlates with ambient temperature and possibly with different expression levels of the associated protein isoforms. Both CDKG1 alternative transcripts are necessary to fully complement the expression of ATU2AF65A across the temperature range. Our data support a previously unidentified temperature‐dependent mechanism based on the alternative splicing (AS) of CDKG1 and regulated by CDKG2 and CYCL1. We propose that changes in ambient temperature affect the relative abundance of CDKG1 transcripts, and this in turn translates into differential CDKG1 protein expression coordinating the AS of ATU2AF65A . Significance Statement: One of the most important challenges of modern agriculture is the production of plant varieties that are better adapted to the predicted climatic changes. However, a deep understanding of the ambient temperature response in plants remains incomplete. Here we describe a gene circuit in the cyclin‐dependent kinase family of Arabidopsis able to modulate the activity of downstream targets by adjusting mRNA processing to ambient temperature.