Petal size is controlled by the MYB73/TPL/HDA19-miR159-CKX6 module regulating cytokinin catabolism in Rosa hybrida.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 37925502.
- Also identified by DOI 10.1038/s41467-023-42914-y and PMC identifier 10625627.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The size of plant lateral organs is determined by well-coordinated cell proliferation and cell expansion. Here, we report that miR159, an evolutionarily conserved microRNA, plays an essential role in regulating cell division in rose (Rosa hybrida) petals by modulating cytokinin catabolism. We uncover that Cytokinin Oxidase/Dehydrogenase6 (CKX6) is a target of miR159 in petals. Knocking down miR159 levels results in the accumulation of CKX6 transcripts and earlier cytokinin clearance, leading to a shortened cell division period and smaller petals. Conversely, knocking down CKX6 causes cytokinin accumulation and a prolonged developmental cell division period, mimicking the effects of exogenous cytokinin application. MYB73, a R2R3-type MYB transcription repressor, recruits a co-repressor (TOPLESS) and a histone deacetylase (HDA19) to form a suppression complex, which regulates MIR159 expression by modulating histone H3 lysine 9 acetylation levels at the MIR159 promoter. Our work sheds light on mechanisms for ensuring the correct timing of the exit from the cell division phase and thus organ size regulation by controlling cytokinin catabolism.
Medical subject headings
- Rosa