Rice early flowering1, a CKI, phosphorylates DELLA protein SLR1 to negatively regulate gibberellin signalling

The plant hormone gibberellin (GA) is crucial for multiple aspects of plant growth and development. To study the relevant regulatory mechanisms, we isolated a rice mutant e arlier f l owering1 , el1 , which is deficient in a casein kinase I that has critical roles in both plants and animals. el1 had...

Full description

Saved in:
Bibliographic Details
Published in:The EMBO journal 2010-06, Vol.29 (11), p.1916-1927
Main Authors: Dai, Cheng, Xue, Hong-Wei
Format: Article
Language:English
Subjects:
Botany
casein kinase I
EL1
EMBO13
EMBO30
flowering time
GA response
Gibberellins - genetics
Gibberellins - metabolism
Gibberellins - pharmacology
Hormones
Molecular biology
Mutation
Oryza - genetics
Oryza - growth & development
Oryza - metabolism
Oryza sativa
Phosphorylation
Plant growth
Plant Growth Regulators - genetics
Plant Growth Regulators - metabolism
Plant Growth Regulators - pharmacology
Plant Proteins - genetics
Plant Proteins - metabolism
Plant Proteins - pharmacology
Rice
Signal Transduction - drug effects
Signal Transduction - genetics
Signal Transduction - physiology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The plant hormone gibberellin (GA) is crucial for multiple aspects of plant growth and development. To study the relevant regulatory mechanisms, we isolated a rice mutant e arlier f l owering1 , el1 , which is deficient in a casein kinase I that has critical roles in both plants and animals. el1 had an enhanced GA response, consistent with the suppression of EL1 expression by exogenous GA 3 . Biochemical characterization showed that EL1 specifically phosphorylates the rice DELLA protein SLR1, proving a direct evidence for SLR1 phosphorylation. Overexpression of SLR1 in wild‐type plants caused a severe dwarf phenotype, which was significantly suppressed by EL1 deficiency, indicating the negative effect of SLR1 on GA signalling requires the EL1 function. Further studies showed that the phosphorylation of SLR1 is important for maintaining its activity and stability, and mutation of the candidate phosphorylation site of SLR1 results in the altered GA signalling. This study shows EL1 a novel and key regulator of the GA response and provided important clues on casein kinase I activities in GA signalling and plant development.
ISSN:0261-4189
1460-2075
DOI:10.1038/emboj.2010.75