miR394 and LCR cooperate with TPL to regulate AM initiation
Liya Liu1,2, Binbin Hu1,2, Siying Guo1,2
1Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
Nature Communications
|November 23, 2024
Summary
MicroRNAs regulate plant architecture by controlling axillary bud initiation. miR394 promotes bud formation by targeting LEAF CURLING RESPONSIVENESS (LCR), which degrades TOPLESS (TPL) proteins, influencing crop yield.
Area of Science:
- Plant biology
- Molecular genetics
- Crop science
Background:
- Plant architecture, particularly lateral branching, is crucial for crop yield.
- The precise molecular mechanisms governing axillary bud initiation are not fully understood.
Purpose of the Study:
- To elucidate the role of microRNAs (miRNAs) in regulating axillary bud initiation.
- To identify key molecular players and pathways involved in this process.
Main Methods:
- Small RNA library construction and mutant screening.
- Promoter-driven fluorescent tagging and in situ hybridization.
- Molecular and genetic analyses, including immunoprecipitation-mass spectrometry.
Main Results:
- Axillary bud initiation is induced by miR394 and repressed by its target, LEAF CURLING RESPONSIVENESS (LCR).
- miR394 is localized to the leaf axil where axillary meristems (AMs) initiate.
- The miR394/LCR pathway regulates REVOLUTA (REV) and SHOOT MERISTEMLESS (STM) genes.
- LCR, an F-box protein, interacts with TOPLESS (TPL) proteins, promoting ubiquitinated protein degradation.
Conclusions:
- miR394-mediated regulation of LCR accelerates TPL degradation, precisely controlling axillary bud initiation.
- This mechanism is vital for establishing the axillary meristem and influencing plant architecture and crop yield.
