ERAMOSA controls lateral branching in snapdragon

Area of Science:

• Plant developmental biology
• Genetics
• Evolutionary biology

Background:

• Plant architecture is determined by axillary meristems (AMs).
• The LATERAL SUPPRESSOR (Ls) gene, a GRAS transcription factor, is crucial for AM determination in model plants.
• Understanding AM regulation is key to controlling plant form.

Purpose of the Study:

• To characterize the snapdragon orthologue of Ls, named ERAMOSA (ERA).
• To investigate ERA's role in AM formation during both vegetative and reproductive phases.
• To explore the evolutionary relationship between ERA and Ls.

Main Methods:

• Phylogenetic analysis of ERA and Ls.
• Analysis of gene synteny across species.
• Characterization of single and double mutants (era, squa).

Main Results:

• ERA is a phylogenetic orthologue of Ls, playing a broader role in snapdragons.
• ERA controls AM formation during both vegetative and reproductive phases.
• During the reproductive phase, ERA is antagonized by SQUAMOSA (SQUA), and era squa double mutants exhibit a squa phenotype with AMs developing into flowers.

Conclusions:

• ERA is a key regulator of plant architecture and reproductive development in snapdragons.
• The interaction between ERA and SQUA highlights a complex regulatory network controlling meristem fate.
• ERA's broader role compared to Ls suggests evolutionary divergence in gene function.