Abstract

The establishment of meristematic domains with different transcriptional activity is essential for many developmental processes. The asymmetry of the Antirrhinum majus flower is established by transcription factors with an asymmetric pattern of expression and activity. To understand how this asymmetrical pattern is established, we are studying the molecular mechanism through which the dorsal MYB protein RAD restricts the activity of the MYB transcription factor DIV to the ventral region of the flower meristem. We have shown that RAD antagonises DIV in a subcellular competition for a DRIF protein by inhibiting the interaction between DIV and DRI Fs in the dorsal regions of the Antirrhinum flower.

The interaction dynamics between RAD , DIV and DRIF homologues are conserved in other angiosperms. To further understand how the interactions between these three MYB -like proteins was first established and how this regulatory network has evolved, we are currently studying the evolutionary history of the interactions between RAD , DIV and DRIF homologues from distantly-related plant species.