BioEnv-seminar: “When nature changed its colours: the evolutionary rise of betalain”

Short abstract
The evolution of betalains - best known as the pigments responsible for the colour of beetroot - represents a highly unusual evolutionary event within the flowering order Caryophyllales. This transition involved not only the emergence of an entirely new biosynthetic pathway for pigment production, but also the complete replacement of the anthocyanin pigments, which have otherwise dominated plant coloration for 100’s of millions of years. The rise of betalains has had profound implications for the ecology and evolution of Caryophyllales, influencing everything from floral colour diversity to the structural organisation of plant genomes. In this talk, I will outline how our understanding of the evolutionary trajectories of both the betalain and anthocyanin pathways has been transformed through advances in genomics, combined with synthetic biology. I will explore key mechanisms underlying this transition, including modulation at the interface between primary and secondary metabolism, the role of gene duplication, and growing evidence for multiple convergent origins of betalain pigmentation within Caryophyllales. In light of this emerging evidence, I will revisit hypotheses about the evolution of betalains and consider new perspectives on their adaptive significance, including intriguing biochemical links to the infamous hallucinogen mescaline.