Poster

         Phytochemical

Re-examining the functional significance of betalains

Presenting Author
George Garnett
Description
Specialised metabolites are common in plants, with many of these compounds conferring some fitness benefit to the individuals that produce them. My work focusses on two plant specialised metabolites: anthocyanins and betalains. Together, these pigments are responsible for much of the red colouration visible in plants. Despite their similar appearance, there are important differences between these two pigments. Anthocyanins are ubiquitous in plants; contrastingly, betalains are rare, being found only in the order Caryophyllales where they have evolved convergently up to four times. Curiously, betalains and anthocyanins are mutually exclusive, having never been found to co-occur. Some have attributed this to functional redundancy; however, the role of betalains in plants is poorly understood. The replacement of anthocyanins with betalains in some members of the Caryophyllales could suggest that betalains possess novel adaptive advantages over anthocyanins that favoured their repeated recruitment. My research seeks to better understand the functional significance of betalains, using several interdisciplinary approaches. This knowledge should reveal the extent to which natural selection played a role in the convergent evolution of betalains. It is hoped this will improve our understanding of the evolutionary forces that drive convergence more generally; in turn helping to answer a fundamental biological question – how repeatable is evolution?