Something old, something new: Genome duplications and the origins of plant chemodiversity

PATRON_E21DTP2

Plants produce numerous biologically active, specialized metabolites, which vary in structure, biosynthesis, and contribute to adaptation to their ecological niches. Novel metabolites can arise through metabolic pleiotropy, expansions and contractions of enzyme specificity as well as through gene duplication followed by neofunctionalization.

Whole genome duplication (polyploidization), common in many lineages of flowering plants, leads to a sudden increase in genome size and gene number. Subsequent largeā€scale chromosome rearrangements and complex patterns of gene loss are known to result in extensive alterations to the genome, providing considerable opportunities for metabolic plasticity. This is proposed to increase the chances of success in strongly fluctuating environments and/or enable plants to effectively colonize new habitats.

The aster family (Asteraceae) is one of the largest plant families with over 25,000 species, many of which have been cultivated for the medicinal properties of their specialized metabolites. Numerous polyploidy events have been identified within the Asteraceae. In some genera, different ploidy levels have been reported between species, while some also show ploidy variation between individuals of the same species (i.e. intraspecific ploidy variation). Working between the Earlham Institute (Norwich Research Park) and the Royal Botanic Gardens at Kew, this project will investigate the impact of polyploidization on plant specialized metabolism, exploring the genetic basis of metabolic diversity following genome duplication in species of medicinal interest. The project integrates data generated using a range of technologies including bioinformatics, biochemistry and molecular biology. Training will be provided in all techniques.

References:
Mandel et al (2019) A fully resolved backbone phylogeny reveals numerous dispersals and explosive diversifications throughout the history of Asteraceae PNAS 116(28);14083-14088

Pellicer et al (2018) Genome size diversity and its impact on the evolution of land plants Genes 9(2);8