Next SolSeminar will be presented by Elizabeth McCarthy on The evolution of flower color in Nicotiana allopolyploids: From pigments to genes to modeling
Abstract. Allopolyploidy, which involves both hybridization and genome duplication, has played a predominant role in the evolution of angiosperms. Allopolyploids from the same origin often have divergent phenotypes, which can even be transgressive, or outside the range observed in the progenitors. Elizabeth study the effects of allopolyploidy on the evolution of flower color in Nicotiana (tobacco). Nicotiana is an excellent genus in which to evaluate these questions because it displays variation in flower color, and approximately half of the species are allotetraploids of different ages, including N. tabacum (0.6 million years old) and section Repandae (~4.3 million years old). Quantification of flavonol and anthocyanin pigments show that differences in cyanidin concentration underlie light pink and dark pink flowers of N. tabacum accessions and revealed transgressive delphinidin pigment in two species of section Repandae. Transcriptome analyses have determined that the genetic basis of light pink flowers in N. tabacum seems to be delayed expression of the Dihydroflavonol-4-reductatse (DFR) gene, which encodes for an enzyme that synthesizes anthocyanins. Evolutionary simulations suggest that mutations in the genes at branch points of the flavonoid biosynthetic pathway are necessary to induce floral color shifts and that some floral color shifts are more difficult to evolve than others.
When? Friday Nov 5th 4 pm (GMT+1)
The zoom link to join the meeting is https://cuboulder.zoom.us/j/94333146166 Meeting ID: 943 3314 6166, password: Solanaceae
Watch this talk in TouTube: https://youtu.be/C9SykZNAsF8