Evolutionary walks through flower color space driven by gene expression in Petunia and allies (Petunieae)
Year: 2023
Type: preprint
Abstract: The structure and function of biochemical and developmental pathways determine the range of accessible phenotypes, which are the substrate for evolutionary change. Accordingly, we expect that observed phenotypic variation across species is strongly influenced by pathway structure, with different phenotypes arising due to changes in activity along pathway branches. Here we use flower color as a model to investigate how the structure of pigment pathways shapes the evolution of phenotypic diversity. We focus on the phenotypically diverse Petunieae clade in the nightshade family, which contains nearly 200 species of Petunia and related genera, as a model to understand how flavonoid pathway gene expression maps onto pigment production. We use multivariate comparative methods to estimate co-expression relationships between pathway enzymes and transcriptional regulators, and then assess how expression of these genes relates to the major axes of variation in floral pigmentation. Our results indicate that coordinated shifts in gene expression predict transitions in both total anthocyanin levels and pigment type, which, in turn, incur trade-offs with the production of UV-absorbing flavonol compounds. These findings demonstrate that the intrinsic structure of the flavonoid pathway and its regulatory architecture underlies the accessibility of pigment phenotypes and shapes evolutionary outcomes for floral pigment production.
DOI: 10.32942/x2759x
Institution: University of Colorado Boulder
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
Awards: G2586609609, G2796167598, MRI Collaborative Consortium: Acquisition of a Shared Supercomputer by the Rocky Mountain Advanced Computing Consortium, G4958434179, MRI Collaborative Consortium: Acquisition of a Shared Supercomputer by the Rocky Mountain Advanced Computing Consortium, G5424111711, CAREER: Testing The Predictability of Flower Color Evolution at a Phylogenetic Scale in the Petunieae Clade (Solanaceae), CC* Compute: HPC Services for the Colorado State University System, G8929392486
OpenAlex ID: W4318946015