Evolutionary variation in MADS-box dimerization affects floral development and protein abundance in maize
Bartlett, Madelaine; Abraham-Juarez, Jazmin; Schrager-Lavelle, Amanda (2020), Evolutionary variation in MADS-box dimerization affects floral development and protein abundance in maize, Dryad, Dataset, https://doi.org/10.5061/dryad.4xgxd2573
Interactions between MADS-box transcription factors are critical in the regulation of floral development, and shifting MADS-box protein-protein interactions are predicted to have influenced floral evolution. However, precisely how evolutionary variation in protein-protein interactions affects MADS-box protein function remains unknown. To assess the impact of changing MADS-box protein-protein interactions on transcription factor function, we turned to the grasses, where interactions between B-class MADS-box proteins vary. We tested the functional consequences of this evolutionary variability using maize as an experimental system. We found that differential B-class dimerization was associated with subtle, quantitative differences in stamen shape. In contrast, differential dimerization resulted in large-scale changes to downstream gene expression. Differential dimerization also affected B-class complex composition and abundance, independent of transcript levels. This indicates that differential B-class dimerization affects protein degradation, revealing an important consequence for evolutionary variability in MADS-box interactions. Our results highlight complexity in the evolution of developmental gene networks - changing protein-protein interactions could affect not only the composition of transcription factor complexes, but also their degradation and persistence in developing flowers. Our results also show how coding change in a pleiotropic master regulator could have small, quantitative effects on development.
National Science Foundation, Award: IOS-1652380
National Science Foundation, Award: IOS-1546837
U.S. Department of Agriculture, Award: NIFA-2018-67012-27998