AUTHOR=Le Maitre N C , Pirie Michael David , Bellstedt Dirk U. 

TITLE=Floral Color, Anthocyanin Synthesis Gene Expression and Control in Cape Erica Species

JOURNAL=Frontiers in Plant Science

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2019.01565

DOI=10.3389/fpls.2019.01565

ISSN=1664-462X

ABSTRACT=<p><bold>Introduction:</bold> The Cape Floristic Region (CFR) is a biodiversity hotspot, recognized globally for its unusually high levels of endemism. The origins of this biodiversity are a long-standing topic of research. The largest “Cape clade,” <italic>Erica</italic>, radiated dramatically in the CFR, its ca. 690 species arising within 10–15 Ma. Notable between- and within-species flower color variation in <italic>Erica</italic> may have contributed to the origins of species diversity through its impact on pollinator efficiency and specificity.</p><p><bold>Methods:</bold> We investigate the expression and function of the genes of the anthocyanin biosynthesis pathway that controls floral color in 12 <italic>Erica</italic> species groups using RT-qPCR and UPLC-MS/MS.</p><p><bold>Results:</bold> Shifts from ancestral pink- or red- to white- and/or yellow flowers were associated with independent losses of single pathway gene expression, abrogation of the entire pathway due to loss of the expression of a transcription factor or loss of function mutations in pathway genes.</p><p><bold>Discussion:</bold> Striking floral color shifts are prevalent amongst the numerous species of Cape <italic>Erica</italic>. These results show independent origins of a palette of mutations leading to such shifts, revealing the diverse genetic basis for potentially rapid evolution of a speciation-relevant trait.</p>