Developmental Genetics of Pollinator-Associated Floral Traits

Most flowering plants rely on animal pollination for reproductive success. However, the genes and developmental networks regulating many of the pollinator-associated floral traits (e.g., carotenoid pigmentation, corolla tube formation and elaboration, stamen and pistil arrangement, nectar volume, etc.) remain poorly understood, largely because the conventional genetic model system, Arabidopsis, is not particularly suitable to study these traits. To address this problem, we have developed a new genetic model system, Mimulus lewisii (monkeyflower). In the past few years we have initiated a large-scale ethyl methanesulfonate (EMS) mutagenesis experiment in M. lewisii, and have recovered many remarkable floral mutants; we have generated a wealth of genomic resources that enabled rapid identification of culprit genes underlying the EMS mutants; we have also established an efficient in planta transformation system for M. lewisii, which allows transgenic experiments to be performed to rigorously characterize gene function and developmental processes. In this talk I will give an example on the identification of the first transcription factor regulating floral carotenoid pigmentation, to communicate our beginning progress towards understanding the developmental genetics of these pollinator-associated floral traits.