Function and Evolution of Grass B Class Floral Homeotic Proteins

Brigham Young University, Provo UT

Investigators

Abstract

Clinton Whipple IOS-1025121 Function and Evolution of Grass B Class Floral Homeotic Proteins Flowers have a characteristic arrangement of organs that is consistent throughout all of flowering plants (angiosperms). Early in flower development, a group of related proteins, known as MADS-box proteins, plays a key role in establishing the correct organ identity for each whorl. Stamen (male reproductive structures) and petal identities, for example are controlled by the combined activity of two distinct MADS-box proteins, known as the B class proteins. These two B class proteins, which are found in all angiosperm lineages, have been shown to function only when both are present in some groups of angiosperms, while in other groups the proteins appear to function without a partner. It is not clear what these proteins are doing when they act without a partner, nor is it clear how distinct angiosperm groups evolved so that their B class proteins either function alone or in combination. This project will investigate the function and evolution of B class protein interaction in the grass family, which has B class proteins that must act together. A mutant in which a grass B class protein is disrupted will be characterized to understand its function in the grass family. B class proteins will be isolated from diverse grass members and closely related grasses. These proteins will then be assayed for their ability to act alone or with their respective partners in order to understand the point at which grasses evolved the requirement for both partners. The protein sequences will be assayed for evidence of natural selection that may have facilitated this evolution. Ultimately, the precise protein modifications that allowed the evolution of these interesting protein interactions will be elucidated by this research. The project will provide training for a postdoctoral associate, graduate student and several undergraduates. In addition, local high school student will be involved by creation of a novel module to investigate the ethical implications of transgenic crop technologies.