This NSF award by the Biotechnology, Biochemical and Biomass Engineering program supports work to develop improved expression systems for integral membrane proteins. Integral membrane proteins play critical roles in cell signaling, and are implicated in a wide range of human diseases such as asthma, obesity, cancer, heart disease, and chronic pain. Biophysical and biochemical studies of membrane proteins require large quantities of purified protein; even more than soluble proteins, because they need to be solubilized in detergent solutions. Results for many classes of membrane proteins suggest that in traditional expression systems, valuable targets of drug discovery and biochemical importance will be understudied because researchers cannot make sufficient protein. The goal of this research effort is to improve the expression of an important class of membrane proteins, the G protein-coupled receptor family (GPCRs). Specific aims are to identify cellular and molecular features of both the proteins and expression host to achieve the highest level of active GPCRs for structural and biophysical characterization. In addition, specific educational examples will be developed for the undergraduate Heat and Mass Transfer course. Graduate and undergraduate students will be trained in the laboratory, with particular efforts focused on representation from women and under-represented groups.
Intellectual Merit: In the research supported by NSF CBET, we have examined the expression of a set of related adenosine receptors, a set of membrane proteins that play a key role in the response of the cell to the native compound adenosine, as well as caffeine. This role includes regulating oxygen consumption, blood flow, anti-inflammatory and immune responses, and these receptors are located throughout the body. In this research, we sought to improve levels of expression of a set of human adenosine receptors in yeast in order to facilitate improved characterization outside of the native environment to improve drug discovery efforts. To this end, we have developed methods to improve the expression of a previously poorly expressed adenosine receptor (A2b), and improved our understanding of the limitations to expression in any host cell of interest. In addition, we have developed a screening method that will enable us to examine the efficacy of new drug compounds in the yeast host. Broader Impact: Our research has led to seven peer-reviewed publications and dissemination through presentations and interaction at national meetings. Four PhD level scientists (two of which were women) have been supported throughout the grant period, and six undergraduate students (including four women and two under-represented minorities) have carried out research with their mentorship, increasing the diversity and quality of the STEM field.
