Yeast System as a Screening Tool for Pharmacological Assessment of G Protein Coupled Receptors

Abstract

G-protein-coupled receptors (GPCRs) constitute the largest but the most divergent class of cell surface proteins. Although they are thought to share a common 3D-structure composed of seven transmembrane helical domains, they can be activated by extracellular signals as diverse as light, peptides, proteins, lipids, organic odorants, taste molecules, nucleotides or nucleosides. They are involved in an extraordinarily large number of physiological functions and are therefore potential drug targets for many human diseases. During the last decade various GPCRs have been successfully expressed in S. cerevisiae. Yeast is an attractive expression system because it offers the genetic engineering tools typical of a microorganism while possessing an eukaryotic type of secretory pathway and post-translational machinery. This host is particularly attractive for in-vivo manipulation of these receptors due to the high homology between the yeast pheromone signaling pathway and that of mammalian GPCRs. When expressed in yeast, mammalian GPCRs have been shown to couple functionally to either the endogenous yeast Galpha (Gpa1), or co-expressed mammalian Galpha subunits (wild-type or chimeric), and are characterized by a similar pharmacology in response to agonists or antagonists as in native cells. Heterologous expression of wild type or mutant GPCRs in S. cerevisiae allows a rapid assessment of their ability to detect and transduce extracellular stimulations, through the use of a reporter system. Furthermore, this approach is amenable to high-throughput screening of new drugs, which would provide a determinant advantage in the field of therapeutic research, and also for investigation of the still unknown ligands of orphan receptors. This review will focus on the latest developments of yeast-based technology to screen for potential GPCR agonists/antagonists.

The KlSTE2 and KlSTE3 genes encode MATα‐ and MATa‐specific G‐protein‐coupled receptors, respectively, which are required for mating of Kluyveromyces lactis haploid cells

“…During the last decade various GPCRs have been successfully expressed in S. cerevisiae (Minic et al, 2005). Yeast is an attractive expression system because it offers the genetic engineering tools typical of a microorganism, while possessing an eukaryotic type of secretory pathway and post-translational machinery.…”

Quantitative Structure-Activity Relationships (QSARs) of Monoterpenoids at an Expressed American Cockroach Octopamine Receptor

“…Saccharomyces cerevisiae, referred to as yeast hereafter, has emerged as an important organism for the study of heterologously expressed GPCRs (21,22). Functional expression of heterotrimeric GPCRs can be achieved by linking the expressed receptor to the endogenous pheromone response pathway, which has been performed for analysis of multiple mammalian GPCRs (22) and some invertebrate GPCRs (23)(24)(25). Previously, we have reported the expression of Pa oa1 in yeast, which resulted in a ligand-independent (constitutive) expression system (25).…”

Fungal sensing of host environment

“…Because it was found that pH-sensing pathways also control the expression of virulence traits not directly associated with pH, including adhesion to host cells and tissue invasion (Davis, 2009), further studies would be warranted. Because of the high homology between the yeast pheromone signalling pathway and that of mammalian GPCRs and their easy genetic modulation, they were even used in reporter assays to screen for new drugs targeting GPCRs (Minic et al, 2005), thus underlining the evolutionary conserved use of GPCRs for sensing and signalling of distinct cues among kingdoms.…”