Modeling human disease in yeast: recreating the PI3K-PTEN-Akt signaling pathway in Saccharomyces cerevisiae.

The yeast Saccharomyces cerevisiae is a model organism that has been thoroughly exploited to understand the universal mechanisms that govern signaling pathways. Due to its ease of manipulation, humanized yeast models that successfully reproduce the function of human genes permit the development of highly efficient genetic approaches for molecular studies. Of special interest are those pathways related to human disease that are conserved from yeast to mammals. However, it is also possible to engineer yeast cells to implement functions that are naturally absent in fungi. Along the years, we have reconstructed several aspects of the mammalian phosphatidylinositol 3-kinase (PI3K) pathway in S. cerevisiae. Here, we briefly review the use of S. cerevisiae as a tool to study human oncogenes and tumor suppressors, and we present an overview of the models applied to the study of the PI3K oncoproteins, the tumor suppressor PTEN, and the Akt protein kinase. We discuss the application of these models to study the basic functional properties of these signaling proteins, the functional assessment of their clinically relevant variants, and the design of feasible platforms for drug discovery.