Through the funding opportunity described in PAR-18-591, this proposal seeks funds to purchase a real-time PCR system to analyze intracellular signaling mediated by TORC2 and PTEN. The goals of the grant are to investigate how cells sense extracellular chemical gradients and control their migration behaviors. First, we will determine how phosphorylated, GDP-bound RacE activates TORC2 to facilitate AKT phosphorylation at the leading end of migrating cells while GTP-bound RacE inhibits TORC2 at the trailing end. This will involve multiple experimental approaches, including cellular reconstitution using knockout cell lines, biochemical reconstitution of RacE-regulated TORC2 activity with purified proteins, protein interaction analyses at the single-molecule level in vitro, live imaging of cells, and structural analysis using X-ray crystallography. Second, we will decipher a key mechanism controlling human PTEN localization at the plasma membrane and nucleus. Third, we will determine the effects of the manipulation of PTEN localization on tumorigenesis in vivo using animal models.
Chemotactic cell migration is critical to many physiological processes, including embryonic development, wound healing, and immune responses. Also, altered chemotaxis is associated with many diseases, including cancer, asthma, arthritis, and atherosclerosis. The proposed studies will significantly advance our understanding of the mechanism of chemotaxis and promote the development of therapeutic interventions for chemotaxis-related diseases.
