Online

Naughton, Hannah

Cellular, Molecular, and Biomedical Sciences Graduate Program

2018

M.S.

Protein kinase A (PKA) regulates a diverse array of cellular activities including metabolism, differentiation, actomyosin contractility, and migration. The multifunctionality of this ubiquitous enzyme is achieved, in part, through subcellular targeting mediated by the A Kinase Anchoring Proteins (AKAP) family of proteins. AKAPs serve as scaffolding proteins that localize PKA to various cellular compartments and bring together specific targets and modulators of PKA activity. The importance of spatially restricted PKA signaling is particularly apparent in the context of cell motility. It has been observed that both anchoring through AKAPs and the subsequent localized activation of PKA at the leading edge of migrating cells are required for directed migration in multiple cell types. Despite the significant body of evidence linking PKA to the regulation of cellular adhesion, contractility, and migration, the mechanisms governing the spatiotemporal control of PKA signaling during these activities is not fully understood. Focal adhesion complexes, which connect the actin cytoskeleton to the extracellular matrix and are thus intimately involved in the adhesive and contractile state of the cell, are attractive potential sites of PKA signaling. We have evidence indicating that PKA is active within these complexes, and that this activity impacts focal adhesion dynamics. To address the question of how PKA may be recruited to adhesive complexes, we have developed a targeted screen to identify PKA interacting proteins within adhesive and cytoskeletal structures. This method utilizes proximity-dependent biotin labeling in combination with a focal adhesion purification preparation and downstream proteomic analysis. The results of this screen will be used to identify candidate AKAPs and will serve as the foundation for future inquiry into the complex role of PKA in the regulation of cell migration.