BIO315H5 Lecture Notes - Lecture 4: Hydrolysis, Phosphodiesterase, Rod Cell
Document Summary
G protein-coupled receptor (gpcr) and enzyme-coupled receptor signaling. Explain the role of protein conformational change in: When the gpcr gets activated it undergoes a conformational change allowing it to interact with the g protein, the g protein will release an alpha subunit causing another change that dissociates the beta and gamma subunits. When camp binds to the regulatory subunits they undergo a conformational change allowing the catalytic subunits to undergo a change. In cardiomyocytes, calcium waves have leading as well as trailing edges (front of the wave vs. back of the wave). Calmodulin is a protein that has no enzymatic activity. It binds to ca2+ --> acts as sensor for calcium levels in a cell. Conformational change in calmodulin allows it to interact with other proteins. Sometimes constantly bound to proteins that it regulates. Calmodulin-dependent protein kinases: decoding specific nature of calcium signal. Molecule that is important for the molecular memory of calcium significance in the cell.
