Grant: Project Grant

In this study we will examine a complex protein that is able to conduct potassium and has a vital role in maintaining the normal resting activity of excitable tissues. This protein is made up of two or three subunits which greatly affect its behavior when they combine with it. The aims of the present work are to fully understand how the main protein subunit interacts with its partners to produce the activity that we observe in the human body. The approach proposed in this study is to express the individual genes that code for the human potassium ion channel, IKs, and its partner subunits and then study the complexes together in a cell-based system. The work will entail using special chemicals to bind the subunits together when they are exposed to ultraviolet light, and then subjecting them to rigorous analysis to find out the exact places where they bind together. Powerful mass spectrometry techniques combined with electrical analysis of the channel function will be used to identify and locate the exact sites in different parts of the ion channels that contribute to binding between the subunits and how those sites shift as the channel opens and closes. We will be the first group to use these kind of very detailed methods and specific binding method to understand how the partners in this channel complex work together. We expect to obtain completely new information about the relationships between these proteins that will allow us to construct a model of how they act in concert during the normal functioning of the channel complex.