RUI:The Paradox of Cellular Calcium Homeostasis During Vectorial Transfer: Spatial and Temporal Regulation of Ca Import/Export Proteins Using the Freshwater Crayfish Molting Model.

Wright State University, Dayton OH

Investigators

Abstract

Calcium (Ca) is critical to many processes in living organisms. Calcium enters the body through specialized cells (epithelia, like the gut or gills); from that point it must be redirected as needs dictate away from regions of low concentration (cytosol or cell interior) towards regions of high use (for example biomineralization zones that are extracellular or outside of cells). Calcium is moved within and between cells across internal and external membranes through the activity of an array of Ca transporting proteins (Ca channels, pumps and exchangers). Calcium transporting epithelia present the ultimate paradox, namely, how can vast amounts of Ca move through the cell while cytosolic levels are kept low? Using cellular and molecular approaches, the freshwater crayfish molting model will be used to study how these Ca transporting proteins are regulated over time (comparing periods of high Ca flux that occur just before and after molting, with periods of Ca balance during intermolt periods). Spatial regulation will also be studied by comparing activity of proteins on internal vs. external membranes. The goal of this work is to better understand how arrays of different Ca transporting proteins are regulated to achieve cellular Ca homeostasis. This research will advance the basic understanding of membrane Ca transport which has the potential to impact many branches of biomedicine. It will also result in student training at both graduate and undergraduate levels at two primarily undergraduate institutions and will be translated into the K-12 curriculum that is consistent with National Science Education Standards.