Sandia National Laboratories
Near or far: influential ion channel neighbors on the endoplasmic reticulum
Monday, April 3, 2006
3:00 p.m., Room 121
The spatial distributions of ionic transporters (and myriad other mechanisms) in biological cell systems and their impact on cellular function is of great interest. Localization of such transporters relative to each other and neighboring molecular machinery can significantly modulate cellular response. The endoplasmic reticulum (ER) is an intracellular organelle involved in maintenance of cytosolic calcium concentrations which determine a plethora of cellular activity. We present results from a model of a particular calcium ion channel, the inositol-triphosphate receptor (IP3R), in distinct spatial distributions on the surface of the ER and the resulting impact of these distributions on intraluminal ER calcium. The model is a reaction-diffusion representation approximated with unstructured finite element methods on a high-resolution reconstruction of an ER section. With all other aspects of the model equivalent, we show distinct spatial distributions of the IP3R vary release of calcium from the ER lumenal store.