John H. Carson

This laboratory is investigating intracellular trafficking of mRNA in cells of the nervous system using a combination of molecular biological, microinjection, confocal microscopy and three dimensional visualization techniques. We have delineated an RNA trafficking pathway consisting of export from the nucleus, granule assembly in the perikaryon, transport of RNA granules in the processes, localization to the distal regions of the cell and translational activation. We are analyzing the cis/trans regulation of each step in this pathway and have identified a common 21 nucleotide RNA trafficking signal (RTS) in many different transported mRNAs that binds specifically to hnRNPA2 and is involved at various steps in the trafficking pathway. The laboratory is also investigating expression and intracellular trafficking of the gap junction protein, connexin 32, in oligodendrocytes using green fluorescent protein fusions, time lapse confocal imaging, and three dimensional visualization. The laboratory is also involved in developing a comprehensive computational simulation of cellular physiology and behavior. This project, termed the Virtual Cell, consists of a multidisciplinary team of cell biologists, molecular biologists, mathematicians, physicists, computer scientists, engineers and programmers. One goal of the project is to model the intracellular RNA trafficking pathway we have outlined.