Tubulin is a protein found in a variety of cells as a heterodimer composed of two smaller subunits called alpha-tubulin and beta-tubulin.   Tublin dimers bind in a head to tail fashion (beta at the head) forming linear protofilaments.  These protofilaments associate laterally forming hollow cylinderical tubes of diameter approximately 25 nm.  These tubes, labeled microtubles (MT), are an important part of the cytoskeleton which  seem to play a role of fundamental importance in  a variety of cellular processes.  These processes include transport phenomena, cellular organization, and cell division.  
 

Together with my students Jake Byrnes and Elisabeth Humphris, I have been developing a Monte-Carlo simulation  aimed at understanding the growth and behavior of MT. The current version of the simulation (written in C++) as well as the rendered graphics, were written by Elisabeth Humphris, who can be contacted via email at ehumphri@virtu.sar.usf.edu.
 

Underlying the formation of an MT network is a process called "dynamic instability," a term used to describe the stochastic switching experienced by individual MTs between periods of assembly and periods of disassembly. The switching process, the rate of assembly, and the rate of disassembly are determined by a number of local variables whose taxonomy is nowhere near complete. For more information on dynamic instability, try the link

 An introduction to dynamic instability

Our first simulations involving models for MT dynamics during interphase. These results will soon include simulations for protein transport along MT. To see the pretty pictures as well as a few comparisons with other simulations, follow the link Model results/predictions for interphase

As the cell enters mitosis, MT play a critical role in positioning organelles for successful division. This is in large part affected through the formation of the mitotic spindle. Our results concerning spindle formation and dynamics will soon appear at this link: Model results/predictions for early mitosis