Using sophisticated fluorescence microscopy, polymerization of single actin filaments can now be observed directly. Recent experiments show that the ends of actin filaments grow and shorten more rapidly than would be predicted from measured rate constants for monomer association and dissociation. This suggests that actin filaments may undergo a type of dynamic instability, similar to microtubules, or even use a previously uncharacterized mechanism to drive filament turnover.
- Ryan Littlefield
- Velia M. Fowler