X. Wang, et al., “Light-mediated activation reveals a key role for Rac in collective guidance of cell movement in vivo,” Nature Cell Biology, 12:591–98, 2010. http://bit.ly/Raclight
When Denise Montell and her team at the Johns Hopkins School of Medicine engineered an actin cytoskeleton-regulating protein to be light sensitive, they discovered it could also control cellular movement in vivo. When they shone light on one part of the cell, the Rac protein changed conformation into the active state and the cell, along with its surrounding cells, would move towards the direction of the activated Rac.
“This paper is among the first to delve into the mysterious molecular mechanics of collective cell movement,” writes Faculty Member Jonathan Chernoff in his review. When Montell used blue light to activate Rac in just one cell, the...
Surprisingly, there were some regions of the ovary into which the cells couldn’t migrate, even when Rac was activated and guiding them there, implying that “a dizzying array of endogenous signals” may affect cell migration in vivo, says Montell.
The lab is now investigating how the Rac signal is communicated between the cells in the group. Montell also plans to look at whether Rac and other photo-activatable proteins could be useful in the clinic, specifically to steer modified adult stem cells to particular tissues in need of repair.
F1000 evaluators: S. Hopkinson and J. Jones (Northwestern Univ. Medical School) •
E. Papusheva and C.P. Heisenberg (Max-Plank-Inst. for Molecular Cell Biology and Genetics) • J. Chernoff (Fox Chase Cancer Center)