Assessing the critical period for Rho kinase activity during Drosophila ventral furrow formation
Article first published online: 25 SEP 2012
Copyright © 2012 Wiley Periodicals, Inc.
Volume 241, Issue 11, pages 1729–1743, November 2012
How to Cite
Krajcovic, M. M. and Minden, J. S. (2012), Assessing the critical period for Rho kinase activity during Drosophila ventral furrow formation. Dev. Dyn., 241: 1729–1743. doi: 10.1002/dvdy.23859
- Issue published online: 17 OCT 2012
- Article first published online: 25 SEP 2012
- Accepted manuscript online: 12 SEP 2012 02:26PM EST
- Manuscript Accepted: 21 AUG 2012
- NSF. Grant Number: 0919769
- NIH. Grant Number: S10-RR024716
- ventral furrow formation;
- time-lapse microscopy;
- Rho kinase;
Background: Drosophila ventral furrow formation (VFF), which is the first morphogenetic event during embryo development, serves as a model for epithelial sheet folding. VFF can be subdivided into five cell shape changes: apical membrane flattening, apicobasal nuclear migration, apicobasal cell shortening, random apical constriction, and concerted apical constriction. These processes are generally believed to be driven by Rho kinase (Rok) activation of myosin II to stimulate the constriction of the apical actomyosin network. To test the role of Rok and its downstream target myosin II in VFF, timed injections of the Rok inhibitor, Y-27632, were performed. Results: Embryos injected with Y-27632 before the concerted apical constriction phase of VFF were able to execute apicobasal nuclear migration and random apical constriction, but were unable to enter the concerted apical constriction phase. Embryos injected with Y-27632 during concerted apical constriction reverted to the transition point between random apical constriction and concerted apical constriction. Finally, embryos injected with Y-27632 upon the initiation of furrow ingression were able to complete VFF. Conclusions: Together these results suggest a critical period for Rok activity and presumably myosin II activation during the initiation of the concerted apical constriction phase of VFF. Developmental Dynamics 241:1729–1743, 2012. © 2012 Wiley Periodicals, Inc.