Abstract
Efficient collective migration depends on a balance between contractility and cytoskeletal rearrangements, adhesion, and mechanical cell-cell communication, which are all controlled by GTPases of the RHO family. Here, we report the results of a comprehensive screen assessing the contributions of the guanine nucleotide exchange factors (GEFs) to the regulation of this process during the wound healing response of a scratched human bronchial epithelial cell monolayer. Our studies uncovered GEFs that are required for collective motility at large, such as SOS1 and β-PIX, and RHOA GEFs ARHGEF18, ARHGEF11, ARHGEF3 and ARHGEF28 that are implicated in intercellular communication. Downregulation of these GEFs differentially enhance front-to-back propagation of guidance cues through the cell monolayer. These effects are partially mirrored by downregulation of RHOA expression and myosin-II activity. We conclude that for effective collective migration the RHOA-GEFs/RHOA/actomyosin pathway must be optimally tuned to compromise between generation of motility forces and restriction of intercellular communication.
Footnotes
↵& Deceased, May 3rd, 2015.
Abbreviations List
- GEF
- guanine nucleotide exchange factors
- GDI
- guanine dissociation inhibitors
- 16HBE
- human bronchial epithelial cells from the 16HBE14o line
- PCA
- principal component analysis
- PC
- principal components
- shRNA
- small hairpin RNA
- KD
- knockdown
- FBS
- fetal bovine serum
- PCR
- polymerase chain reaction
- qPCR
- quantitative PCR
- ROI
- region of interest