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10:41
Tracking and Quantifying Developmental Processes in C. elegans Using Open-source Tools
Published on: December 16, 2015
Distinct cell guidance pathways controlled by the Rac and Rho GEF domains of UNC-73/TRIO in Caenorhabditis elegans
Nancy Marcus-Gueret1, Kristopher L Schmidt, Eve G Stringham
1Department of Biology, Trinity Western University, Langley, BC V2Y 1Y1, Canada.
Genetics
|October 15, 2011
Summary
The cytoskeleton regulators UNC-53/NAV2 and VAB-8 control excretory canal outgrowth in C. elegans through parallel pathways. UNC-73/TRIO acts as a crucial molecular switch, integrating these pathways for proper canal extension.
Area of Science:
- Cell biology
- Developmental biology
- Neuroscience
Background:
- The cytoskeleton plays a critical role in cell migration and outgrowth.
- Neuronal guidance cues and motor proteins are essential for directed cell movement.
- Understanding the molecular mechanisms of canal extension is key to developmental processes.
Purpose of the Study:
- To elucidate the genetic pathways regulating posterior excretory canal outgrowth in C. elegans.
- To investigate the roles of UNC-53/NAV2 and VAB-8 in canal extension.
- To determine how UNC-73/TRIO integrates different signaling pathways.
Main Methods:
- Genetic analysis of null mutants and double mutants in C. elegans.
- Cell-specific rescue experiments to determine pathway interactions.
- Analysis of gene interactions including UNC-53, VAB-8, SAX-3/ROBO, SLT-1/Slit, EVA-1, UNC-71/ADAM, and UNC-73/TRIO.
Main Results:
- UNC-53 and VAB-8 function in parallel pathways to promote posterior excretory canal outgrowth.
- VAB-8, SAX-3/ROBO, SLT-1/Slit, and EVA-1 function together in one pathway.
- UNC-53 functions in a parallel pathway with UNC-71/ADAM.
- UNC-73/TRIO acts as a bipartite regulator, with distinct isoforms mediating cell-autonomous and cell-nonautonomous functions.
Conclusions:
- A bipartite model for UNC-73/TRIO activity in excretory canal extension is proposed.
- UNC-73/TRIO integrates signals from UNC-53/NAV2 and VAB-8 pathways.
- This study reveals a complex regulatory network controlling directed cell outgrowth.
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