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Updated: May 15, 2026
08:57
Aip1p Dynamics Are Altered by the R256H Mutation in Actin
Published on: July 30, 2014
ARHGAP18 complexes with both YAP and Merlin and is required for basal actin bundles
Emma C Murray1, Gillian M Hodge1, Khanh Pham2
1Department of Biochemistry, State University of New York at Buffalo, Buffalo 14203 NY.
Molecular Biology of the Cell
|May 13, 2026
Summary
The Hippo and RhoA pathways coordinate cell structure. ARHGAP18 links these pathways, and its loss disrupts the actin cytoskeleton and cell signaling.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Cytoskeletal filament organization relies on signaling cascades.
- Rho family GTPases and the Hippo pathway are key regulators of the actin cytoskeleton.
- These pathways influence cell morphology, actin structures, and are implicated in cancer progression.
Purpose of the Study:
- Investigate the interplay between Hippo and Rho Family signaling pathways in human epithelial cells.
- Characterize the role of ARHGAP18 in connecting these two signaling networks.
- Elucidate the impact of ARHGAP18 loss on cytoskeletal organization and YAP localization.
Main Methods:
- CRISPR/CAS9 gene editing to knockout ARHGAP18.
- Super-resolution STORM microscopy to analyze cytoskeletal changes at the single-filament level.
- Co-immunoprecipitation to identify protein complex formation.
Main Results:
- ARHGAP18 forms a complex with Hippo pathway components Merlin (NF2) and YAP.
- Loss of ARHGAP18 leads to actin cytoskeleton alterations.
- ARHGAP18 knockout results in RhoA signaling dysregulation and aberrant nuclear YAP localization.
Conclusions:
- ARHGAP18 acts as a crucial link between RhoA and Hippo signaling pathways.
- Coordinated regulation of the actin cytoskeleton by Hippo and Rho GTPase signaling is supported.
- Findings provide insights into cytoskeletal control and potential cancer mechanisms.
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