ARHGAP11A

ARHGAP11A is a Rho GTPase-activating protein that inactivates RhoA and controls actin cytoskeletal dynamics in contexts ranging from cortical neurogenesis to mitotic spindle orientation and directed cell migration (PMID:39389782, PMID:41307995). In developing cortex its mRNA is delivered to the basal endfeet of radial glial cells through its 5' UTR and locally translated, where it shapes endfoot morphology and positions interneurons at the basement membrane via local Rho signaling (PMID:36924763), while in apical progenitors it sustains progenitor identity and ventricular zone integrity through the RHOA-ROCK-actin axis, with its loss randomizing mitotic cleavage-plane orientation and depleting progenitors—defects rescued by RHOA or ROCK inhibition (PMID:41307995). The same RhoA-ROCK output is deployed in mitosis, where Haspin kinase channels signals through ARHGAP11A to engage ROCK-LIMK1-Cofilin and stabilize actin for proper spindle orientation and epithelial morphogenesis (PMID:37841592). ARHGAP11A protein levels are restricted by the hGID/GID4 E3 ubiquitin ligase, which ubiquitinates it for proteasomal degradation; relieving this degradation stabilizes ARHGAP11A at the cell periphery, where it inactivates RhoA and impairs directed migration (PMID:39389782). Beyond canonical GAP activity it engages additional partners—Rac1B in a GAP-independent manner to drive carcinoma malignancy (PMID:30545369) and TPM1 to regulate actin filament stability (PMID:34912455)—and acts as a context-dependent oncoprotein in basal-like breast cancer (PMID:27657701).

1. 2016 Medium

   Established that ARHGAP11A, despite being a RhoA GAP, functions as a context-dependent oncoprotein rather than a tumor suppressor, distinguishing it from canonical tumor-suppressive RhoA GAPs.

   Evidence Functional cell-based and expression assays across breast cancer subtypes

   PMID:27657701

   Open questions at the time

   • Molecular basis of oncogenic versus tumor-suppressive context not resolved
   • No direct substrate or partner mapping in this study
2. 2018 Medium

   Showed ARHGAP11A can act independently of its GAP activity, binding Rac1B to drive carcinoma malignancy, revealing a non-canonical effector mode.

   Evidence Co-IP, knockdown/overexpression in HCC lines, xenograft rescue

   PMID:30545369

   Open questions at the time

   • Structural basis of GAP-independent Rac1B binding unknown
   • Single lab; not extended to other tumor types
3. 2021 Medium

   Identified TPM1 as a physical partner linking ARHGAP11A to actin filament stability, connecting it to cytoskeletal regulation in cancer cell motility.

   Evidence Co-IP, knockout in vitro/in vivo, actin stability assays in gastric cancer

   PMID:34912455

   Open questions at the time

   • Whether TPM1 binding depends on GAP activity not resolved
   • Single binding partner; reciprocal validation limited
4. 2022 Low

   Reported post-transcriptional regulation by miR-211-5p targeting the Arhgap11a 3' UTR during osteoblast differentiation.

   Evidence Dual-luciferase reporter, miRNA mimic/inhibitor, RT-qPCR in MC3T3-E1 cells

   PMID:35495761

   Open questions at the time

   • Paradoxical miRNA-driven upregulation not mechanistically explained
   • Single lab; no functional link to Rho signaling demonstrated
5. 2023 High

   Demonstrated spatial control of ARHGAP11A through 5' UTR-dependent mRNA localization and local translation in radial glial basal endfeet, establishing it as a locally synthesized regulator of cortical progenitor morphology and neuronal positioning.

   Evidence In situ hybridization, 5' UTR reporters, transport inhibition, loss-of-function in mouse and human tissue

   PMID:36924763

   Open questions at the time

   • Identity of the transport machinery recognizing the 5' UTR unknown
   • Local Rho effectors at endfeet not enumerated
6. 2023 Medium

   Placed ARHGAP11A within a mitotic Haspin-Rho-ROCK-LIMK1-Cofilin axis required for spindle orientation and 3D epithelial morphogenesis, linking it to cell-cycle cytoskeletal control.

   Evidence Genetic epistasis, kinase inhibition, 3D morphogenesis assays, phospho-LIMK1/Cofilin readouts

   PMID:37841592

   Open questions at the time

   • Direct biochemical link between Haspin and ARHGAP11A not shown
   • How ARHGAP11A is positioned at the spindle unknown
7. 2023 Medium

   Connected ARHGAP11A to amyloid-β pathology via a RhoA/ROCK/Erk pathway sustaining APP/PS1/BACE1, embedded in an E2F1-driven feed-forward loop.

   Evidence Neuronal knockdown in APP/PS1 mice, Western blot, behavior, E2F1 reporter assays

   PMID:37302068

   Open questions at the time

   • Whether GAP activity is required for the APP-axis effect not tested
   • Direct molecular target downstream of ARHGAP11A unclear
8. 2024 High

   Identified the hGID/GID4 E3 ligase as the degradative regulator of ARHGAP11A, showing that its abundance at the cell periphery sets the level of RhoA inactivation and directed migration.

   Evidence BioID2 proximity proteomics, ubiquitination assays, GID4 depletion/PFI-7 inhibitor, motility and localization imaging

   PMID:39389782

   Open questions at the time

   • Degron sequence recognized by GID4 not mapped
   • Upstream signals controlling GID4-mediated turnover unknown
9. 2025 High

   Showed in human cortical organoids that ARHGAP11A maintains apical progenitor identity and cleavage-plane orientation through the RHOA-ROCK-actin axis, with pharmacological RHOA/ROCK inhibition rescuing knockout defects.

   Evidence CRISPR-Cas9 KO in forebrain organoids, cleavage-plane measurements, RHOA/ROCK inhibitor rescue

   PMID:41307995

   Open questions at the time

   • How ARHGAP11A spatially restricts RhoA at the apical surface unknown
   • Relationship to its basal-endfoot local-translation role not integrated
10. 2025 Low

    Implicated ARHGAP11A upstream of FAM83A/LDHA in lung adenocarcinoma glycolysis and proliferation, extending its oncogenic reach to metabolic reprogramming.

    Evidence siRNA knockdown, Western blot, CCK-8, flow cytometry, glycolysis assays

    PMID:41674985

    Open questions at the time

    • No direct binding or mechanistic link to FAM83A shown
    • Single knockdown approach; not reconstituted

• How ARHGAP11A's GAP-dependent and GAP-independent activities, its spatially localized translation, and its degradative control are integrated into a unified regulatory logic across neurogenesis, mitosis, and cancer remains unresolved.
• No structural model of the GAP domain or its effector interfaces in the corpus
• Determinants selecting RhoA inactivation versus Rac1B/TPM1 binding unknown
• Integration of basal local translation with apical RHOA-ROCK control not established