RhoA G-LISA Activation Assay Kit (Colorimetric format) 24 assays

G-LISA RhoA Activation Assay Biochem Kit (Colorimetric format)


Product Uses Include

  • Rho signaling pathway studies
  • Rho activation assays with primary cells
  • Rho activation assays with limited material
  • High throughput screens for Rho activation

The G-LISA Rho activation assays are ELISA based Rho activation assays with which you can measure Rho activity in cells in less than 3 h. BK124 is very sensitive and has excellent accuracy between duplicate samples. For a more detailed introduction on G-LISA assays and a listing of other available G-LISA kits, see our main G-LISA page. The BK124 Rho activation assay kit measures the level of GTP-loaded RhoA only in cells. The level of activation is measured with absorbance set at 490nm. For a kit to measure RhoA activation with luminescence detection, see Cat. # BK121.

See G-LISA FAQs tab on our G-LISA page for more details.

Know Your Rho Package

Kit contents
The kit contains sufficient reagents to perform 24 RhoA activation assays. Since the Rho-GTP affinity wells are supplied as strips and the strips can be broken into smaller pieces, each kit can be used for anywhere from one to multiple assays. The following components are included in the kit:

  1. Rho-GTP affinity wells (3 strips of 8 wells)
  2. Lysis buffer
  3. Binding buffer
  4. Antigen presenting buffer
  5. Wash buffer
  6. Antibody dilution buffer
  7. Anti-RhoA antibody
  8. HRP-labeled secondary antibody
  9. Positive control RhoA protein
  10. Protease inhibitor cocktail (Cat. # PIC02)
  11. Absorbance detection reagents
  12. Precision Red™ Advanced protein assay reagent (Cat. # ADV02)
  13. Manual with detailed protocols and extensive troubleshooting guide


Equipment needed

  1. 96-well plate spectrophotometer capable of reading 490 nm wavelength
  2. Multichannel or multidispensing pipettor
  3. Orbital microplate shaker capable of at least 200 rpm shaking (400 rpm is optimal)

Example results
Serum starved Swiss 3T3 cells were stimulated with the Rho activating compound calpeptin and RhoA activation was measured with the G-LISA method (Figures 1 and 2)


Figure 1. RhoA activation by calpeptin measured by G-LISA kit BK124. Swiss 3T3 (mouse) cells were serum starved for 24 h and treated with calpeptin (Cal; 0.1 mg/ml for 30 min) or DMSO carrier only (SS). 10 µg of cell lysates were subjected to the G-LISA™ assay. Absorbance was read at 490 nm.


Figure 2. Rho activity measured in Swiss 3T3 cells treated with the Cell Permeable Rho Inhibitor (CT04) using the RhoA G-LISA Activation Assay (Cat.# BK124). Serum starved Swiss 3T3 fibroblasts were untreated (no CT04) or treated with 0.20, 0.50 and 2.0 µg/ml of CT04 for 4h in serum free medium at 37°C, then activated with 100µg/ml calpeptin for 10min.  Cells were then lysed and RhoA activity was measured by the RhoA G-LISA Activation Assay (Cat.# BK124).  Note: At 2.0 µg/ml CT04 for 4h results in almost complete (90%) inhibition of RhoA activity.

Go to main G-LISA page


Associated Products:

Total RhoA ELISA (Cat. # BK150)

Anti-RhoA monoclonal antibody (Cat.# ARH03)

Rho Inhibitor I (Cat.# CT04)

Rho Activator II (Cat.# CN03)

Rho Pathway Inhibitor I - Rho Kinase (ROCK) inhibitor Y-27632 (Cat. # CN06)

For product Datasheets and MSDSs please click on the PDF links below.   


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    Wang, Kankai et al.PTBP1 knockdown promotes neural differentiation of glioblastoma cells through UNC5B receptorTheranostics2022ISSN 1838-7640
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    Darp, Revati et al.Oncogenic BRAF induces whole-genome doubling through suppression of cytokinesisNature Communications 2022 13:12022ISSN 2041--1723
    Vadakumchery, Anila et al.The Small GTPase RHOA Links SLP65 Activation to PTEN Function in Pre B Cells and Is Essential for the Generation and Survival of Normal and Malignant B CellsFrontiers in Immunology2022ISSN 1664-3224
    Hauke, Michael et al.Active RhoA Exerts an Inhibitory Effect on the Homeostasis and Angiogenic Capacity of Human Endothelial CellsJournal of the American Heart Association2022ISSN 2047-9980
    Xue, Tan et al.Effects of Aster B-mediated intracellular accumulation of cholesterol on inflammatory process and myocardial cells in acute myocardial infarctionHellenic Journal of Cardiology2022
    Francis, Caitlin R. et al.Rab35 governs apicobasal polarity through regulation of actin dynamics during sprouting angiogenesisNature Communications 2022 13:12022ISSN 2041--1723
    Kumar, Akhilesh et al.Essential role of Rnd1 in innate immunity during viral and bacterial infectionsCell Death & Disease2022Article Link
    Ma, Yuanyuan et al.Ror2-mediated non-canonical Wnt signaling regulates Cdc42 and cell proliferation during tooth root developmentDevelopment (Cambridge)2021ISSN 1477-9129
    Jozic, Ivan et al.Glucocorticoid-mediated induction of caveolin-1 disrupts cytoskeletal organization, inhibits cell migration and re-epithelialization of non-healing woundsCommunications Biology2021ISSN 2399-3642
    Gurusamy, Malarvizhi et al.G-protein-coupled receptor P2Y10 facilitates chemokine-induced CD4 T cell migration through autocrine/paracrine mediatorsNature Communications2021ISSN 2041-1723
    Zhou, Qun et al.Inflammatory Immune Cytokine TNF-α Modulates Ezrin Protein Activation via FAK/RhoA Signaling Pathway in PMVECs HyperpermeabilityFrontiers in Pharmacology2021ISSN 1663-9812
    Porter, Lauren et al.SUN1/2 Are Essential for RhoA/ROCK-Regulated Actomyosin Activity in Isolated Vascular Smooth Muscle CellsCells2020ISSN 2073-4409
    Krueger, Irena et al.Reelin amplifies glycoprotein VI activation and alphaiib beta3 integrin outside-in signaling via PLC Gamma 2 and Rho GTPasesArteriosclerosis, Thrombosis, and Vascular Biology2020ISSN 1524-4636
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    Lachowski, Dariusz et al.G Protein-Coupled Estrogen Receptor Regulates Actin Cytoskeleton Dynamics to Impair Cell PolarizationFrontiers in Cell and Developmental Biology2020ISSN 2296-634X
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    Dias Gomes, Martim et al.Polarity signaling ensures epidermal homeostasis by coupling cellular mechanics and genomic integrityNature Communications2019ISSN 2041-1723
    Majolée, Jisca et al.CSN5 inhibition triggers inflammatory signaling and Rho/ROCK-dependent loss of endothelial integrityScientific Reports2019ISSN 2045-2322
    Santhana Kumar, Karthiga et al.TGF-β Determines the Pro-migratory Potential of bFGF Signaling in MedulloblastomaCell Reports2018ISSN 2211-1247
    Li, Xu et al.A positive feedback loop of profilin-1 and RhoA/ROCK1 promotes endothelial dysfunction and oxidative stressOxidative Medicine and Cellular Longevity2018ISSN 1942-0994
    Patra, Vijay Kumar et al.The Skin Microbiome: Is It Affected by UV-induced Immune Suppression?Frontiers in Microbiology2016ISSN 1664-302X
    Lu, Wen Juan et al.Senescence Mediated by p16INK4a Impedes Reprogramming of Human Corneal Endothelial Cells into Neural Crest ProgenitorsScientific Reports2016ISSN 2045-2322
    Yu, Yonghao et al.Hydrogen-rich medium ameliorates lipopolysaccharide-induced barrier dysfunction via rhoa-mdia1 signaling in caco-2 cellsShock2016ISSN 1540-0514
    López-Posadas, Rocío et al.Rho-A prenylation and signaling link epithelial homeostasis to intestinal inflammationJournal of Clinical Investigation2016ISSN 1558-8238
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    Tang, Xiao et al.HCLOCK Causes Rho-Kinase-Mediated Endothelial Dysfunction and NF-κ B-Mediated Inflammatory ResponsesOxidative Medicine and Cellular Longevity2015ISSN 1942-0994
    Manukyan, Arkadi et al.A complex of p190RhoGAP-A and anillin modulates RhoA-GTP and the cytokinetic furrow in human cellsJournal of Cell Science2015ISSN 1477-9137
    Rom, Slava et al.Poly(ADP-ribose) polymerase-1 inhibition in brain endothelium protects the blood-brain barrier under physiologic and neuroinflammatory conditionsJournal of Cerebral Blood Flow and Metabolism2015ISSN 1559-7016
    Herr, Michael J. et al.Tetraspanin CD9 regulates cell contraction and actin arrangement via RhoA in human vascular smooth muscle cellsPLoS ONE2014ISSN 1932-6203
    Biechler V., Stefanie V. et al.The impact of flow-induced forces on the morphogenesis of the outflow tractFrontiers in Physiology2014ISSN 1664-042X
    Mackay, Joanna L. et al.Simultaneous and independent tuning of RhoA and Rac1 activity with orthogonally inducible promotersIntegrative Biology (United Kingdom)2014ISSN 1757-9708
    Chen, Xiaofei et al.The TMEFF2 tumor suppressor modulates integrin expression, RhoA activation and migration of prostate cancer cellsBiochimica et Biophysica Acta - Molecular Cell Research2014ISSN 1879-2596
    Zhu, Ying Ting et al.Knockdown of both p120 catenin and kaiso promotes expansion of human corneal endothelial monolayers via rhoa-rock-noncanonical BMP-NFκB pathwayInvestigative Ophthalmology and Visual Science2014ISSN 1552-5783
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    Tan, Hong et al.Fluid flow forces and rhoA regulate fibrous development of the atrioventricular valvesDevelopmental Biology2013ISSN 1095-564X
    Kalia, Manjula et al.Japanese Encephalitis Virus Infects Neuronal Cells through a Clathrin-Independent Endocytic MechanismJournal of Virology2013ISSN 0022--538X
    Kanazawa, Yasushi et al.The Rho-kinase inhibitor fasudil restores normal motor nerve conduction velocity in diabetic rats by assuring the proper localization of adhesion-related molecules in myelinating Schwann cellsExperimental neurology2013ISSN 1090--2430
    DiScipio, Richard G. et al.Complement C3a signaling mediates production of angiogenic factors in mesenchymal stem cellsJournal of Biomedical Science and Engineering2013ISSN 1937--6871
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    Ramsay, Alan G. et al.Multiple inhibitory ligands induce impaired T-cell immunologic synapse function in chronic lymphocytic leukemia that can be blocked with lenali******: Establishing a reversible immune evasion mechanism in human cancerBlood2012ISSN 1528-0020
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    Question 1:  Can I detect isoforms other than RhoA, Rac1 or RalA with these G-LISA activation assays?

    Answer 1:  Yes, the RhoA G-LISA (Cat. # BK124), Rac1 G-LISA (Cat. # BK128) and RalA G-LISA (Cat. # BK129) can be used to detect RhoB or RhoC, Rac 2 or Rac3 or RalB, respectively.  The capture proteins that the wells have been coated with bind all of the isoforms of the respective GTPase.  The specificity of signal is conferred by the specificity of the monoclonal primary antibody utilized.  Use of an isoform-specific monoclonal antibody allows detection of other Rho family isoforms.  Please see this citation for an example of this modified procedure (Hall et al., 2008. Type I Collagen Receptor (α2β1) Signaling Promotes Prostate Cancer Invasion through RhoC GTPase. Neoplasia. 10, 797–803). 

    Basically the researcher would test their specific monoclonal antibody in a western blot first to prove specificity to the alternative isoform of interest.  For example, load RhoA and C for negative controls when testing a RhoB monoclonal antibody.  Then the researcher would use 1:50, 1:200 and 1:500 dilutions of their monoclonal antibody on duplicate cell extracts of activated and control state samples. The researcher would then choose the dilution of monoclonal antibody which gave them the highest ratio of activated:control state.

    A simple activated/control state pair of extracts can be made by growing cells to 50% confluence in serum containing media, washing twice with PBS, preparing lysate and aliquoting and freezing  samples in liquid nitrogen.  With one aliquot, defrost and let stand at room temperature for 60 min to degrade the activated signal to a low basal signal, which will be the control state.  The untreated sample (2nd aliquot) will be considered “activated” which most serum grown cells are.


    Question 2:  How many cell culture plates can I process at one time during the lysis step?

    Answer 2:  We recommend that from the point at you add lysis buffer to the plate on ice to aliquoting and snap-freezing the lysate samples in liquid nitrogen, no more than 10 min are allowed to elapse.  After 10 min on ice, we find that GTP bound to GTPases (activated GTPases) undergoes rapid hydrolysis.  Rapid processing at 4°C is essential for accurate and reproducible results.  The following guidelines are useful for rapid lysis of cells.


    a.  Retrieve culture dish from incubator, immediately aspirate out all of the media and place firmly on ice.

    b.  Immediately rinse cells with an appropriate volume of ice cold PBS (for Cdc42 activation, skip this step and simply aspirate the media) to remove serum proteins.

    c.  Aspirate off all residual PBS buffer. This is essential so that the Lysis Buffer is not diluted. Correct aspiration requires that the culture dish is placed at a steep angle on ice for 1 min to allow excess PBS to collect in the vessel for complete removal.  As noted, the time period between cell lysis and addition of lysates to the wells is critically important. Take the following precautions:

         1.  Work quickly.

         2.  Keeping solutions and lysates embedded in ice so that the temperature is below 4°C. This helps to minimize changes in signal over time.

         3.  We strongly recommend that cell lysates be immediately frozen after harvest and clarification. A sample of at least 20 μl should be kept on ice for protein concentration measurement. The lysates must be snap frozen in liquid nitrogen and stored at -70°C. Lysates should be stored at -70°C for no longer than 30 days.

         4.  Thawing of cell lysates prior to use in the G-LISA assay should be in a room temperature water bath, followed by rapid transfer to ice and immediate use in the assay.


    If you have any questions concerning this product, please contact our Technical Service department at tservice@cytoskeleton.com.