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.   


    AuthorTitleJournalYearArticle Link
    Zhang, Jiahui et al.Phillygenin prevents osteoclast differentiation and bone loss by targeting RhoAPhytotherapy Research2024ISSN 1099--1573
    Bock, Fabian et al.Rac1 promotes kidney collecting duct repair by mechanically coupling cell morphology to mitotic entryScience advances2024ISSN 2375-2548
    Moztarzadeh, Sina et al.Cortactin is in a complex with VE-cadherin and is required for endothelial adherens junction stability through Rap1/Rac1 activationScientific Reports 2024 14:12024ISSN 2045--2322
    González, Yasmilde Rodríguez et al.PFTK1 kinase regulates axogenesis during development via RhoA activationBMC Biology2023ISSN 1741-7007
    Ye, Qian et al.Deficiency of gluconeogenic enzyme PCK1 promotes metabolic-associated fatty liver disease through PI3K/AKT/PDGF axis activation in male miceNature Communications 2023 14:12023ISSN 2041--1723
    Werder, Rhiannon B. et al.The COPD GWAS gene ADGRG6 instructs function and injury response in human iPSC-derived type II alveolar epithelial cellsAmerican journal of human genetics2023ISSN 1537--6605
    Toffali, Lara et al.An isoform of the giant protein titin is a master regulator of human T lymphocyte traffickingCell reports2023ISSN 2211--1247
    Bartos, Katalin et al.Renal FGF23 signaling depends on redox protein Memo1 and promotes orthovanadate-sensitive protein phosphotyrosyl phosphatase activityJournal of Cell Communication and Signaling2023ISSN 1873-961X
    Escuin, Sarah et al.Dual mechanism underlying failure of neural tube closure in the Zic2 mutant mouseDMM Disease Models and Mechanisms2023ISSN 1754-8411
    Dang, Iren et al.Key role for Rac in the early transcriptional response to extracellular matrix stiffness and stiffness-dependent repression of ATF3Journal of Cell Science2023ISSN 1477-9137
    Martínez-Rendón, Jacqueline et al.Ouabain Induces Transcript Changes and Activation of RhoA/ROCK Signaling in Cultured Epithelial Cells (MDCK)Current Issues in Molecular Biology2023ISSN 1467-3045
    Rogg, Manuel et al.A YAP/TAZ–ARHGAP29–RhoA Signaling Axis Regulates Podocyte Protrusions and Integrin AdhesionsCells2023ISSN 2073-4409
    Choi, Hyehun et al.LRRC8A anion channels modulate vascular reactivity via association with Myosin Phosphatase Rho Interacting Protein (MPRIP)FASEB journal : official publication of the Federation of American Societies for Experimental Biology2023ISSN 1530-6860
    Lopes-Rodrigues, Vanessa et al.AraC interacts with p75NTR transmembrane domain to induce cell death of mature neuronsCell Death & Disease 2023 14:72023ISSN 2041--4889
    Zhai, Ruoyang et al.Effects of sevof****** on lung epithelial permeability in experimental models of acute respiratory distress syndromeJournal of Translational Medicine2023ISSN 1479-5876
    Crespo, Grace Velez et al.The Rac inhibitor HV-107 as a potential therapeutic for metastatic breast cancerMolecular Medicine2023ISSN 1528-3658
    Morishita, Jun et al.Identification of a small RhoA GTPase inhibitor effective in fission yeast and human cellsOpen Biology2023ISSN 2046-2441
    Anastasaki, Corina et al.Generation of human induced pluripotent stem cell-derived cerebral organoids for cellular and molecular characterizationSTAR Protocols2022ISSN 2666--1667
    Zanin, Juan P. et al.p75NTR prevents the onset of cerebellar granule cell migration via RhoA activationeLife2022ISSN 2050-084X
    Sánchez-de la Torre, Aníbal et al.Cannabinoid CB1 receptor gene inactivation in oligodendrocyte precursors disrupts oligodendrogenesis and myelination in miceCell Death & Disease 2022 13:72022ISSN 2041--4889
    Weder, Bruce et al.New Therapeutic Approach for Intestinal Fibrosis Through Inhibition of pH-Sensing Receptor GPR4Inflammatory Bowel Diseases2022ISSN 1078--0998
    Yadav, Vikas et al.Increased MARCKS Activity in BRAF Inhibitor-Resistant Melanoma Cells Is Essential for Their Enhanced Metastatic Behavior Independent of Elevated WNT5A and IL-6 SignalingCancers2022ISSN 2072-6694
    Kumar, Akhilesh et al.Essential role of Rnd1 in innate immunity during viral and bacterial infectionsCell Death & Disease 2022 13:62022ISSN 2041--4889
    Wang, Kankai et al.PTBP1 knockdown promotes neural differentiation of glioblastoma cells through UNC5B receptorTheranostics2022ISSN 1838-7640
    de Vallière, Cheryl et al.pH-Sensing G Protein-Coupled Receptor OGR1 (GPR68) Expression and Activation Increases in Intestinal Inflammation and FibrosisInternational Journal of Molecular Sciences2022ISSN 1422-0067
    Meng, Zhipeng et al.The Hippo pathway mediates Semaphorin signalingScience Advances2022ISSN 2375-2548
    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
    Hasan, Wan Nuraini Wan et al.Annatto-derived tocotrienol promotes mineralization of MC3T3-E1 cells by enhancing BMP-2 protein expression via inhibiting RhoA activation and HMG-CoA reductase gene expressionDrug Design, Development and Therapy2020ISSN 1177-8881
    Rong, Zhouyi et al.Activation of FAK/Rac1/Cdc42-GTPase signaling ameliorates impaired microglial migration response to Aβ42 in triggering receptor expressed on myeloid cells 2 loss-of-function murine modelsFASEB Journal2020ISSN 1530-6860
    Lachowski, Dariusz et al.G Protein-Coupled Estrogen Receptor Regulates Actin Cytoskeleton Dynamics to Impair Cell PolarizationFrontiers in Cell and Developmental Biology2020ISSN 2296-634X
    Salgado-Lucio, Monica L. et al.FAK regulates actin polymerization during sperm capacitation via the ERK2/GEF-H1/RhoA signaling pathwayJournal of Cell Science2020ISSN 1477-9137
    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
    Rom, Slava et al.The dual action of poly(ADP-ribose) polymerase -1 (PARP-1) inhibition in HIV-1 infection: HIV-1 ltr inhibition and diminution in Rho GTPase activityFrontiers in Microbiology2015ISSN 1664-302X
    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
    Papke, Christina L. et al.Smooth muscle hyperplasia due to loss of smooth muscle α-actin is driven by activation of focal adhesion kinase, altered p53 localization and increased levels of platelet-derived growth factor receptor-βHuman Molecular Genetics2013ISSN 0964-6906
    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
    Chen, Guang et al.Inhibition of chemokine (CXC motif) ligand 12/chemokine (CXC motif) receptor 4 axis (CXCL12/CXCR4)-mediated cell migration by targeting mammalian target of rapamycin (mTOR) pathway in human gastric carcinoma cells (Journal of Biological Chemistry (2012) 2Journal of Biological Chemistry2012ISSN 0021-9258
    Greco, Carolina M. et al.Chemotactic effect of prorenin on human aortic smooth muscle cells: a novel function of the (pro)renin receptorCardiovascular Research2012ISSN 0008--6363
    Dhaliwal, Anandika et al.Cellular Cytoskeleton Dynamics Modulates Non-Viral Gene Delivery through RhoGTPases2012PMID 22509380
    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
    Chen, Si Meng et al.Inhibition of tumor cell growth, proliferation and migration by X-387, a novel active-site inhibitor of mTORBiochemical Pharmacology2012ISSN 0006-2952
    Howe, Grant A. et al.RhoB controls endothelial cell morphogenesis in part via negative regulation of RhoAVascular Cell2012ISSN 2045--824X
    Yang, Seungwon et al.The RhoA-ROCK-PTEN pathway as a molecular switch for anchorage dependent cell behaviorBiomaterials2012ISSN 1878--5905
    Garrido‐Gómez, Tamara et al.Annexin A2 is critical for embryo adhesiveness to the human endometrium by RhoA activation through F‐actin regulationThe FASEB Journal2012ISSN 0892--6638
    Zhou, Zhigang et al.HSV-mediated gene transfer of C3 transferase inhibits Rho to promote axonal regenerationExperimental Neurology2012ISSN 0014--4886
    McCoy, Kelly L. et al.Protease-activated receptor 1 (PAR1) coupling to G(q/11) but not to G(i/o) or G(12/13) is mediated by discrete amino acids within the receptor second intracellular loopCellular signalling2012ISSN 1873--3913
    Ramseyer, Vanesa D. et al.Tumor necrosis factor α decreases nitric oxide synthase type 3 expression primarily via Rho/Rho kinase in the thick ascending limbHypertension (Dallas, Tex. : 1979)2012ISSN 1524--4563
    Takefuji, Mikito et al.G13-mediated signaling pathway is required for pressure overload-induced cardiac remodeling and heart failureCirculation2012ISSN 0009-7322
    Jin, Wanzhu et al.Increased SRF transcriptional activity in human and mouse skeletal muscle is a signature of insulin resistanceJournal of Clinical Investigation2011ISSN 0021-9738
    Aguilar, Hector N. et al.Phos-tag-based analysis of myosin regulatory light chain phosphorylation in human uterine myocytesPLoS ONE2011ISSN 1932-6203
    Ganguly, Riya et al.Adiponectin Increases LPL Activity via RhoA/ROCK-Mediated Actin Remodelling in Adult Rat CardiomyocytesEndocrinology2011ISSN 0013--7227
    Musso, Alessandra et al.Relevance of the mevalonate biosynthetic pathway in the regulation of bone marrow mesenchymal stromal cell-mediated effects on T-cell proliferation and B-cell survivalHaematologica2011ISSN 1592--8721
    Lichtenstein, Mathieu P. et al.Secretase-independent and RhoGTPase/PAK/ERK-dependent regulation of cytoskeleton dynamics in astrocytes by NSAIDs and derivativesJournal of Alzheimer's disease : JAD2010ISSN 1875--8908
    Ridgway, Lon D. et al.Modulation of GEF-H1 Induced Signaling by Heparanase in Brain Metastatic Melanoma CellsJournal of cellular biochemistry2010ISSN 0730-2312
    Rapier, Rebecca et al.The extracellular matrix microtopography drives critical changes in cellular motility and Rho A activity in colon cancer cellsCancer Cell International2010ISSN 1475-2867
    Romero, Ana M. et al.Chronic ethanol exposure alters the levels, assembly, and cellular organization of the actin cytoskeleton and microtubules in hippocampal neurons in primary cultureToxicological Sciences2010ISSN 1096-6080
    Nini, Lylia et al.Accurate and reproducible measurements of RhoA activation in small samples of primary cellsAnalytical biochemistry2010ISSN 1096--0309
    Yang, Enyue et al.Fluoride induces vascular contraction through activation of RhoA/Rho kinase pathway in isolated rat aortasEnvironmental toxicology and pharmacology2010ISSN 1872--7077
    Hammar, Eva et al.Role of the Rho-ROCK (Rho-Associated Kinase) Signaling Pathway in the Regulation of Pancreatic β-Cell FunctionEndocrinology2009ISSN 0013--7227
    Chastre, Eric et al.TRIP6, a novel molecular partner of the MAGI-1 scaffolding molecule, promotes invasivenessThe FASEB Journal2009ISSN 1530--6860
    Seifert, Jennifer L. et al.Differential activation of Rac1 and RhoA in neuroblastoma cell fractionsNeuroscience letters2009ISSN 0304--3940
    Ramirez, Servio H. et al.Activation of Peroxisome Proliferator-Activated Receptor γ (PPARγ) Suppresses Rho GTPases in Human Brain Microvascular Endothelial Cells and Inhibits Adhesion and Transendothelial Migration of HIV-1 Infected MonocytesThe Journal of Immunology2008ISSN 0022--1767
    Kinoshita, Nagatoki et al.Apical Accumulation of Rho in the Neural Plate Is Important for Neural Plate Cell Shape Change and Neural Tube FormationMolecular Biology of the Cell2008ISSN 1059-1524
    Mercer, Jason et al.Vaccinia virus uses macropinocytosis and apoptotic mimicry to enter host cellsScience (New York, N.Y.)2008ISSN 1095--9203
    Sequeira, Linda et al.Rho GTPases in PC-3 prostate cancer cell morphology, invasion and tumor cell diapedesisClinical & experimental metastasis2008ISSN 0262--0898
    Moore, Simon W. et al.Rho inhibition recruits DCC to the neuronal plasma membrane and enhances axon chemoattraction to netrin 1Development2008ISSN 0950--1991
    Korobova, Farida et al.Arp2/3 complex is important for filopodia formation, growth cone motility, and neuritogenesis in neuronal cellsMolecular biology of the cell2008ISSN 1939--4586
    Tanaka, Shigeru et al.Neural expression of G protein-coupled receptors GPR3, GPR6, and GPR12 up-regulates cyclic AMP levels and promotes neurite outgrowthThe Journal of biological chemistry2007ISSN 0021--9258
    Schreibelt, Gerty et al.Reactive oxygen species alter brain endothelial tight junction dynamics via RhoA, PI3 kinase, and PKB signalingFASEB journal : official publication of the Federation of American Societies for Experimental Biology2007ISSN 1530--6860
    Keely, Patricia J. et al.Investigating integrin regulation and signaling events in three-dimensional systemsMethods in enzymology2007ISSN 0076--6879
    Rupp, Paul A. et al.A role for RhoA in the two-phase migratory pattern of post-otic neural crest cellsDevelopmental Biology2007ISSN 0012-1606
    Bradley, William D. et al.Integrin Signaling through Arg Activates p190RhoGAP by Promoting Its Binding to p120RasGAP and Recruitment to the MembraneMolecular Biology of the Cell2006ISSN 1059-1524

    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.