Name: rab10 phosphorylation detection by lrrk2 activity using sds-page with a phosphate-binding tag
Uploaded: 2017-12-14T14:00:00.000+00:00
Duration: 8 min 55 s
Description: Watch this Scientific Journal Video about Rab10 Phosphorylation Detection by LRRK2 Activity Using SDS-PAGE with a Phosphate-binding Tag at JoVE.com

Agradecemos a Dr. Takeshi Iwatsubo (Universidad de Tokio, Japón) por proporcionar amablemente la plásmidos codifican 3xFLAG LRRK2 WT y mutantes. También agradecemos a Dr. Dario Alessi (Universidad de Dundee, Reino Unido) por proporcionar amablemente MLi-2 y el plásmido codificación HA-Rab10. Este trabajo fue apoyado por la sociedad japonesa para la promoción de la ciencia (JSPS) KAKENHI concesión número JP17K08265 (G.I.).

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Aquí, describimos un método robusto y fácil de detectar Rab10 fosforilación de LRRK2 nivel endógeno basado en la metodología de la etiqueta P. Porque el anticuerpo actualmente disponible contra Rab10 fosforilada sólo funciona con las proteínas sobreexpresadas15, el presente método utiliza la etiqueta P SDS-PAGE es la única manera de evaluar los niveles endógenos de la fosforilación Rab10. Por otra parte, el presente método permite la estimación de la estequiometría de la fosforilaci...

PD es una de las enfermedades neurodegenerativas más comunes, que afecta predominante a las neuronas dopaminérgicas en el cerebro medio, dando por resultado la disfunción de los sistemas de motor en personas de edad avanzada1. Mientras que la mayoría de los pacientes desarrollará PD de manera esporádica, hay familias que heredar la enfermedad. Se han encontrado mutaciones en varios genes vinculados con FPD2. Uno de los genes causales de la FPD es LRRK2, en el que ocho mutaciones sin sentido (N1437H, R1441C/G/H/S, Y1699C, G2019S y I2020T) vinculadas a un dominante heredado FPD llamada PARK8 hasta ahora han sido reportados3,4,5. Varios estudios de Asociación de genoma completo (GWAS) de pacientes con EP esporádicos también han identificado variaciones genómicas en el locus del LRRK2 como factor de riesgo para PD, lo que sugiere que la anormalidad en la función de LRRK2 es una causa común de la neurodegeneración en los esporádicos y PARK8 FPD6,7,8.
LRRK2 es una proteína grande (2.527 aminoácidos) que consiste en un dominio repetición rica en leucina, un Ras de unión a GTP dominio de proteínas complejas (ROC), un C-terminal de dominio, un dominio de la cinasa de serina/treonina proteína y WD40 dominio repetición9ROC (CDR). Las ocho mutaciones FPD localizar en estos dominios funcionales; N1437H y R1441C/G/H/S en el dominio ROC, Y1699C en el dominio de la COR, G2019S y I2020T en el dominio de la cinasa. Puesto que la mutación G2019S, que es lo más frecuentemente encontrado mutación en PD pacientes10,11,12, aumenta la actividad de la quinasa de LRRK2 en 2-3 veces en vitro13, se presume que el aumento anormal de fosforilación de los substratos de LRRK2 es tóxico para las neuronas. Sin embargo, ha sido imposible estudiar si se altera la fosforilación de sustratos fisiológicamente relevantes de LRRK2 en pacientes con EP familiar/esporádico debido a la falta de métodos de evaluación en muestras derivadas.
Fosforilación de la proteína es generalmente detectada por immunoblotting o análisis enzima-ligado del inmunosorbente (ELISA) usando los anticuerpos específicamente reconociendo el estado fosforilado de proteínas o por análisis de espectrometría de masa. Sin embargo, la estrategia anterior a veces no se puede aplicar debido a las dificultades en la creación de anticuerpos específicos de fosforilación. Etiquetado metabólico de las células con fosfato radiactivo es otra opción para examinar niveles fisiológicos de la fosforilación de cuando los anticuerpos específicos de fosforilación no están disponibles. Sin embargo, requiere una gran cantidad de materiales radiactivos y por lo tanto implica algunos equipos especializados para protección radiológica14. El análisis de espectrometría de masa es más sensible frente a estos métodos inmunoquímicos y llegó a ser popular en el análisis de la fosforilación de la proteína. Sin embargo, la preparación de la muestra es desperdiciador de tiempo y costosos instrumentos son necesarios para el análisis.
Un subconjunto de la familia de Rab GTPase como Rab10 y Rab8 fue divulgado recientemente como sustratos fisiológicos directos para LRRK2 basan en el resultado de un análisis a gran escala phosphoproteomic del15. Entonces hemos demostrado que la fosforilación Rab10 fue aumentada por mutaciones de la FPD en fibroblastos embrionarios de ratón y en los pulmones de knockin ratones16. En este informe, optamos por emplear una electroforesis en gel de poliacrilamida sodio dodecil sulfato (SDS-PAGE)-método en el cual una molécula de P-tag es co polimerizada en geles de SDS-PAGE (etiqueta P SDS-PAGE) para la detección de los niveles endógenos de la fosforilación Rab10, basado en porque todavía le faltaba un anticuerpo altamente sensible específico para Rab10 fosforilada. Nosotros hemos podido detectar la fosforilación de Rab8 endógeno debido a la pobre selectividad de anticuerpos disponibles para Rab8 total. Por lo tanto, decidimos enfocarnos en la fosforilación Rab10. LRRK2 fosforila Rab10 en Thr73 ubicación en el centro de la región altamente conservada "interruptor II". Conservación de los sitios de fosforilación entre proteínas Rab podría ser una de las razones por qué anticuerpos phosphospecific reconociendo distintas proteínas Rab son difíciles de hacer.
La fosforilación de Rab8A por LRRK2 inhibe la Unión de Rabin8, un factor de intercambio del nucleótido guanina (GEF) que activa Rab8A intercambiando el PIB consolidado con GTP15. Fosforilación de Rab10 y Rab8A por LRRK2 también inhibe la Unión de los inhibidores de la disociación de PIB (GDIs), que son esenciales para la activación de las proteínas Rab extrayendo proteínas Rab PIB-limite de membranas15. Colectivamente, se presume que la fosforilación de proteínas Rab por LRRK2 les impide la activación aunque el mecanismo molecular exacto y consecuencias fisiológicas de la fosforilación no quedan claros.
P-etiqueta SDS-PAGE fue inventado por Kinoshita et al. en 2006: en este método, acrilamida covalente fue juntada con la etiqueta P, una molécula captura de fosfatos con alta afinidad, que copolymerized en SDS-PAGE gel17. Porque las moléculas de P etiqueta en un gel de SDS-PAGE selectivamente retardan la movilidad electroforética de las proteínas fosforiladas, etiqueta P SDS-PAGE puede separar proteínas fosforiladas de los no-phosphorylated (figura 1). Si el proteína de interés es fosforilado en residuos múltiples, se observará una escalera de bandas correspondientes a las formas fosforiladas diferencialmente. En el caso de Rab10, observamos sólo una banda cambiada de puesto, lo que indica que Rab10 es fosforilado en Thr73. La gran ventaja de la etiqueta P SDS-PAGE en immunoblotting con anticuerpos específicos de fosforilación es que Rab10 fosforilada puede detectarse por immunoblotting con fosforilación-anticuerpos inespecíficos (es decir, reconocimiento total Rab10) Tras ser trasladado en las membranas, que suele ser más específicos, sensibles y disponibles de fuentes comerciales y académico. Otra ventaja de usar la etiqueta P SDS-PAGE es que se puede obtener una estimación aproximada de la estequiometría de la fosforilación, que es imposible por immunoblotting con anticuerpos específicos de fosforilación o por el etiquetado metabólico de las células con radiactivo fosfatos.
Aparte del uso de acrilamida etiqueta P barata y algunas modificaciones menores relacionados con ella, el método actual de detección de Rab10 fosforilación de LRRK2 sigue un protocolo general de immunoblotting.Por lo tanto, debe ser sencillo y fácilmente ejecutable en cualquier laboratorios donde immunoblotting es una práctica habitual, con cualquier tipo de muestras incluyendo proteínas purificadas, lysates de la célula y homogenados de tejido.

<table><tbody><tr><td>&lt;strong&gt;Reagents&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Dulbecco&#039;s phosphate-buffered saline (DPBS)</td><td>homemade</td><td></td><td>150 mM NaCl, 8 mM Na&lt;sub&gt;2&lt;/sub&gt;HPO&lt;sub&gt;4&lt;/sub&gt;-12H&lt;sub&gt;2&lt;/sub&gt;O, 2.7 mM KCl, 1.5 mM KH&lt;sub&gt;2&lt;/sub&gt;PO&lt;sub&gt;4 &lt;/sub&gt;in MilliQ water and sterilized by autoclaving</td></tr><tr><td>Sodium chloride</td><td>Nacalai Tesque</td><td>31320-34</td><td></td></tr><tr><td>Sodium Disodium Hydrogenphosphate 12-Water</td><td>Wako</td><td>196-02835</td><td></td></tr><tr><td>Potassium chloride</td><td>Wako</td><td>163-03545</td><td></td></tr><tr><td>Potassium Dihydrogen Phosphate</td><td>Wako</td><td>169-04245</td><td></td></tr><tr><td>2.5% Trypsin (10X)</td><td>Sigma-Aldrich</td><td>T4549</td><td>Dilute 10-fold with sterile DPBS for preparing working solution</td></tr><tr><td>Dulbecco&#039;s modified Eagle medium&lt;br/&gt; (DMEM)</td><td>Wako</td><td>044-29765</td><td></td></tr><tr><td>Fetal bovine serum</td><td>BioWest</td><td>S1560</td><td>Heat-inactivated at 56 &amp;deg;C for 30 min</td></tr><tr><td>Penicillin-Streptomycin (100X)</td><td>Wako</td><td>168-23191</td><td></td></tr><tr><td>HEPES</td><td>Wako</td><td>342-01375</td><td></td></tr><tr><td>Sodium hydroxide</td><td>Wako</td><td>198-13765</td><td></td></tr><tr><td>Polyethylenimine HCl MAX, Linear, Mw 40,000 (PEI MAX 40000)</td><td>PolySciences, Inc.</td><td>24765-1</td><td>Stock solution was prepared in 20 mM HEPES-NaOH pH 7.0 at 1 mg/mL and the pH was then adjusted to 7.0 with NaOH</td></tr><tr><td>Dimethyl sulfoxide</td><td>Wako</td><td>045-28335</td><td></td></tr><tr><td>Tris</td><td>STAR</td><td>RSP-THA500G</td><td></td></tr><tr><td>Hydrochloric acid</td><td>Wako</td><td>080-01066</td><td></td></tr><tr><td>Polyoxyethylene(10) Octylphenyl Ether</td><td>Wako</td><td>160-24751</td><td>Equivalent to Triton X-100</td></tr><tr><td>Ethylene glycol-bis(2-aminoethylether)-N,N,N&amp;rsquo;,N&amp;rsquo;-tetraacetic acid (EGTA)</td><td>Wako</td><td>346-01312</td><td></td></tr><tr><td>Sodium orthovanadate(V)</td><td>Wako</td><td>198-09752</td><td></td></tr><tr><td>Sodium fluoride</td><td>Kanto Chemical</td><td>37174-20</td><td></td></tr><tr><td>&amp;beta;-Glycerophosphoric Acid Disodium Salt Pentahydrate</td><td>Nacalai Tesque</td><td>17103-82</td><td></td></tr><tr><td>Sodium pyrophosphate decahydrate</td><td>Kokusan Chemical</td><td>2113899</td><td></td></tr><tr><td>Microcystin-LR</td><td>Wako</td><td>136-12241</td><td></td></tr><tr><td>Sucrose</td><td>Wako</td><td>196-00015</td><td></td></tr><tr><td>Complete EDTA-free protease inhibitor cocktail</td><td>Roche</td><td>11873580001</td><td>Dissolve one tablet in 1 mL water, which can be stored at -20 &amp;deg;C for a month. Use it at 1:50 dilution for cell lysis</td></tr><tr><td>Pierce Coomassie (Bradford) Protein Assay Kit</td><td>Thermo Fisher Scientific</td><td>23200</td><td></td></tr><tr><td>Sodium dodecyl sulfate</td><td>Nacalai Tesque</td><td>31607-65</td><td></td></tr><tr><td>Glycerol</td><td>Wako</td><td>075-00616</td><td></td></tr><tr><td>Bromophenol blue</td><td>Wako</td><td>021-02911</td><td></td></tr><tr><td>&amp;beta;-mercaptoethanol</td><td>Kanto Chemical</td><td>25099-00</td><td></td></tr><tr><td>Ethanol</td><td>Wako</td><td>056-06967</td><td></td></tr><tr><td>Methanol</td><td>Wako</td><td>136-01837</td><td></td></tr><tr><td>Phosphate-binding tag acrylamide</td><td>Wako</td><td>AAL-107</td><td>P-tag acrylamide</td></tr><tr><td>40% (w/v) acrylamide solution</td><td>Nacalai Tesque</td><td>06119-45</td><td>Acrylamide:Bis = 29:1</td></tr><tr><td>Tetramethylethylenediamine (TEMED)</td><td>Nacalai Tesque</td><td>33401-72</td><td></td></tr><tr><td>Ammonium persulfate (APS)</td><td>Wako</td><td>016-08021</td><td>10% (w/v) solution was prepared by dissolving the powder of ammonium persulfate in MilliQ water</td></tr><tr><td>2-propanol</td><td>Wako</td><td>166-04831</td><td></td></tr><tr><td>Manganese chloride tetrahydrate</td><td>Sigma-Aldrich</td><td>M3634</td><td></td></tr><tr><td>Precision Plus Protein Prestained Standard</td><td>Bio-Rad</td><td>1610374, 1610373, 1610377</td><td>Molecular weight marker used in the protocol</td></tr><tr><td>WIDE-VIEW Prestained Protein Size Marker III</td><td>Wako</td><td>230-02461</td><td></td></tr><tr><td>Glycine</td><td>Nacalai Tesque</td><td>17109-64</td><td></td></tr><tr><td>Amersham Protran NC 0.45</td><td>GE Healthcare</td><td>10600007</td><td>Nitrocellulose membrane</td></tr><tr><td>Durapore Membrane Filter</td><td>EMD Millipore</td><td>GVHP00010</td><td>PVDF membrane</td></tr><tr><td>Filter Papers No.1</td><td>Advantec</td><td>00013600</td><td></td></tr><tr><td>Ponceau S</td><td>Nacalai Tesque</td><td>28322-72</td><td></td></tr><tr><td>Acetic acid</td><td>Wako</td><td>017-00251</td><td></td></tr><tr><td>Tween-20</td><td>Sigma-Aldrich</td><td>P1379</td><td>polyoxyethylenesorbitan monolaurate</td></tr><tr><td>Ethylenediaminetetraacetic acid (EDTA)</td><td>Wako</td><td>345-01865</td><td></td></tr><tr><td>Skim milk powder</td><td>Difco Laboratories</td><td>232100</td><td></td></tr><tr><td>Immunostar</td><td>Wako</td><td>291-55203</td><td>ECL solution (Normal sensitivity)</td></tr><tr><td>Immunostar LD</td><td>Wako</td><td>290-69904</td><td>ECL solution (High sensitivity)</td></tr><tr><td>CBB staining solution</td><td>homemade</td><td></td><td>1 g CBB R-250, 50% (v/v) methanol, 10% (v/v) acetic acid in 1 L of MilliQ water</td></tr><tr><td>CBB R-250</td><td>Wako</td><td>031-17922</td><td></td></tr><tr><td>CBB destaining solution</td><td>homemade</td><td></td><td>12% (v/v) methanol, 7% (v/v) acetic acid in 1 L MilliQ water</td></tr><tr><td>&lt;strong&gt;Name&lt;/strong&gt;</td><td>&lt;strong&gt;Company&lt;/strong&gt;</td><td>&lt;strong&gt;Catalog Number&lt;/strong&gt;</td><td>&lt;strong&gt;Comments&lt;/strong&gt;</td></tr><tr><td>&lt;strong&gt;Antibodies&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>anti-HA antibody</td><td>Sigma-Aldrich</td><td>11583816001</td><td>Used at 0.2 &amp;mu;g/mL for immunoblotting.</td></tr><tr><td>anti-Rab10 antibody</td><td>Cell Signaling Technology</td><td>#8127</td><td>Used at 1:1000 for immunoblotting.&lt;br/&gt; Specificity was confirmed by CRISPR KO in Ito et al., Biochem J, 2016.</td></tr><tr><td>anti-pSer935 antibody</td><td>Abcam</td><td>ab133450</td><td>Used at 1 &amp;mu;g/mL for immunoblotting.</td></tr><tr><td>anti-LRRK2 antibody</td><td>Abcam</td><td>ab133518</td><td>Used at 1 &amp;mu;g/mL for immunoblotting.</td></tr><tr><td>anti-&amp;alpha;-tubulin antibody</td><td>Sigma-Aldrich</td><td>T9026</td><td>Used at 1 &amp;mu;g/mL for immunoblotting.</td></tr><tr><td>anti-GAPDH antibody</td><td>Santa-Cruz</td><td>sc-32233</td><td>Used at 0.02 &amp;mu;g/mL for immunoblotting.</td></tr><tr><td>Peroxidase AffiniPure Sheep Anti-Mouse IgG (H+L)</td><td>Jackson ImmunoResearch</td><td>515-035-003</td><td>Used at 0.16 &amp;mu;g/mL for immunoblotting.</td></tr><tr><td>Peroxidase AffiniPure Goat Anti-Rabbit IgG (H+L)</td><td>Jackson ImmunoResearch</td><td>111-035-003</td><td>Used at 0.16 &amp;mu;g/mL for immunoblotting.</td></tr><tr><td>&lt;strong&gt;Name&lt;/strong&gt;</td><td>&lt;strong&gt;Company&lt;/strong&gt;</td><td>&lt;strong&gt;Catalog Number&lt;/strong&gt;</td><td>&lt;strong&gt;Comments&lt;/strong&gt;</td></tr><tr><td>&lt;strong&gt;Inhibitors&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>GSK2578215A</td><td>MedChem Express</td><td>HY-13237</td><td>Stock solution was prepared in DMSO at 10 mM and stored at -80 &amp;deg;C</td></tr><tr><td>MLi-2</td><td>Provided by Dr Dario Alessi (University of Dundee)</td><td></td><td>Stock solution was prepared in DMSO at 10 mM and stored at -80 &amp;deg;C</td></tr><tr><td>&lt;strong&gt;Name&lt;/strong&gt;</td><td>&lt;strong&gt;Company&lt;/strong&gt;</td><td>&lt;strong&gt;Catalog Number&lt;/strong&gt;</td><td>&lt;strong&gt;Comments&lt;/strong&gt;</td></tr><tr><td>&lt;strong&gt;Plasmids&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Rab10/pcDNA5 FRT TO HA</td><td>Provided by Dr Dario Alessi&lt;br/&gt; (University of Dundee)</td><td></td><td>This plasmid expresses amino-terminally HA-tagged human Rab10.</td></tr><tr><td>LRRK2 WT/p3xFLAG-CMV-10</td><td>Provided by Dr Takeshi Iwatsubo (University of Tokyo)</td><td></td><td>Ito et al., Biochemistry, 46: 1380&amp;ndash;1388 (2007). This plasmid expresses amino-terminally 3xFLAG-tagged wild-type human LRRK2.</td></tr><tr><td>LRRK2 K1906M/p3xFLAG-CMV-10</td><td>Provided by Dr Takeshi Iwatsubo (University of Tokyo)</td><td></td><td>Ito et al., Biochemistry, 46: 1380&amp;ndash;1388 (2007). This plasmid expresses amino-terminally 3xFLAG-tagged K1906M kinase-inactive mutant of human LRRK2.</td></tr><tr><td>LRRK2 N1437H/p3xFLAG-CMV-10</td><td></td><td></td><td>This paper. This plasmid expresses amino-terminally 3xFLAG-tagged N1437H FPD mutant of human LRRK2.</td></tr><tr><td>LRRK2 R1441C/p3xFLAG-CMV-10</td><td>Provided by Dr Takeshi Iwatsubo (University of Tokyo)</td><td></td><td>Kamikawaji et al., Biochemistry, 48: 10963&amp;ndash;10975 (2013). This plasmid expresses amino-terminally 3xFLAG-tagged R1441C FPD mutant of human LRRK2.</td></tr><tr><td>LRRK2 R1441G/p3xFLAG-CMV-10</td><td>Provided by Dr Takeshi Iwatsubo (University of Tokyo)</td><td></td><td>Kamikawaji et al., Biochemistry, 48: 10963&amp;ndash;10975 (2013). This plasmid expresses amino-terminally 3xFLAG-tagged R1441G FPD mutant of human LRRK2.</td></tr><tr><td>LRRK2 R1441H/p3xFLAG-CMV-10</td><td>Provided by Dr Takeshi Iwatsubo (University of Tokyo)</td><td></td><td>Kamikawaji et al., Biochemistry, 48: 10963&amp;ndash;10975 (2013). This plasmid expresses amino-terminally 3xFLAG-tagged R1441H FPD mutant of human LRRK2.</td></tr><tr><td>LRRK2 R1441S/p3xFLAG-CMV-10</td><td></td><td></td><td>This paper. This plasmid expresses amino-terminally 3xFLAG-tagged R1441S FPD mutant of human LRRK2.</td></tr><tr><td>LRRK2 Y1699C/p3xFLAG-CMV-10</td><td>Provided by Dr Takeshi Iwatsubo (University of Tokyo)</td><td></td><td>Kamikawaji et al., Biochemistry, 48: 10963&amp;ndash;10975 (2013). This plasmid expresses amino-terminally 3xFLAG-tagged Y1699C FPD mutant of human LRRK2.</td></tr><tr><td>LRRK2 G2019S/p3xFLAG-CMV-10</td><td>Provided by Dr Takeshi Iwatsubo (University of Tokyo)</td><td></td><td>Kamikawaji et al., Biochemistry, 48: 10963&amp;ndash;10975 (2013). This plasmid expresses amino-terminally 3xFLAG-tagged G2019S FPD mutant of human LRRK2.</td></tr><tr><td>LRRK2 I2020T/p3xFLAG-CMV-10</td><td>Provided by Dr Takeshi Iwatsubo (University of Tokyo)</td><td></td><td>Kamikawaji et al., Biochemistry, 48: 10963&amp;ndash;10975 (2013). This plasmid expresses amino-terminally 3xFLAG-tagged I2020T FPD mutant of human LRRK2.</td></tr><tr><td>&lt;strong&gt;Name&lt;/strong&gt;</td><td>&lt;strong&gt;Company&lt;/strong&gt;</td><td>&lt;strong&gt;Catalog Number&lt;/strong&gt;</td><td>&lt;strong&gt;Comments&lt;/strong&gt;</td></tr><tr><td>&lt;strong&gt;Equipments&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>CO&lt;sub&gt;2&lt;/sub&gt; incubator</td><td>Thermo Fisher Scientific</td><td>Forma Series II 3110 Water-Jacketed</td><td></td></tr><tr><td>Auto Pipette</td><td>Drummond</td><td>Pipet-Aid PA-400</td><td></td></tr><tr><td>Micropipette P10</td><td>Nichiryo</td><td>00-NPX2-10</td><td>0.5&amp;ndash;10 &amp;mu;L</td></tr><tr><td>Micropipette P200</td><td>Nichiryo</td><td>00-NPX2-200</td><td>20&amp;ndash;200 &amp;mu;L</td></tr><tr><td>Micropipette P1000</td><td>Nichiryo</td><td>00-NPX2-1000</td><td>100&amp;ndash;1000 &amp;mu;L</td></tr><tr><td>Tips for micropipette P10</td><td>STAR</td><td>RST-481LCRST</td><td>Sterile</td></tr><tr><td>Tips for micropipette P200</td><td>FUKAEKASEI</td><td>1201-705YS</td><td>Sterile</td></tr><tr><td>Tips for micropipette P1000</td><td>STAR</td><td>RST-4810BRST</td><td>Sterile</td></tr><tr><td>5 mL disporsable pipette</td><td>Greiner</td><td>606180</td><td>Sterile</td></tr><tr><td>10 mL disporsable pipette</td><td>Greiner</td><td>607180</td><td>Sterile</td></tr><tr><td>25 mL disporsable pipette</td><td>Falcon</td><td>357535</td><td>Sterile</td></tr><tr><td>Hematocytometer</td><td>Sunlead Glass</td><td>A126</td><td>Improved Neubeuer</td></tr><tr><td>Microscope</td><td>Olympus</td><td>CKX53</td><td></td></tr><tr><td>10 cm dishes</td><td>Falcon</td><td>353003</td><td>For tissue culture</td></tr><tr><td>6-well plates</td><td>AGC Techno Glass</td><td>3810-006</td><td>For tissue culture</td></tr><tr><td>Vortex mixer</td><td>Scientific Industries</td><td>Vortex-Genie 2</td><td></td></tr><tr><td>Cell scrapers</td><td>Sumitomo Bakelite</td><td>MS-93100</td><td></td></tr><tr><td>1.5 mL tubes</td><td>STAR</td><td>RSV-MTT1.5</td><td></td></tr><tr><td>15 mL tubes</td><td>AGC Techno Glass</td><td>2323-015</td><td></td></tr><tr><td>50 mL tubes</td><td>AGC Techno Glass</td><td>2343-050</td><td></td></tr><tr><td>Centrifuges</td><td>TOMY</td><td>MX-307</td><td></td></tr><tr><td>96-well plates</td><td>Greiner</td><td>655061</td><td>Not for tissue culture</td></tr><tr><td>Plate reader</td><td>Molecular Devices</td><td>SpectraMax M2e</td><td></td></tr><tr><td>SDS&amp;ndash;PAGE tanks</td><td>Nihon Eido</td><td>NA-1010</td><td></td></tr><tr><td>Transfer tanks</td><td>Nihon Eido</td><td>NA-1510B</td><td></td></tr><tr><td>Gel plates (notched)</td><td>Nihon Eido</td><td>NA-1000-1</td><td></td></tr><tr><td>Gel plates (plain)</td><td>Nihon Eido</td><td>NA-1000-2</td><td></td></tr><tr><td>Silicon spacers</td><td>Nihon Eido</td><td>NA-1000-16</td><td></td></tr><tr><td>17-well combs</td><td>Nihon Eido</td><td>Custom made</td><td></td></tr><tr><td>Binder clips</td><td>Nihon Eido</td><td>NA-1000-15</td><td></td></tr><tr><td>5 mL syringe</td><td>Terumo</td><td>SS-05SZ</td><td></td></tr><tr><td>21G</td><td>Terumo</td><td>NN-2138R</td><td></td></tr><tr><td>Power Station 1000 VC</td><td>ATTO</td><td>AE-8450</td><td>Power supply for SDS&amp;ndash;PAGE and transfer</td></tr><tr><td>Large weighing boats</td><td>Ina Optika</td><td>AS-DL</td><td></td></tr><tr><td>Plastic containers</td><td>AS ONE</td><td>PS CASE No.4</td><td>10 x 80 x 50 mm</td></tr><tr><td>Rocking shaker</td><td>Titech</td><td>NR-10</td><td></td></tr><tr><td>Styrene foam box</td><td>generic</td><td></td><td>The internal dimensions should fit one transfer tank (200 x 250 x 250 mm).</td></tr><tr><td>ImageQuant LAS-4000</td><td>GE Healthcare</td><td></td><td>An imager equipped with a cooled CCD camera for detection of ECL</td></tr></tbody></table>

rab10 phosphorylation detection by lrrk2 activity using sds-page with a phosphate-binding tag

Mutaciones de la cinasa repetición rica en leucina 2 (LRRK2) han demostrado estar relacionados con la enfermedad de Parkinson familiar (FPD). Puesto que la activación anormal de la actividad quinasa de LRRK2 se ha implicado en la patogénesis de la EP, es esencial establecer un método para evaluar los niveles fisiológicos de la actividad quinasa de LRRK2. Estudios recientes revelaron que LRRK2 fosforila a miembros de la familia de Rab GTPase, incluyendo Rab10, bajo condiciones fisiológicas. Aunque la fosforilación de Rab10 endógeno de LRRK2 en células cultivadas podría detectarse por espectrometría de masas, ha sido difícil de detectar por immunoblotting debido a la pobre sensibilidad de anticuerpos específicos de fosforilación actualmente disponibles Rab10. Aquí, describimos un sencillo método para detectar los niveles endógenos de Rab10 fosforilación de LRRK2 basado en immunoblotting utilizando sodio electroforesis dodecyl del sulfato gel de poliacrilamida (SDS-PAGE) combinado con una enlace de fosfato etiqueta (P-), que es N-(5-(2-aminoethylcarbamoyl)pyridin-2-ylmetyl) -N,N',N'- tris (pyridin-2-yl-metil) - 1,3 - diaminopropan-2-ol. El presente Protocolo no sólo proporciona un ejemplo de la metodología que utiliza la etiqueta P pero también permite la evaluación de cómo mutaciones así como tratamiento y administración de inhibidor u otros factores alteran la señalización corriente abajo de LRRK2 en células y tejidos .

Sistema de sobreexpresión: Fosforilación de la HA-Rab10 por 3 × bandera-LRRK2 en HEK293 células:
Las células HEK293 fueron transfectadas con 0.266 μg de HA-Rab10 tipo de salvaje y 1.066 μg 3 × bandera LRRK2 (mutante de tipo salvaje, quinasa inactiva (K1906M), o mutantes FPD). Fosforilación de Rab10 fue examinada por etiqueta P SDS-PAGE seguido immunoblotting usando un anti-HA anticuerpo (figura 2</stro...

Watch this Scientific Journal Video about Rab10 Phosphorylation Detection by LRRK2 Activity Using SDS-PAGE with a Phosphate-binding Tag at JoVE.com

Rab10 Phosphorylation Detection by LRRK2 Activity Using SDS-PAGE with a Phosphate-binding Tag

El presente estudio describe un método sencillo de detectar niveles endógenos de la fosforilación Rab10 quinasa repetición rica en leucina 2.

Rab10 detección de fosforilación por la actividad de LRRK2 mediante SDS-PAGE con una etiqueta de enlace de fosfato

Mutations in leucine-rich repeat kinase 2 (LRRK2) have been shown to be linked with familial Parkinson&#39;s disease (FPD). Since abnormal activation of ...

rab10-phosphorylation-detection-lrrk2-activity-using-sds-page-with

Universidad San Sebastian

Research

JoVE Journal

Biochemistry

14.9K vistas.  The University of Tokyo. El presente estudio describe un método sencillo de detectar niveles endógenos de la fosforilación Rab10 quinasa repetición rica en leucina 2.

Video: Rab10 Phosphorylation Detection by LRRK2 Activity Using SDS-PAGE with a Phosphate-binding Tag

Oligopeptide Competition Assay for Phosphorylation Site Determination

Protein phosphorylation at specific sites determines its conformation and interaction with other molecules. Thus, protein phosphorylation affects biological functions and characteristics of the cell. Currently, the most common method for discovering phosphorylation sites is by liquid chromatography/mass spectrometry (LC/MS) analysis, a rapid and sensitive method. However, relatively labile phosphate moieties are often released from phosphopeptides during the fragmentation step, which often yields false-negative signals. In such cases, a traditional in vitro kinase assay using site-directed mutants would be more accurate, but this method is laborious and time-consuming. Therefore, an alternative method using peptide competition may be advantageous. The consensus recognition motif of 5&#39; adenosine monophosphate-activated protein kinase (AMPK) has been established1 and was validated using a positional scanning peptide library assay2. Thus, AMPK phosphorylation sites for a novel substrate could be predicted and confirmed by the peptide competition assays. In this report, we describe the detailed steps and procedures for the in vitro oligopeptide-competing kinase assay by illustrating AMPK-mediated nuclear factor erythroid 2-related factor 2 (Nrf2) phosphorylation. To authenticate the phosphorylation site, we carried out a sequential in vitro kinase assay using a site-specific mutant. Overall, the peptide competition assay provides a method to screen multiple potential phosphorylation sites and to identify sites for validation by the phosphorylation site mutants.

Peptide competition assays are widely used in a variety of molecular and immunological experiments. This paper describes a detailed method for an in vitro oligopeptide-competing kinase assay and the associated validation procedures, which may be useful to find specific phosphorylation sites.

Ensayo de Competencia Oligopeptídica para la Determinación del Sitio de Fosforilación

Protein phosphorylation at specific sites determines its conformation and interaction with other molecules. Thus, protein phosphorylation affects ...

Investigación

Bioquímica

Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay

Cyclin-dependent kinase 1 (Cdk1) is a master controller for the cell cycle in all eukaryotes and phosphorylates an estimated 8 - 13% of the proteome; however, the number of identified targets for Cdk1, particularly in human cells is still low. The identification of Cdk1-specific phosphorylation sites is important, as they provide mechanistic insights into how Cdk1 controls the cell cycle. Cell cycle regulation is critical for faithful chromosome segregation, and defects in this complicated process lead to chromosomal aberrations and cancer.
Here, we describe an in vitro kinase assay that is used to identify Cdk1-specific phosphorylation sites. In this assay, a purified protein is phosphorylated in vitro by commercially available human Cdk1/cyclin B. Successful phosphorylation is confirmed by SDS-PAGE, and phosphorylation sites are subsequently identified by mass spectrometry. We also describe purification protocols that yield highly pure and homogeneous protein preparations suitable for the kinase assay, and a binding assay for the functional verification of the identified phosphorylation sites, which probes the interaction between a classical nuclear localization signal (cNLS) and its nuclear transport receptor karyopherin &#945;. To aid with experimental design, we review approaches for the prediction of Cdk1-specific phosphorylation sites from protein sequences. Together these protocols present a very powerful approach that yields Cdk1-specific phosphorylation sites and enables mechanistic studies into how Cdk1 controls the cell cycle. Since this method relies on purified proteins, it can be applied to any model organism and yields reliable results, especially when combined with cell functional studies.

Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay

Cyclin-dependent kinase 1 (Cdk1) is activated in the G2 phase of the cell cycle and regulates many cellular pathways. Here, we present a protocol for an in vitro kinase assay with Cdk1, which allows the identification of Cdk1-specific phosphorylation sites for establishing cellular targets of this important kinase.

Identificación de quinasa dependiente de ciclina 1 sitios específicos de fosforilación por una quinasa In Vitro ensayo

Cyclin-dependent kinase 1 (Cdk1) is a master controller for the cell cycle in all eukaryotes and phosphorylates an estimated 8 - 13% of the proteome; ...

Human Peripheral Blood Neutrophil Isolation for Interrogating the Parkinson's Associated LRRK2 Kinase Pathway by Assessing Rab10 Phosphorylation

The leucine rich repeat kinase 2 (LRRK2) is the most frequently mutated gene in hereditary Parkinson&#8217; disease (PD) and all pathogenic LRRK2 mutations result in hyperactivation of its kinase function. Here, we describe an easy and robust assay to quantify LRRK2 kinase pathway activity in human peripheral blood neutrophils by measuring LRRK2-controlled phosphorylation of one of its physiological substrates, Rab10 at threonine 73. The immunoblotting analysis described requires a fully selective and phosphospecific antibody that recognizes the Rab10 Thr73 epitope phosphorylated by LRRK2, such as the MJFF-pRab10 rabbit monoclonal antibody. It uses human peripheral blood neutrophils, because peripheral blood is easily accessible and neutrophils are an abundant and homogenous constituent. Importantly, neutrophils express relatively high levels of both LRRK2 and Rab10. A potential drawback of neutrophils is their high intrinsic serine protease activity, which necessitates the use of very potent protease inhibitors such as the organophosphorus neurotoxin diisopropylfluorophosphate (DIFP) as part of the lysis buffer. Nevertheless, neutrophils are a valuable resource for research into LRRK2 kinase pathway activity in vivo and should be considered for inclusion into PD biorepository collections.

Mutations in the leucine rich repeat kinase 2 gene (LRRK2) cause hereditary Parkinson&#8217;s disease. We have developed an easy and robust method for assessing LRRK2-controlled phosphorylation of Rab10 in human peripheral blood neutrophils. This may help identify individuals with increased LRRK2 kinase pathway activity.

Aislamiento de Neutrófilos de Sangre Periférica Humana para Interrogar la Vía de Kinasa LRRK2 Asociada al Parkinson mediante la evaluación de la fosforilación de Rab10

The leucine rich repeat kinase 2 (LRRK2) is the most frequently mutated gene in hereditary Parkinson&#8217; disease (PD) and all pathogenic LRRK2 ...

Identification of Novel CK2 Kinase Substrates Using a Versatile Biochemical Approach

The study of kinase-substrate relationships is essential to gain a complete understanding of the functions of these enzymes and their downstream targets in both physiological and pathological states. CK2 is an evolutionarily conserved serine/threonine kinase with a growing list of hundreds of substrates involved in multiple cellular processes. Due to its pleiotropic properties, identifying and characterizing a comprehensive set of CK2 substrates has been particularly challenging and remains a hurdle in the study of this important enzyme. To address this challenge, we have devised a versatile experimental strategy that enables the targeted enrichment and identification of putative CK2 substrates. This protocol takes advantage of the unique dual co-substrate specificity of CK2 allowing for specific thiophosphorylation of its substrates in a cell or tissue lysate. These substrate proteins are subsequently alkylated, immunoprecipitated, and identified by liquid chromatography/tandem mass spectrometry (LC-MS/MS). We have previously used this approach to successfully identify CK2 substrates from Drosophila ovaries and here we extend the application of this protocol to human glioblastoma cells, illustrating the adaptability of this method to investigate the biological roles of this kinase in various model organisms and experimental systems.

The objective of this protocol is to label, enrich, and identify substrates of protein kinase CK2 from a complex biological sample such as a cell lysate or tissue homogenate. This method leverages unique aspects of CK2 biology for this purpose.

Identificación de los sustratos de quinasa CK2 novela utilizando un enfoque bioquímico versátil

The study of kinase-substrate relationships is essential to gain a complete understanding of the functions of these enzymes and their downstream targets ...

Characterization at the Molecular Level using Robust Biochemical Approaches of a New Kinase Protein

Extensive whole genome sequencing has identified many Open Reading Frames (ORFs) providing many potential proteins. These proteins may have important roles for the cell and may unravel new cellular processes. Among proteins, kinases are major actors as they belong to cell signaling pathways and have the ability to switch on or off many processes crucial to the fate of the cell, such as cell growth, division, differentiation, motility, and death.
In this study, we focused on a new potential kinase protein, LIMK2-1. We demonstrated its existence by Western Blot using a specific antibody. We evaluated its interaction with an upstream regulating protein using coimmunoprecipitation experiments. Coimmunoprecipitation is a very powerful technique able to detect the interaction between two target proteins. It may also be used to detect new partners of a bait protein. The bait protein may be purified either via a tag engineered to its sequence or via an antibody specifically targeting it. These protein complexes may then be separated by SDS-PAGE (Sodium Dodecyl Sulfate PolyAcrylamide Gel) and identified using mass spectrometry. Immunoprecipitated LIMK2-1 was also used to test its kinase activity in vitro by &#947;[32P] ATP labeling. This well-established assay may use many different substrates, and mutated versions of the bait may be used to assess the role of specific residues. The effects of pharmacological agents may also be evaluated since this technique is both highly sensitive and quantitative. Nonetheless, radioactivity handling requires particular caution. Kinase activity may also be assessed with specific antibodies targeting the phospho group of the modified amino acid. These kinds of antibodies are not commercially available for all the phospho modified residues.

We characterized a new kinase protein using robust biochemical approaches: Western Blot analysis with a dedicated specific antibody on different cell lines and tissues, interactions by coimmunoprecipitation experiments, kinase activity detected by Western Blot using a phospho-specific antibody and by &#947;[32P] ATP labeling.

Caracterización a nivel molecular utilizando enfoques bioquímicos robustos de una nueva proteína kinasa

Extensive whole genome sequencing has identified many Open Reading Frames (ORFs) providing many potential proteins. These proteins may have important ...

Non-Radioactive In Vitro Cardiac Myosin Light Chain Kinase Assays

Cardiac-specific myosin regulatory light chain kinase (cMLCK) regulates cardiac sarcomere structure and contractility by phosphorylating the ventricular isoform of the myosin regulatory light chain (MLC2v). MLC2v phosphorylation levels are significantly reduced in failing hearts, indicating the clinical importance of assessing the activity of cMLCK and the phosphorylation level of MLC2v to elucidate the pathogenesis of heart failure. This paper describes nonradioactive methods to assess both the activity of cMLCK and MLC2v phosphorylation levels. In vitro kinase reactions are performed using recombinant cMLCK with recombinant calmodulin and MLC2v in the presence of ATP and calcium at 25 &#176;C, which are followed by either a bioluminescent ADP detection assay or a phosphate-affinity SDS-PAGE. In the representative study, the bioluminescent ADP detection assay showed a strict linear increase of the signal at cMLCK concentrations between 1.25 nM to 25 nM. Phosphate-affinity SDS-PAGE also showed a linear increase of phosphorylated MLC2v in the same cMLCK concentration range. Next, the time-dependency of the reactions was examined at the concentration of 5 nM cMLCK. A bioluminescent ADP detection assay showed a linear increase in the signal during 90 min of the reaction. Similarly, phosphate-affinity SDS-PAGE showed a time-dependent increase of phosphorylated MLC2v. The biochemical parameters of cMLCK for MLC2v were determined by a Michaelis-Menten plot using the bioluminescent ADP detection assay. The Vmax was 1.65 &#177; 0.10 mol/min/mol kinase and the average Km was around 0.5 USA &#181;M at 25 &#176;C. Next, the activity of wild type and the dilated cardiomyopathy-associated p.Pro639Valfs*15 mutant cMLCK were measured. The bioluminescent ADP detection assay and phosphate-affinity SDS-PAGE correctly detected defects in cMLCK activity and MLC2v phosphorylation, respectively. In conclusion, a combination of the bioluminescent ADP detection assay and the phosphate-affinity SDS-PAGE is a simple, accurate, safe, low-cost, and flexible method to measure cMLCK activity and the phosphorylation level of MLC2v.

This study describes protocols for nonradiometric methods, a bioluminescent ADP detection assay and a phosphate-affinity SDS-PAGE, to determine the kinase activity of cardiac myosin light chain kinase (cMLCK) and the phosphorylation level of its substrate, myosin regulatory light chain (MLC2v).

Cardiac-specific myosin regulatory light chain kinase (cMLCK) regulates cardiac sarcomere structure and contractility by phosphorylating the ventricular ...

Assaying the Kinase Activity of LRRK2 in vitro

Leucine Rich Repeat Kinase 2 (LRRK2) is a 2527 amino acid member of the ROCO family of proteins, possessing a complex, multidomain structure including a GTPase domain (termed ROC, for Ras of Complex proteins) and a kinase domain1. The discovery in 2004 of mutations in LRRK2 that cause Parkinson's disease (PD) resulted in LRRK2 being the focus of a huge volume of research into its normal function and how the protein goes awry in the disease state2,3. Initial investigations into the function of LRRK2 focused on its enzymatic activities4-6. Although a clear picture has yet to emerge of a consistent alteration in these due to mutations, data from a number of groups has highlighted the importance of the kinase activity of LRRK2 in cell death linked to mutations7,8. Recent publications have reported inhibitors targeting the kinase activity of LRRK2, providing a key experimental tool9-11. In light of these data, it is likely that the enzymatic properties of LRRK2 afford us an important window into the biology of this protein, although whether they are potential drug targets for Parkinson's is open to debate.
A number of different approaches have been used to assay the kinase activity of LRRK2. Initially, assays were carried out using epitope tagged protein overexpressed in mammalian cell lines and immunoprecipitated, with the assays carried out using this protein immobilised on agarose beads4,5,7. Subsequently, purified recombinant fragments of LRRK2 in solution have also been used, for example a GST tagged fragment purified from insect cells containing residues 970 to 2527 of LRRK212. Recently, Dani&euml;ls et al. reported the isolation of full length LRRK2 in solution from human embryonic kidney cells, however this protein is not widely available13. In contrast, the GST fusion truncated form of LRRK2 is commercially available (from Invitrogen, see table 1 for details), and provides a convenient tool for demonstrating an assay for LRRK2 kinase activity. Several different outputs for LRRK2 kinase activity have been reported. Autophosphorylation of LRRK2 itself, phosphorylation of Myelin Basic Protein (MBP) as a generic kinase substrate and phosphorylation of an artificial substrate - dubbed LRRKtide, based upon phosphorylation of threonine 558 in Moesin - have all been used, as have a series of putative physiological substrates including &alpha;-synuclein, Moesin and 4-EBP14-17. The status of these proteins as substrates for LRRK2 remains unclear, and as such the protocol described below will focus on using MBP as a generic substrate, noting the utility of this system to assay LRRK2 kinase activity directed against a range of potential substrates.

Assaying the Kinase Activity of LRRK2 in vitro

Leucine Rich Repeat Kinase 2 is a large multidomain kinase, mutations in which are the most common genetic cause of Parkinson's disease. Analysis of the kinase activity of this protein has proven to be a crucial tool in understanding the biology and dysfunction of this protein. In this paper, in vitro assaying of the kinase activity of LRRK2 and a selection of its mutants is described, providing an experimental system to examine phosphorylation of putative substrates and potential dysfunction of LRRK2 in disease.

Ensayo de la actividad quinasa de LRRK2 In vitro</em

Leucine Rich Repeat Kinase 2 (LRRK2) is a 2527 amino acid member of the ROCO family of proteins, possessing a complex, multidomain structure including a ...

Biología

Metabolic Labeling of Leucine Rich Repeat Kinases 1 and 2 with Radioactive Phosphate

Leucine rich repeat kinases 1 and 2 (LRRK1 and LRRK2) are paralogs which share a similar domain organization, including a serine-threonine kinase domain, a Ras of complex proteins domain (ROC), a C-terminal of ROC domain (COR), and leucine-rich and ankyrin-like repeats at the N-terminus. The precise cellular roles of LRRK1 and LRRK2 have yet to be elucidated, however LRRK1 has been implicated in tyrosine kinase receptor signaling1,2, while LRRK2 is implicated in the pathogenesis of Parkinson's disease3,4. In this report, we present a protocol to label the LRRK1 and LRRK2 proteins in cells with 32P orthophosphate, thereby providing a means to measure the overall phosphorylation levels of these 2 proteins in cells. In brief, affinity tagged LRRK proteins are expressed in HEK293T cells which are exposed to medium containing 32P-orthophosphate. The 32P-orthophosphate is assimilated by the cells after only a few hours of incubation and all molecules in the cell containing phosphates are thereby radioactively labeled. Via the affinity tag (3xflag) the LRRK proteins are isolated from other cellular components by immunoprecipitation. Immunoprecipitates are then separated via SDS-PAGE, blotted to PVDF membranes and analysis of the incorporated phosphates is performed by autoradiography (32P signal) and western detection (protein signal) of the proteins on the blots. The protocol can readily be adapted to monitor phosphorylation of any other protein that can be expressed in cells and isolated by immunoprecipitation.

Leucine rich repeat kinases 1 and 2 (LRRK1 and LRRK2) are multidomain proteins which encode both GTPase and kinase domains and which are phosphorylated in cells. Here, we present a protocol to label LRRK1 and LRRK2 in cells with 32P orthophosphate, thereby providing a means to measure their overall cellular phophorylation levels.

Metabólicas etiquetado de repeticiones ricas en leucina quinasas 1 y 2 con Radioactive Fosfato

Leucine rich repeat kinases 1 and 2 (LRRK1 and LRRK2) are paralogs which share a similar domain organization, including a serine-threonine kinase domain, ...

A High Resolution Method to Monitor Phosphorylation-dependent Activation of IRF3

The IRF3 transcription factor is critical for the first line of defense against pathogens mainly through interferon &#946; and antiviral gene expression. A detailed analysis of IRF3 activation is essential to understand how pathogens induce or evade the innate antiviral response. Distinct activated forms of IRF3 can be distinguished based on their phosphorylation and monomer vs dimer status. In vivo discrimination between the different activated species of IRF3 can be achieved through the separation of IRF3 phosphorylated forms based on their mobility shifts on SDS-PAGE. Additionally, the levels of IRF3 monomer and dimer can be monitored using non-denaturing electrophoresis. Here, we detail a procedure to reach the highest resolution to gain the most information regarding IRF3 activation status. This is achieved through the combination of a high resolution SDS-PAGE and a native-PAGE coupled to immunoblots using multiple total and phosphospecific antibodies. This experimental strategy constitutes an affordable and sensitive approach to acquire all the necessary information for a complete analysis of the phosphorylation-mediated activation of IRF3.

Here we describe a procedure allowing a detailed analysis of the phosphorylation-dependent activation of the IRF3 transcription factor. This is achieved through the combination of a high resolution SDS-PAGE and a native-PAGE coupled to immunoblots using multiple phosphospecific antibodies.

Una alta resolución Método de Seguimiento activación fosforilación dependiente de IRF3

The IRF3 transcription factor is critical for the first line of defense against pathogens mainly through interferon &#946; and antiviral gene expression. ...

Single-Molecule Pull-Down Assay for Protein Phosphorylation Analysis: A High Throughput Technique to Quantify Protein Phosphorylation in Cell Lysate

Source: Bailey, E. M. et al., <a href="https://www-jove-com.bdigitaluss.remotexs.co/v/63665">An Optimized Single-Molecule Pull-Down Assay for Quantification of Protein Phosphorylation.</a> J. Vis. Exp. (2022)
This video demonstrates a sensitive quantification technique of protein phosphorylation using a single-molecule pull-down assay. The functionalization of polyethylene glycol-biotin and the use of labeled antibodies increases the detection of phosphorylated tyrosine with specificity.

Ensayo pull-down de molécula única para el análisis de fosforilación de proteínas: una técnica de alto rendimiento para cuantificar la fosforilación de proteínas en el lisado celular

Source: Bailey, E. M. et al., An Optimized Single-Molecule Pull-Down Assay for Quantification of Protein Phosphorylation. J. Vis. Exp. (2022)
This video ...