אנו מודים גם למייקל ג&#39;יי פוקס קרן תמיכה במחקר זה. אנו מודים לקרן המחקר - פלנדריה FWO (פרויקט FWO G.0666.09, מלגת חוקר בכירה לJMT), Neuro-TARGET פרויקט IWT SBO/80020, לובן KU (OT/08/052A וIOF-KP/07 / 001) על תמיכתם. מחקר זה נתמך גם בחלקו על ידי קרן Druwé-Eerdekens מנוהל על ידי קרן המלך בודואן לJMT.

<ol>
	<li>Hanafusa, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Leucine-rich+repeat+kinase+LRRK1+regulates+endosomal+trafficking+of+the+EGF+receptor.">Leucine-rich repeat kinase LRRK1 regulates endosomal trafficking of the EGF receptor.</a> Nat Commun. 2, 158 (2011).</li><li>Titz, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+proximal+signaling+network+of+the+BCR-ABL1+oncogene+shows+a+modular+organization.">The proximal signaling network of the BCR-ABL1 oncogene shows a modular organization.</a> Oncogene. 29, 5895-5910 (2010).</li><li>Cookson, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+leucine-rich+repeat+kinase+2+(LRRK2)+in+Parkinson's+disease.">The role of leucine-rich repeat kinase 2 (LRRK2) in Parkinson's disease.</a> Nat Rev Neurosci. 11, 791-797 (2010).</li><li>Taymans, J. M., Cookson, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanisms+of+dominant+parkinsonism;+the+toxic+triangle+of+LRRK2,+alpha-synuclein+and+tau.">Mechanisms of dominant parkinsonism; the toxic triangle of LRRK2, alpha-synuclein and tau.</a> Bioessays. 32, 227-235 (2010).</li><li>Lewis, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+function+of+ROCO+proteins+in+health+and+disease.">The function of ROCO proteins in health and disease.</a> Biol Cell. 101, 183-191 (2009).</li><li>Marin, I., van Egmond, W. N., van Haastert, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Roco+protein+family:+a+functional+perspective.">The Roco protein family: a functional perspective.</a> FASEB J. 22, 3103-3110 (2008).</li><li>Marin, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Parkinson+disease+gene+LRRK2:+evolutionary+and+structural+insights.">The Parkinson disease gene LRRK2: evolutionary and structural insights.</a> Mol.Biol.Evol. 23, 2423-2433 (2006).</li><li>Marin, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ancient+origin+of+the+Parkinson+disease+gene+LRRK2.">Ancient origin of the Parkinson disease gene LRRK2.</a> J Mol Evol. 67, 41-50 (2008).</li><li>Lobbestael, E., Baekelandt, V., Taymans, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phosphorylation+of+LRRK2:+from+kinase+to+substrate.">Phosphorylation of LRRK2: from kinase to substrate.</a> Biochem Soc Trans. 40, 1102-1110 (2012).</li><li>Gloeckner, C. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phosphopeptide+Analysis+Reveals+Two+Discrete+Clusters+of+Phosphorylation+in+the+N-Terminus+and+the+Roc+Domain+of+the+Parkinson-Disease+Associated+Protein+Kinase+LRRK2.">Phosphopeptide Analysis Reveals Two Discrete Clusters of Phosphorylation in the N-Terminus and the Roc Domain of the Parkinson-Disease Associated Protein Kinase LRRK2.</a> J Proteome Res. 9, 1738-1745 (2010).</li><li>Nichols, R. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=14-3-3+binding+to+LRRK2+is+disrupted+by+multiple+Parkinson's+disease-associated+mutations+and+regulates+cytoplasmic+localization.">14-3-3 binding to LRRK2 is disrupted by multiple Parkinson's disease-associated mutations and regulates cytoplasmic localization.</a> Biochem J. 430, 393-404 (2010).</li><li>Greggio, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mutations+in+LRRK2/dardarin+associated+with+Parkinson+disease+are+more+toxic+than+equivalent+mutations+in+the+homologous+kinase+LRRK1.">Mutations in LRRK2/dardarin associated with Parkinson disease are more toxic than equivalent mutations in the homologous kinase LRRK1.</a> J.Neurochem. 102, 93-102 (2007).</li><li>Taymans, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=LRRK2+Kinase+Activity+Is+Dependent+on+LRRK2+GTP+Binding+Capacity+but+Independent+of+LRRK2+GTP+Binding.">LRRK2 Kinase Activity Is Dependent on LRRK2 GTP Binding Capacity but Independent of LRRK2 GTP Binding.</a> PLoS One. 6, 23207-23 (2011).</li><li>Dani&#235;ls, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insight+into+the+mode+of+action+of+the+LRRK2+Y1699C+pathogenic+mutant.">Insight into the mode of action of the LRRK2 Y1699C pathogenic mutant.</a> J Neurochem. 116, 304-315 (2011).</li><li>Civiero, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biochemical+characterization+of+highly+purified+leucine-rich+repeat+kinases+1+and+2+demonstrates+formation+of+homodimers.">Biochemical characterization of highly purified leucine-rich repeat kinases 1 and 2 demonstrates formation of homodimers.</a> PLoS One. 7, e43472 (2012).</li><li>Taymans, J. M., Van den Haute, C., Baekelandt, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distribution+of+PINK1+and+LRRK2+in+rat+and+mouse+brain.">Distribution of PINK1 and LRRK2 in rat and mouse brain.</a> J.Neurochem. 98, 951-961 (2006).</li><li>Lewis, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assaying+the+kinase+activity+of+LRRK2+in+vitro.">Assaying the kinase activity of LRRK2 in vitro.</a> J Vis Exp. , (2012).</li><li>Lobbestael, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immunohistochemical+detection+of+transgene+expression+in+the+brain+using+small+epitope+tags.">Immunohistochemical detection of transgene expression in the brain using small epitope tags.</a> BMC Biotechnol. 10, 16 (2010).</li><li>Davies, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comprehensive+Characterization+and+Optimization+of+Leucine+Rich+Repeat+Kinase+2+(LRRK2)+Monoclonal+Antibodies.">Comprehensive Characterization and Optimization of Leucine Rich Repeat Kinase 2 (LRRK2) Monoclonal Antibodies.</a> Biochem J. , (2013).</li><li>West, A. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Parkinson's+disease-associated+mutations+in+LRRK2+link+enhanced+GTP-binding+and+kinase+activities+to+neuronal+toxicity.">Parkinson's disease-associated mutations in LRRK2 link enhanced GTP-binding and kinase activities to neuronal toxicity.</a> Hum.Mol.Genet. 16, 223-232 (2007).</li><li>Sheng, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ser1292+autophosphorylation+is+an+indicator+of+LRRK2+kinase+activity+and+contributes+to+the+cellular+effects+of+PD+mutations.">Ser1292 autophosphorylation is an indicator of LRRK2 kinase activity and contributes to the cellular effects of PD mutations.</a> Sci Transl Med. 4, 164ra161 (2012).</li><li>Li, X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phosphorylation-dependent+14-3-3+binding+to+LRRK2+is+impaired+by+common+mutations+of+familial+Parkinson's+disease.">Phosphorylation-dependent 14-3-3 binding to LRRK2 is impaired by common mutations of familial Parkinson's disease.</a> PLoS One. 6, e17153 (2011).</li><li>Dzamko, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inhibition+of+LRRK2+kinase+activity+leads+to+dephosphorylation+of+Ser(910)/Ser(935),+disruption+of+14-3-3+binding+and+altered+cytoplasmic+localization.">Inhibition of LRRK2 kinase activity leads to dephosphorylation of Ser(910)/Ser(935), disruption of 14-3-3 binding and altered cytoplasmic localization.</a> Biochem J. 430 (910), 405-413 (2010).</li></ol>

יש מחברים אין לחשוף.

מאמר זה מספק פרוטוקול בסיסי למנסה לאמוד רמת זירחון הכללית של LRRK1 וLRRK2 בשורות תאים באמצעות תיוג חילוף חומרים עם 32 P-orthophosphate. האסטרטגיה הכוללת היא פשוטה. זיקה מתויגת חלבוני LRRK באים לידי ביטוי בתאי HEK293T החשופים למדיום המכיל 32 P-orthophosphate. 32 P-orthophosphate נטמע על ...

<html> קינאזות אוצין העשיר החוזרת 1 ו -2 (LRRK1 וLRRK2) הם paralogs multidomain אשר חולק ארגון תחום דומה. שני החלבונים לקודד רצף GTPase דומה למשפחת ראס של GTPases (ראס של חלבונים מורכבים, או ROC), כמו גם בטרמינל C-של תחום ROC (COR), ביעילות סיווג שני החלבונים למשפחת חלבוני Roco 5,6. N-מסוף של טנדם תחום ROC-COR, שני החלבונים לקודד תחום חוזר לאוצין עשיר, כמו גם תחום כמו ankyrin-, בעוד שרק LRRK2 מקודד ארמדיל נוסף domein 6-8. בטרמינל C-של ROC-COR, שני החלבונים לשתף תחום קינאז סרין-תראונין בעוד שרק LRRK2 מקודד תחום WD40 באזור טרמינל C-8. התפקידים הסלולריים המדויקים של LRRK1 וLRRK2 עדיין לא הובהר, עם זאת LRRK1 היה מעורב בקולטן טירוזין קינאז איתות 1,2, בעוד נקודות ראיות גנטיות לתפקיד לLRRK2 בפתוגנזה של מחלת פרקינסון 3,4. class = &quot;jove_content&quot;&gt; זירחון של חלבונים הוא מנגנון רגולציה משותף בתאים. לדוגמא, זרחון יכול להיות חיוני להפעלה של אנזימים או לגיוס של חלבונים מורכבים איתות. זירחון הסלולרי של LRRK2 התאפיין בהרחבה ומיפוי phosphosite הראה רוב אתרי זירחון הסלולרי להתרחש באשכול בין חוזר ankyrin ותחומים חוזרים עשירים לאוצין 9-11. למרות שאתרי זירחון הסלולרי LRRK1 עדיין לא ממופים, ראיות ממחקרים באמצעות מכתים phosphoprotein של כתמי חלבון LRRK1 immunoprecipitated של מתאי COS7 מצביעות על כך שחלבון LRRK1 פוספורילציה בתאים 12. מאמר זה מספק פרוטוקול בסיסי למנסה לאמוד רמת זירחון הכללית של LRRK1 וLRRK2 בשורות תאים באמצעות תיוג חילוף חומרים עם 32 P-orthophosphate. האסטרטגיה הכוללת היא פשוטה. זיקה מתויגת הגנה של מחזור LRRKתוספות באות לידי ביטוי בתאי HEK293T החשופים למדיום המכיל 32 P-orthophosphate. 32 P-orthophosphate נטמע על ידי התאים רק לאחר כמה שעות של דגירה וכל המולקולות בתא המכיל פוספטים מסומנים ובכך רדיואקטיבית. תג הזיקה (3xflag) לאחר מכן נעשה שימוש כדי לבודד את חלבוני LRRK ממרכיבים תאיים אחרים על ידי immunoprecipitation. Immunoprecipitates אז מופרדים באמצעות SDS-PAGE, מחק לממברנות PVDF וניתוח של פוספטים המשולבים מתבצע על ידי autoradiography (אות 32 P) וזיהוי מערבי (אות חלבון) של החלבונים בכתמים.

<table><tbody><tr><td>Phosphorus-32 Radionuclide, 1 mCi, buffer disodiumphosphate in 1 ml water</td><td>Perkin Elmer</td><td>NEX011001MC</td><td></td></tr><tr><td>Dulbecco&amp;#8217;s Modified Eagle Medium (D-MEM) (1X), liquid (high glucose)</td><td>Invitrogen</td><td>11971-025</td><td>This medium contains no phosphates</td></tr><tr><td>Anti Flag M2 affiinty gel</td><td>Sigma</td><td>A2220</td><td>For an equivalent product with red colored gel (useful to more easily visualize the beads), use cat. No. F2426.</td></tr><tr><td>Extra thick blotting filter</td><td>Bio-Rad</td><td>1703965</td><td></td></tr><tr><td>Ponceau S solution</td><td>Sigma</td><td>P7170</td><td></td></tr></tbody></table>

metabolic labeling of leucine rich repeat kinases 1 and 2 with radioactive phosphate

קינאזות אוצין החוזרת עשיר 1 ו -2 (LRRK1 וLRRK2) הם paralogs אשר חולק ארגון תחום דומה, לרבות תחום קינאז סרין-תראונין, ראס של תחום חלבונים מורכב (ROC), C-מסוף של תחום ROC (COR), ולאוצין עשיר וחוזר כמו ankyrin-בN-הסופית. התפקידים הסלולריים המדויקים של LRRK1 וLRRK2 עדיין לא הובהר, עם זאת LRRK1 היה מעורב בקולטן טירוזין קינאז איתות 1,2, בעוד LRRK2 הוא מעורב בפתוגנזה של מחלת פרקינסון 3,4. בדו&quot;ח זה, אנו מציגים פרוטוקול לתייג חלבוני LRRK1 וLRRK2 בתאים עם 32 orthophosphate P, ובכך לספק אמצעים כדי למדוד את רמות זירחון הכוללות של 2 החלבונים האלה בתאים. בקיצור, זיקה מתויגת חלבוני LRRK באים לידי ביטוי בתאי HEK293T החשופים למדיום המכיל 32 P-orthophosphate. 32 P-orthophosphate נטמע על ידי התאים רק לאחר כמהשעות של דגירה וכל המולקולות בתא המכיל פוספטים מסומנות ובכך רדיואקטיבית. באמצעות תג הזיקה (3xflag) חלבוני LRRK מבודדים ממרכיבים תאיים אחרים על ידי immunoprecipitation. Immunoprecipitates אז מופרדים באמצעות SDS-PAGE, מחק לממברנות PVDF וניתוח של פוספטים המשולבים מתבצע על ידי autoradiography (אות 32 P) וזיהוי מערבי (אות חלבון) של החלבונים בכתמים. הפרוטוקול יכול בקלות להיות מותאם כדי לפקח זירחון של כל חלבון אחר שיכול לבוא לידי ביטוי בתאים ומבודד על ידי immunoprecipitation.

<html> על מנת להשוות רמות זירחון הכוללות של LRRK1 וLRRK2 בתאים, 3xflag מתויג LRRK1 וLRRK2 בא לידי ביטוי בתאי HEK293T 15. תאים בתרבית 6 צלחות היטב ומסומן עם 32 P ונותחו כפי שתוארו לעיל בטקסט הפרוטוקול. איור 1 מציג תוצאות נציג לתיוג המטבולית של LRRK1 וLRRK2 בתאי HEK293T. התאגדות פוס?...

Watch this Scientific Journal Video about Metabolic Labeling of Leucine Rich Repeat Kinases 1 and 2 with Radioactive Phosphate at JoVE.com

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

קינאזות אוצין העשיר החוזרת 1 ו -2 (LRRK1 וLRRK2) הם חלבוני multidomain אשר לקודד שני GTPase ותחומים קינאז ואשר פוספורילציה בתאים. כאן, אנו מציגים פרוטוקול לתייג LRRK1 וLRRK2 בתאים עם 32 orthophosphate P, ובכך לספק אמצעים כדי למדוד את רמות phophorylation הסלולרי הכוללות שלהם.

מטבולית תיוג של אוצין עשיר חזור קינאזות 1 ו -2 עם רדיואקטיבי פוספט

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

metabolic-labeling-leucine-rich-repeat-kinases-1-2-with-radioactive

Universidad de Cartagena UDEC

Research

Education

JoVE Journal

JoVE Core

Chemistry

Biology

Radioactivity and Nuclear Chemistry

SCIENTISTS IN ACTION

9.9K Views.  KU Leuven and Leuven Institute for Neuroscience and Disease (LIND).  קינאזות אוצין העשיר החוזרת 1 ו -2 (LRRK1 וLRRK2) הם חלבוני multidomain אשר לקודד שני GTPase ותחומים קינאז ואשר פוספורילציה בתאים. כאן, אנו מציגים פרוטוקול לתייג LRRK1 וLRRK2 בתאים עם 32 orthophosphate P, ובכך לספק אמצעים כדי למדוד את רמות phophorylation הסלולרי הכוללות ש?...

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

Nuclear Magnetic Resonance Spectroscopy for the Identification of Multiple Phosphorylations of Intrinsically Disordered Proteins

Aggregates of the neuronal Tau protein are found inside neurons of Alzheimer's disease patients. Development of the disease is accompanied by increased, abnormal phosphorylation of Tau. In the course of the molecular investigation of Tau functions and dysfunctions in the disease, nuclear magnetic resonance (NMR) spectroscopy is used to identify the multiple phosphorylations of Tau. We present here detailed protocols of recombinant production of Tau in bacteria, with isotopic enrichment for NMR studies. Purification steps that take advantage of Tau's heat stability and high isoelectric point are described. The protocol for in vitro phosphorylation of Tau by recombinant activated ERK2 allows for generating multiple phosphorylations. The protein sample is ready for data acquisition at the issue of these steps. The parameter setup to start recording on the spectrometer is considered next. Finally, the strategy to identify phosphorylation sites of modified Tau, based on NMR data, is explained. The benefit of this methodology compared to other techniques used to identify phosphorylation sites, such as immuno-detection or mass spectrometry (MS), is discussed.

We describe here a method to identify multiple phosphorylations of an intrinsically disordered protein by Nuclear Magnetic Resonance Spectroscopy (NMR), using Tau protein as a case study. Recombinant Tau is isotopically enriched and modified in vitro by a kinase prior to data acquisition and analysis.

ספקטרוסקופיה הגרעיני תהודה מגנטית עבור זיהוי של Phosphorylations המרובה של חלבונים לא תקינים מהותיים

Aggregates of the neuronal Tau protein are found inside neurons of Alzheimer's disease patients. Development of the disease is accompanied by increased, ...

Biochemistry

Assaying Protein Kinase Activity with Radiolabeled ATP

Protein kinases are able to govern large-scale cellular changes in response to complex arrays of stimuli, and much effort has been directed at uncovering allosteric details of their regulation. Kinases comprise signaling networks whose defects are often hallmarks of multiple forms of cancer and related diseases, making an assay platform amenable to manipulation of upstream regulatory factors and validation of reaction requirements critical in the search for improved therapeutics. Here, we describe a basic kinase assay that can be easily adapted to suit specific experimental questions including but not limited to testing the effects of biochemical and pharmacological agents, genetic manipulations such as mutation and deletion, as well as cell culture conditions and treatments to probe cell signaling mechanisms. This assay utilizes radiolabeled [&#947;-32P] ATP, which allows for quantitative comparisons and clear visualization of results, and can be modified for use with immunoprecipitated or recombinant kinase, specific or typified substrates, all over a wide range of reaction conditions.

Protein kinases are highly evolved signaling enzymes and scaffolds that are critical for inter- and intracellular signal transduction. We present a protocol for measuring kinase activity through the use of radiolabeled adenosine triphosphate ([&#947;-32P] ATP), a reliable method to aid in elucidation of cellular signaling regulation.

Assaying חלבון פעילות עם Kinase Radiolabeled

Protein kinases are able to govern large-scale cellular changes in response to complex arrays of stimuli, and much effort has been directed at uncovering ...

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

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 the kinase activity of LRRK2 has been implicated in the pathogenesis of PD, it is essential to establish a method to evaluate the physiological levels of the kinase activity of LRRK2. Recent studies revealed that LRRK2 phosphorylates members of the Rab GTPase family, including Rab10, under physiological conditions. Although the phosphorylation of endogenous Rab10 by LRRK2 in cultured cells could be detected by mass spectrometry, it has been difficult to detect it by immunoblotting due to the poor sensitivity of currently available phosphorylation-specific antibodies for Rab10. Here, we describe a simple method of detecting the endogenous levels of Rab10 phosphorylation by LRRK2 based on immunoblotting utilizing sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) combined with a phosphate-binding tag (P-tag), which is N-(5-(2-aminoethylcarbamoyl)pyridin-2-ylmetyl)-N,N&#39;,N&#39;-tris(pyridin-2-yl-methyl)-1,3-diaminopropan-2-ol. The present protocol not only provides an example of the methodology utilizing the P-tag but also enables the assessment of how mutations as well as inhibitor treatment/administration or any other factors alter the downstream signaling of LRRK2 in cells and tissues.

The present study describes a simple method of detecting endogenous levels of Rab10 phosphorylation by leucine-rich repeat kinase 2.

Rab10 זיהוי זרחון על-ידי פעילות LRRK2 באמצעות מרחביות-דף עם תג מחייב פוספט

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 ...

Radiolabeling and Quantification of Cellular Levels of Phosphoinositides by High Performance Liquid Chromatography-coupled Flow Scintillation

Phosphoinositides (PtdInsPs) are essential signaling lipids responsible for recruiting specific effectors and conferring organelles with molecular identity and function. Each of the seven PtdInsPs varies in their distribution and abundance, which are tightly regulated by specific kinases and phosphatases. The abundance of PtdInsPs can change abruptly in response to various signaling events or disturbance of the regulatory machinery. To understand how these events lead to changes in the amount of PtdInsPs and their resulting impact, it is important to quantify PtdInsP levels before and after a signaling event or between control and abnormal conditions. However, due to their low abundance and similarity, quantifying the relative amounts of each PtdInsP can be challenging. This article describes a method for quantifying PtdInsP levels by metabolically labeling cells with 3H-myo-inositol, which is incorporated into PtdInsPs. Phospholipids are then precipitated and deacylated. The resulting soluble 3H-glycero-inositides are further extracted, separated by high-performance liquid chromatography (HPLC), and detected by flow scintillation. The labeling and processing of yeast samples is described in detail, as well as the instrumental setup for the HPLC and flow scintillator. Despite losing structural information regarding acyl chain content, this method is sensitive and can be optimized to concurrently quantify all seven PtdInsPs in cells.

Phosphoinositides are signaling lipids whose relative abundance rapidly changes in response to various stimuli. This article describes a method to measure the abundance of phosphoinositides by metabolically labeling cells with 3H-myo-inositol, followed by extraction and deacylation. Extracted glycero-inositides are then separated by high-performance liquid chromatography and quantified by flow scintillation.

Radiolabeling וכימות של רמות סלולריות של Phosphoinositides ידי נצנץ זרימה מצמיד כרומטוגרפיה נוזלית ביצועים גבוהים

Phosphoinositides (PtdInsPs) are essential signaling lipids responsible for recruiting specific effectors and conferring organelles with molecular ...

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.

אפיון ברמה המולקולרית באמצעות גישות ביוכימיות איתנות של חלבון קינאז חדש

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 ...

Nonradioactive Assay to Measure Polynucleotide Phosphorylation of Small Nucleotide Substrates

Polynucleotide kinases (PNKs) are enzymes that catalyze the phosphorylation of the 5&#39; hydroxyl end of DNA and RNA oligonucleotides. The activity of PNKs can be quantified using direct or indirect approaches. Presented here is a direct, in vitro approach to measure PNK activity that relies on a fluorescently-labeled oligonucleotide substrate and polyacrylamide gel electrophoresis. This approach provides resolution of the phosphorylated products while avoiding the use of radiolabeled substrates. The protocol details how to set up the phosphorylation reaction, prepare and run large polyacrylamide gels, and quantify the reaction products. The most technically challenging part of this assay is pouring and running the large polyacrylamide gels; thus, important details to overcome common difficulties are provided. This protocol was optimized for Grc3, a PNK that assembles into an obligate pre-ribosomal RNA processing complex with its binding partner, the Las1 nuclease. However, this protocol can be adapted to measure the activity of other PNK enzymes. Moreover, this assay can also be modified to determine the effects of different components of the reaction, such as the nucleoside triphosphate, metal ions, and oligonucleotides.

This protocol describes a nonradioactive assay to measure kinase activity of polynucleotide kinases (PNKs) on small DNA and RNA substrates.

תרגום לא רדיואקטיבי למדוד פוספורילציה פולינוקלאוטיד של מצעי נוקלאוטיד קטנים

Polynucleotide kinases (PNKs) are enzymes that catalyze the phosphorylation of the 5&#39; hydroxyl end of DNA and RNA oligonucleotides. The activity of ...

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.

Assaying פעילות קינאז של LRRK2 במבחנה</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 ...

Metabolic Pathway Confirmation and Discovery Through 13C-labeling of Proteinogenic Amino Acids

Microbes have complex metabolic pathways that can be investigated using biochemistry and functional genomics methods. One important technique to examine cell central metabolism and discover new enzymes is 13C-assisted metabolism analysis 1. This technique is based on isotopic labeling, whereby microbes are fed with a 13C labeled substrates. By tracing the atom transition paths between metabolites in the biochemical network, we can determine functional pathways and discover new enzymes. 
As a complementary method to transcriptomics and proteomics, approaches for isotopomer-assisted analysis of metabolic pathways contain three major steps 2. First, we grow cells with 13C labeled substrates. In this step, the composition of the medium and the selection of labeled substrates are two key factors. To avoid measurement noises from non-labeled carbon in nutrient supplements, a minimal medium with a sole carbon source is required. Further, the choice of a labeled substrate is based on how effectively it will elucidate the pathway being analyzed. Because novel enzymes often involve different reaction stereochemistry or intermediate products, in general, singly labeled carbon substrates are more informative for detection of novel pathways than uniformly labeled ones for detection of novel pathways3, 4. Second, we analyze amino acid labeling patterns using GC-MS. Amino acids are abundant in protein and thus can be obtained from biomass hydrolysis. Amino acids can be derivatized by N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide (TBDMS) before GC separation. TBDMS derivatized amino acids can be fragmented by MS and result in different arrays of fragments. Based on the mass to charge (m/z) ratio of fragmented and unfragmented amino acids, we can deduce the possible labeled patterns of the central metabolites that are precursors of the amino acids. Third, we trace 13C carbon transitions in the proposed pathways and, based on the isotopomer data, confirm whether these pathways are active 2. Measurement of amino acids provides isotopic labeling information about eight crucial precursor metabolites in the central metabolism. These metabolic key nodes can reflect the functions of associated central pathways.
13C-assisted metabolism analysis via proteinogenic amino acids can be widely used for functional characterization of poorly-characterized microbial metabolism1. In this protocol, we will use Cyanothece 51142 as the model strain to demonstrate the use of labeled carbon substrates for discovering new enzymatic functions.

Metabolic Pathway Confirmation and Discovery Through 13C-labeling of Proteinogenic Amino Acids

13C-isotope labeling is a useful technique for determining the cell central metabolism for various types of microorganisms. After cells have been cultured with a specific labeled substrate, GC-MS measurement can reveal functional metabolic pathways based on unique labeling patterns in proteinogenic amino acids.

מסלול אישור דיסקברי מטבולית ודרך 13 C-תיוג של חומצות אמינו Proteinogenic

Microbes have complex metabolic pathways that can be investigated using biochemistry and functional genomics methods. One important technique to examine ...

Protease- and Acid-catalyzed Labeling Workflows Employing 18O-enriched Water

Stable isotopes are essential tools in biological mass spectrometry. Historically, 18O-stable isotopes have been extensively used to study the catalytic mechanisms of proteolytic enzymes1-3. With the advent of mass spectrometry-based proteomics, the enzymatically-catalyzed incorporation of 18O-atoms from stable isotopically enriched water has become a popular method to quantitatively compare protein expression levels (reviewed by Fenselau and Yao4, Miyagi and Rao5 and Ye et al.6). 18O-labeling constitutes a simple and low-cost alternative to chemical (e.g. iTRAQ, ICAT) and metabolic (e.g. SILAC) labeling techniques7. Depending on the protease utilized, 18O-labeling can result in the incorporation of up to two 18O-atoms in the C-terminal carboxyl group of the cleavage product3. The labeling reaction can be subdivided into two independent processes, the peptide bond cleavage and the carboxyl oxygen exchange reaction8. In our PALeO (protease-assisted labeling employing 18O-enriched water) adaptation of enzymatic 18O-labeling, we utilized 50% 18O-enriched water to yield distinctive isotope signatures. In combination with high-resolution matrix-assisted laser desorption ionization time-of-flight tandem mass spectrometry (MALDI-TOF/TOF MS/MS), the characteristic isotope envelopes can be used to identify cleavage products with a high level of specificity. We previously have used the PALeO-methodology to detect and characterize endogenous proteases9 and monitor proteolytic reactions10-11. Since PALeO encodes the very essence of the proteolytic cleavage reaction, the experimental setup is simple and biochemical enrichment steps of cleavage products can be circumvented. The PALeO-method can easily be extended to (i) time course experiments that monitor the dynamics of proteolytic cleavage reactions and (ii) the analysis of proteolysis in complex biological samples that represent physiological conditions. PALeO-TimeCourse experiments help identifying rate-limiting processing steps and reaction intermediates in complex proteolytic pathway reactions. Furthermore, the PALeO-reaction allows us to identify proteolytic enzymes such as the serine protease trypsin that is capable to rebind its cleavage products and catalyze the incorporation of a second 18O-atom. Such "double-labeling" enzymes can be used for postdigestion 18O-labeling, in which peptides are exclusively labeled by the carboxyl oxygen exchange reaction. Our third strategy extends labeling employing 18O-enriched water beyond enzymes and uses acidic pH conditions to introduce 18O-stable isotope signatures into peptides.

Protease- and Acid-catalyzed Labeling Workflows Employing 18O-enriched Water

Stable isotope labeling workflows employing 18O-enriched water (LeO-workflows) are versatile tools for quantitative and qualitative proteomics studies. In protease-assisted (PALeO) workflows, 18O-atoms are introduced by proteolytic cleavage and carboxyl oxygen exchange reactions mediated by proteases. In the acid-catalyzed (ALeO) workflow, 18O-atoms are introduced by carboxyl oxygen exchange at low pH.

פרוטאז וחומצת קטליזאטור זרימות עבודת תיוג המעסיק<sup&gt; 18</supמים&gt; O-מועשר

Stable isotopes are essential tools in biological mass spectrometry. Historically, 18O-stable isotopes have been extensively used to study the catalytic ...

מטבולית תיוג של אוצין עשיר חזור קינאזות 1 ו -2 עם רדיואקטיבי פוספט

Summary

Explore More Videos

Chapters in this video