Name: a functional assay for gap junctional examination; electroporation of adherent cells on indium-tin oxide
Uploaded: 2014-10-18T15:00:00.000+00:00
Duration: 11 min 2 s
Description: Watch this Scientific Journal Video about A Functional Assay for Gap Junctional Examination; Electroporation of Adherent Cells on Indium-Tin Oxide at JoVE.com

We thank Lowell Cochran for expert videography assistance. The financial assistance of the Canadian Institutes of Health Research (CIHR), the Canadian Breast Cancer Foundation (CBCF, Ontario Chapter), the Natural Sciences and Engineering Research Council of Canada (NSERC), the Canadian Breast Cancer Research Alliance, the Ontario Centers of Excellence, the Breast Cancer Action Kingston and the Clare Nelson bequest fund through grants to LR is gratefully acknowledged. SG was the recipient of an NSERC studentship. MG was supported by a postdoctoral fellowship from the US Army Breast Cancer Program, the Ministry of Research and Innovation of the Province of Ontario and the Advisory Research Committee of Queen&#8217;s University.

1 ציפוי התאים בלשכות Electroporation <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> במינרית זרימת מכסה המנוע, trypsinize התאים באמצעות טכניקה סטרילית כרגיל. הערה: חשוב מאוד לחסל על ידי צנטריפוגה כל העקבות של טריפסין, משום שהם עלולים לעכב התפשטות התאים על הזכוכית, ומכאן ההיווצרות של adherens וצמתים פער. </li><li style=";text-align:right;direction:rtl"> 1 פיפטה מ&quot;ל של ההשעיה התא בתאי electroporation סטרילי מסופקים עם בelectroporator אתרו (איור 1), ומקום בC 37 o, CO 2 באינקובטור. הערה: הידבקות תא ניתן לשפר על ידי ציפוי על פיברונקטין, קולגן, פולי ליזין או דבק תאים ורקמות (ראה לוח חומרים). </li><li style=";text-align:right;direction:rtl"> כאשר התאים יצרו שכבה ומחוברות הם מוכנים לבחינת GJIC. </li></ol> .2 Electroporation נוהל Electroporation לבדיקת GJIC יכולה להתנהל מחוץ למינרית זרימת מכסה המנוע,מאז זה לוקח רק כמה דקות. אם פעמים דגירה ארוכות יותר נדרשות לניסוי ספציפי, אז זה יכול להיות שנערך כולו בעלעלי זרימת מכסה המנוע. בכל המקרים, התאים שבו התאים גדלים חייבים להיות סטרילי. <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> הכן / פתרון צהוב לוציפר 5 מ&quot;ג מ&quot;ל: ממיסים אבקת 10 מ&quot;ג LY (מסופקת עם electroporator) ב2 מ&quot;ל מדיום גידול ללא סידן. בניסויים שדורש פעמים דגירה ארוכות יותר, מסנן לעקר את הפתרון ולאחסן ב 4 מעלות צלסיוס </li><li style=";text-align:right;direction:rtl"> לשאוב את מדיום הגידול ולשטוף את התאים עם מדיום ללא סידן, נזהר שלא לשרוט את monolayer או לייבש את התאים. אם התאים מיובשים יש להם בדרך כלל גרעינים כהים יותר ולהרים LY ללא electroporation. ההשפעה בולטת יותר באמצע השקופית שיותר חשופה לטיוטות אוויר (איור 4F). </li><li style=";text-align:right;direction:rtl"> עם pipettor אפנדורף, פיפטה פתרון הצבע לתאים (400 μl לכל התא), בקצה של החדר, being נזהר שלא לגעת בשכבת התאים. </li><li style=";text-align:right;direction:rtl"> מניחים את החדר בבעל שסופק עם electroporator ולהחיל דופק של הכוח המתאים (ראה דיון). </li><li style=";text-align:right;direction:rtl"> זהירות לשאוב חלק מפתרון LY. זה ניתן לעשות שימוש חוזר בפעם שנייה לניסויים פחות חשובים. </li><li style=";text-align:right;direction:rtl"> להוסיף ללא DMEM סידן המכיל סרום 10% dialysed. </li><li style=";text-align:right;direction:rtl"> דגירה התאים עבור 3-5 דק &#39;בחממה על מנת לאפשר העברת צבע דרך צמתים פער. הערה: ההכללה של סרום dialysed בשלב זה מסייעת סגירה נקבובית. </li><li style=";text-align:right;direction:rtl"> שטוף את הצבע מאוגדים עם ללא DMEM סידן להתבוננות תא חי. לחלופין, ניתן לתקן תאים בשלב זה, באמצעות התוספת של פורמלין 4% לטובים, ואז שטף עם PBS (פוספט שנאגרו מלוח). בכל המקרים הכביסה חייבת להסיר את כל הרקע. הערה: בניסויים ראשוניים כדי לקבוע את התנאים אופטימליים, אם המתח נמוך מדי, אז זה אפשרי לתת לתאים להתאושש בincubator לכמה דקות וelectroporate אותה השקופית פעם שנייה, כדי להציל את בעלות של שקופיות. </li></ol> .3 מיקרוסקופי בדיקה <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> שים לב לתאים תחת תאורת הקרינה, שימוש במיקרוסקופ הפוך מצויד במסנן המתאים לצבע בשימוש. לוציפר הצהוב, עירור הוא 423nm, 555nm פליטה, מסנן WBV למיקרוסקופ Nikon IX70. </li><li style=";text-align:right;direction:rtl"> לחסל את השפעות המניסקוס על ידי הצבת כיסוי להחליק זכוכית על גבי הפלסטיק היטב, לאחר המילוי אותו לחלק העליון עם נוזל, לבחון מורפולוגיה של תאים תחת ניגוד שלב. לתמונות טובות יותר, גם יכול להיות מנותק מהשקופית, וcoverslip מונח על המסגרת. לתאים קבועים, גם יכול להיות מלא עם גליצרול להסתכלות מיקרוסקופית, ואילו לתאים חיים הוא חייב להיות מלא במדיום גידול. הערה: כביסה וצילום הוא קלה יותר אם התאים קבועים עם פורמלדהיד בעקבות ההעברה של הצבע (שלב 2.7 לעיל). אם התאים לאt קבוע, הקרינה מסולקת מהתאים בתוך כ 60 דקות בהתאם לסוג התא, המתח וכמות LY הציג ואילו בתאים קבועים הקרינה נשמרת למשך מספר שעות. עם זאת, הקרינה דועכת או מתפוגגת לאחר הדגירה O / N, אפילו בתאים קבועים. מסיבה זו, צילומים חייבים להיות מצולמים בקרוב לאחר electroporation (איור 2). </li></ol> .4 Quantitation של תקשורת בין תאית <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> לצלם את התאים עם מטרת 20x תחת הקרינה וניגוד שלב (איור 3). </li><li style=";text-align:right;direction:rtl"> לזהות ולסמן בכוכב את תאי electroporated בגבול עם האזור-electroporated שאינו (איור 2, חץ, קצה electroporation). </li><li style=";text-align:right;direction:rtl"> (איורים 3 א ו 3 ב) לזהות ולסמן עם נקודת תאי fluorescing בצד הלא electroporated, שבו הצבע העביר דרך צמתים פער. </li><li style=";text-align:right;direction:rtl"> מחלקים את המספר הכולל שלfluorescing תאים באזור-electroporated שאינו במספר תאי electroporated לאורך הקצה (איורים 3 א ו 3 ב). הערה: ההעברה מלפחות 200 תאי גבול electroporated רציפים מחושבת עבור כל ניסוי. המספר שהתקבל הוא ערך GJIC. </li></ol>

<ol>
	<li>Raptis, L., 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=Electroporation+of+Adherent+Cells+in+Situ+for+the+Study+of+Signal+Transduction+and+Gap+Junctional+Communication.">Electroporation of Adherent Cells in Situ for the Study of Signal Transduction and Gap Junctional Communication.</a> Electroporation protocols. , 167-183 (2008).</li><li>Giorgetti-Peraldi, S., Ottinger, E., Wolf, G., Ye, B., Burke, T. R., Shoelson, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+effects+of+phosphotyrosine-binding+domain+inhibitors+on+insulin+receptor+signalling+and+trafficking.">Cellular effects of phosphotyrosine-binding domain inhibitors on insulin receptor signalling and trafficking.</a> Mol Cell Biol. 17, 1180-1188 (1997).</li><li>Boccaccio, C., Ando, M., Tamagnone, L., Bardelli, A., Michielli, P., Battistini, C., Comoglio, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+of+epithelial+tubules+by+growth+factor+HGF+depends+on+the+STAT+pathway.">Induction of epithelial tubules by growth factor HGF depends on the STAT pathway.</a> Nature. 391, 285-288 (1998).</li><li>Bardelli, A., Longati, P., Gramaglia, D., Basilico, C., Tamagnone, L., Giordano, S., Ballinari, D., Michieli, P., Comoglio, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Uncoupling+signal+transducers+from+oncogenic+MET+mutants+abrogates+cell+transformation+and+inhibits+invasive+growth.">Uncoupling signal transducers from oncogenic MET mutants abrogates cell transformation and inhibits invasive growth.</a> Proc Nat Acad Sci USA. 95, 14379-14383 (1998).</li><li>Gambarotta, G., Boccaccio, C., Giordano, S., Ando, M., Stella, M. C., Comoglio, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ets+up-regulates+met+transcription.">Ets up-regulates met transcription.</a> Oncogene. 13, 1911-1917 (1996).</li><li>Arulanandam, R., Vultur, A., Raptis, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transfection+techniques+affecting+Stat3+activity+levels.">Transfection techniques affecting Stat3 activity levels.</a> Anal Biochem. 338 (1), 83-89 (2005).</li><li>Boussiotis, V. A., Freeman, G. J., Berezovskaya, A., Barber, D. L., Nadler, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Maintenance+of+human+T+cell+anergy:+blocking+of+IL-2+gene+transcription+by+activated+Rap1.">Maintenance of human T cell anergy: blocking of IL-2 gene transcription by activated Rap1.</a> Science. 278 (5335), 124-128 (1997).</li><li>Brownell, H. L., Firth, K. L., Kawauchi, K., Delovitch, T. L., Raptis, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+technique+for+the+study+of+Ras+activation;+electroporation+of+[alpha-32]GTP.">A novel technique for the study of Ras activation; electroporation of [alpha-32]GTP.</a> DNA Cell Biol. 16, 103-110 (1997).</li><li>Tomai, E., Vultur, A., Balboa, V., Hsu, T., Brownell, H. L., Firth, K. L., Raptis, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+electroporation+of+radioactive+compounds+into+adherent+cells.">In situ electroporation of radioactive compounds into adherent cells.</a> DNA Cell Biol. 22, 339-346 (2003).</li><li>Raptis, L., Vultur, A., Tomai, E., Brownell, H. L., Firth, K. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+electroporation+of+radioactive+nucleotides:+assessment+of+Ras+activity+and+32P-labelling+of+cellular+proteins.">In situ electroporation of radioactive nucleotides: assessment of Ras activity and 32P-labelling of cellular proteins.</a> Cell Biology A Laboratory Handbook, Celis, Ed. 43, 329-339 (2006).</li><li>Nakashima, N., Rose, D., Xiao, S., Egawa, K., Martin, S., Haruta, T., Saltiel, A. R., Olefsky, 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=The+functional+role+of+crk+II+in+actin+cytoskeleton+organization+and+mitogenesis.">The functional role of crk II in actin cytoskeleton organization and mitogenesis.</a> J Biol Chem. 274, 3001-3008 (1999).</li><li>Raptis, L., Firth, K. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electroporation+of+adherent+cells+in+situ.">Electroporation of adherent cells in situ.</a> DNA Cell Biol. 9, 615-621 (1990).</li><li>Marais, R., Spooner, R. A., Stribbling, S. M., Light, Y., Martin, J., Springer, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+cell+surface+tethered+enzyme+improves+efficiency+in+gene-directed+enzyme+prodrug+therapy.">A cell surface tethered enzyme improves efficiency in gene-directed enzyme prodrug therapy.</a> Nat Biotechnol. 15, 1373-1377 (1997).</li><li>Nielsen, M. S., Nygaard, A. L., Sorgen, P. L., Verma, V., Delmar, M., Holstein-Rathlou, N. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gap+junctions.">Gap junctions.</a> Compr Physiol. 2 (3), 1981-2035 (2012).</li><li>Geletu, M., Trotman-Grant, A., Raptis, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mind+the+gap;+regulation+of+gap+junctional,+intercellular+communication+by+the+SRC+oncogene+product+and+its+effectors.">Mind the gap; regulation of gap junctional, intercellular communication by the SRC oncogene product and its effectors.</a> Anticancer Res. 32 (10), 4245-4250 (2012).</li><li>Vinken, M., Vanhaecke, T., Papeleu, P., Snykers, S., Henkens, T., Rogiers, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Connexins+and+their+channels+in+cell+growth+and+cell+death.">Connexins and their channels in cell growth and cell death.</a> Cell Signal. 18 (5), 592-600 (2006).</li><li>Fouly, M. H., Trosko, J. E., Chang, C. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Scrape-loading+and+dye+transfer:+A+rapid+and+simple+technique+to+study+gap+junctional+intercellular+communication.">Scrape-loading and dye transfer: A rapid and simple technique to study gap junctional intercellular communication.</a> Exp Cell Res. 168, 430-442 (1987).</li><li>Raptis, L., Brownell, H. L., Firth, K. L., MacKenzie, L. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+technique+for+the+study+of+intercellular,+junctional+communication;+electroporation+of+adherent+cells+on+a+partly+conductive+slide.">A novel technique for the study of intercellular, junctional communication; electroporation of adherent cells on a partly conductive slide.</a> DNA &amp; Cell Biol. 13, 963-975 (1994).</li><li>Anagnostopoulou, A., Cao, J., Vultur, A., Firth, K. L., Raptis, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Examination+of+gap+junctional,+intercellular+communication+by+in+situ+electroporation+on+two+co-planar+indium-tin+oxide+electrodes.">Examination of gap junctional, intercellular communication by in situ electroporation on two co-planar indium-tin oxide electrodes.</a> Mol Oncol. 1, 226-231 (2007).</li><li>Tomai, E., Brownell, H. L., Tufescu, T., Reid, K., Raptis, S., Campling, B. G., Raptis, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+functional+assay+for+intercellular,+junctional+communication+in+cultured+human+lung+carcinoma+cells.">A functional assay for intercellular, junctional communication in cultured human lung carcinoma cells.</a> Lab Invest. 78, 639-640 (1998).</li><li>Tomai, E., Brownell, H. L., Tufescu, T., Reid, K., Raptis, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gap+junctional+communication+in+lung+carcinoma+cells.">Gap junctional communication in lung carcinoma cells.</a> Lung Cancer. 23, 223-231 (1999).</li><li>Geletu, M., Chaize, C., Arulanandam, R., Vultur, A., Kowolik, C., Anagnostopoulou, A., Jove, R., Raptis, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stat3+activity+is+required+for+gap+junctional+permeability+in+normal+epithelial+cells+and+fibroblasts.">Stat3 activity is required for gap junctional permeability in normal epithelial cells and fibroblasts.</a> DNA Cell Biol. 28, 319-327 (2009).</li><li>Geletu, M., Arulanandam, R., Greer, S., Trotman-Grant, A., Tomai, E., Raptis, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stat3+is+a+positive+regulator+of+gap+junctional+intercellular+communication+in+cultured,+human+lung+carcinoma+cells.">Stat3 is a positive regulator of gap junctional intercellular communication in cultured, human lung carcinoma cells.</a> BMC Cancer. 12, 605 (2012).</li><li>Brownell, H. L., Narsimhan, R., Corbley, M. J., Mann, V. M., Whitfield, J. F., Raptis, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ras+is+involved+in+gap+junction+closure+in+mouse+fibroblasts+or+preadipocytes+but+not+in+differentiated+adipocytes.">Ras is involved in gap junction closure in mouse fibroblasts or preadipocytes but not in differentiated adipocytes.</a> DNA &amp; Cell Biol. 15, 443-451 (1996).</li><li>Weber, P. A., Chang, H. C., Spaeth, K. E., Nitsche, J. M., Nicholson, B. 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+permeability+of+gap+junction+channels+to+probes+of+different+size+is+dependent+on+connexin+composition+and+permeant-pore+affinities.">The permeability of gap junction channels to probes of different size is dependent on connexin composition and permeant-pore affinities.</a> Biophys J. 87 (2), 958-973 (2004).</li><li>Graham, F. L., vander Eb, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+technique+for+the+assay+of+infectivity+of+human+Adenovirus+5+DNA.">A new technique for the assay of infectivity of human Adenovirus 5 DNA.</a> Virology. 52, 456-467 (1973).</li><li>Arulanandam, R., Vultur, A., Cao, J., Carefoot, E., Truesdell, P., Elliott, B., Larue, L., Feracci, H., Raptis, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cadherin-cadherin+engagement+promotes+survival+via+Rac/Cdc42+and+Stat3.">Cadherin-cadherin engagement promotes survival via Rac/Cdc42 and Stat3.</a> Mol Cancer Res 7. , 1310-1327 (2009).</li><li>Williams, E. J., Dunican, D. J., Green, P. J., Howell, F. V., Derossi, D., Walsh, F. S., Doherty, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+inhibition+of+growth+factor-stimulated+mitogenesis+by+a+cell-permeable+Grb2-binding+peptide.">Selective inhibition of growth factor-stimulated mitogenesis by a cell-permeable Grb2-binding peptide.</a> J. Biol. Chem. 272, 22349-22354 (1997).</li><li>Raptis, L., Brownell, H. L., Vultur, A. M., Ross, G., Tremblay, E., Elliott, B. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Specific+inhibition+of+Growth+Factor-stimulated+ERK1/2+activation+in+intact+cells+by+electroporation+of+a+Grb2-SH2+binding+peptide.">Specific inhibition of Growth Factor-stimulated ERK1/2 activation in intact cells by electroporation of a Grb2-SH2 binding peptide.</a> Cell Growth Differ. 11, 293-303 (2000).</li><li>Meda, P. <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+molecular+permeability+of+connexin+channels.">Assaying the molecular permeability of connexin channels.</a> Methods Mol Biol. 154, 201-224 (2001).</li><li>Hofgaard, J. P., Mollerup, S., Holstein-Rathlou, N. H., Nielsen, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantification+of+gap+junctional+intercellular+communication+based+on+digital+image+analysis.">Quantification of gap junctional intercellular communication based on digital image analysis.</a> Am J Physiol Regul Integr Comp Physiol. 297 (2), R243-R247 (2009).</li><li>Raptis, L., Lamfrom, H., Benjamin, T. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+cellular+phenotype+and+expression+of+polyomavirus+middle+T+antigen+in+rat+fibroblasts.">Regulation of cellular phenotype and expression of polyomavirus middle T antigen in rat fibroblasts.</a> Mol Cell Biol. 5, 2476-2486 (1985).</li><li>Raptis, L., Marcellus, R. C., Whitfield, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+membrane-associated+protein+kinase+C+activity+correlates+to+tumorigenicity+but+not+anchorage-independence+in+a+clone+of+mouse+NIH+3T3+cells.">High membrane-associated protein kinase C activity correlates to tumorigenicity but not anchorage-independence in a clone of mouse NIH 3T3 cells.</a> Exp Cell Res. 207, 152-154 (1993).</li><li>Vultur, A., Cao, J., Arulanandam, R., Turkson, J., Jove, R., Greer, P., Craig, A., Elliott, B. E., Raptis, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell+to+cell+adhesion+modulates+Stat3+activity+in+normal+and+breast+carcinoma+cells.">Cell to cell adhesion modulates Stat3 activity in normal and breast carcinoma cells.</a> Oncogene. 23, 2600-2616 (2004).</li><li>Vultur, A., Arulanandam, R., Turkson, J., Niu, G., Jove, R., Raptis, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stat3+is+required+for+full+neoplastic+transformation+by+the+Simian+Virus+40+Large+Tumor+antigen.">Stat3 is required for full neoplastic transformation by the Simian Virus 40 Large Tumor antigen.</a> Mol Biol Cell. 16, 3832-3846 (2005).</li></ol>

The corresponding author is the inventor in a patent held by Queen&#8217;s University, which has been licensed to Cell Projects Inc. The company or the University had no influence upon the contents of the paper.

שלבים קריטיים בפרוטוקול חומר Electroporated טוהר של החומר המיועד לelectroporated הוא מאוד חשוב. אם התאים מאוד שטוחים, ריכוזים אז גבוהים יותר של צבע המעקב חייבים להיות בשימוש (עד 20 מ&quot;ג / מ&quot;ל לLY) ובמקרים כאלה, טוהר חשוב עוד יותר מא?...

היישום של זרם חשמלי לתא גורם להיווצרות של נקבוביות על קרום התא, על ידי electroporation תהליך המכונה. הנקבוביות לאפשר המעבר של מגוון רחב של מולקולות nonpermeant דרך הממברנה. השדה החשמלי ניתן לשלוט במדויק, כך שנקבובי שנוצרו הם קטנים מאוד וreclose במהירות, עם הפרעה מינימאלית לפיסיולוגיה התאית. מעניין, ניתן לגדל תאים חסיד בשקופית זכוכית מצופה בתחמוצת מוליך ושקופה אינדיום פח (איטו) וelectroporated באתר, שעל פני השטח שבו הם גדלים, ללא ניתוק להיות electroporated בהשעיה. תאים יכולים לגדול היטב על פני השטח זה, וכפי שהם מחוברים והאריכו, התצפית מיקרוסקופית מפורטת אפשרית. שימוש בטכניקה זו, יכולה להיות הציגו מולקולות nonpermeant קטנות באופן מיידי ולמהות 100% מהתאים, מה שהופך את הטכניקה זו מתאימה במיוחד למחקרים על ההפעלה של components של מסלול בעקבות הגירוי ליגנד של קולט (שנסקר ב1). Electroporation כבר בשימוש בעיקר עבור כניסתה של DNA (electrotransfection המכונה גם). עם זאת, electroporation באתר יכול להיות בעל ערך עבור כניסתה של מגוון רחב של מולקולות, כגון פפטידים 2-4, oligonucleotides, כגון RNA antisense, oligonucleotides פעמיים תקועים דמה DNA לעכב גורם שעתוק מחייב, או siRNA 3,5, 6 נוקלאוטידים, רדיואקטיבי 7-10, חלבוני 11 12 או בעד סמים 13. בעקבות electroporation, ניתן lysed תאים עבור ניתוחים ביוכימיים או קבוע ומוכתם עם נוגדנים. ציפוי איטו המוליך הוא דק מאוד, 800-1,000Å, כך שצמיחת תאים אינה מופרעת על ידי ההבדל בגובה של שני משטחים, כתאים לגדול מעבר לקצה של ציפוי המוליך. זו מציעה את היתרון שאינו electropניתן לגדל תאים נאמו לצד אלה electroporated, שישמשו כבקרה. אותה הגישה יכולה לשמש לבחינת הפער junctional, תקשורת בין תאית (GJIC), כפי שמתוארת בווידאו. צמתים פער הם ערוצים המחברים את הפנים של תאים סמוכים 14. פער junctional, תקשורת בין תאית משחקת תפקיד חשוב בהיווצרות גידולים וגרור, ואילו אונקוגנים כגון Src לדכא GJIC 15,16. כדי לבחון GJIC צבע ניאון כגון צהוב לוציפר (LY) הוא הציג לעתים קרובות לתוך תאים בתרבית באמצעות microinjection או לגרד טעינה 17 ודיפוזיה של הצבע לתוך תאים שכנים הוא ציינה מיקרוסקופי תחת תאורת פלואורסצנטי. טכניקות אלו אולם תמיד לגרום נזק לתאים. עכשיו אנו מתארים טכניקה שבה תאים גדלים בשקופית זכוכית שמצופית בחלקו עם איטו 18. דופק חשמלי היה מוחל בנוכחות LY (או צבעים אחרים) caבאמצעות החדירה שלה לתאי גידול בחלק המוליך של השקופית, ואילו הגירת צבע לתאים הסמוכים, שאינו electroporated נצפתה מיקרוסקופית באמצעות תאורת פלואורסצנטי. כדי להימנע מתאים רגישים מטרידים שעשויות נוטים להתנתק מmonolayer, הרכבה תוכננה שלא דורשת אלקטרודה שממוקמת על גבי התאים ליישם את 19 הזרם החשמלי. גישה זו מציעה את היכולת לכמת GJIC במספר גדול של תאים, ללא כל הפרעה לגילוי לחילוף חומרים תאיים, כפי שצוינה על ידי בהעדר השפעה על אורכו של שלב G1 בעקבות גירוי סרום 12, להגדיל ברמות של FOS חלבון protooncogene (Raptis, לא פורסם) או שני קינאז הקשורים ללחץ סלולארי, חזיר p38 או JNK / SAPK קינאז 1. גישה זו התאפשרה הבדיקה של הקשר בין רמות ביטוי אונקוגן, השינוי וGJ18 IC, כמו גם את ההשפעה של Src וSTAT3 על GJIC במגוון רחב של סוגי תאים, כולל תאים טריים תרבותיים מדגימות גידול ריאות 20-23. בנוסף, באתרו electroporation עם ההתקנה תוארה שאין בו אלקטרודה עליונה כבר מועסק בהצלחה להפגנה של סגירת צומת פער על בידול adipocytic, למרות שקובץ מצורף סלולארי למצע מצטמצם בשלב ש19,24.

<table><tbody><tr><td>DMEM</td><td>Cellgro http://www.cellgro.com/</td><td>50-013-PB</td><td></td></tr><tr><td>DMEM without Calcium</td><td>Hyclone (Thermo scientific: http://www.thermoscientific.com)</td><td>SH30319-01</td><td></td></tr><tr><td>Donor Calf Serum&amp;nbsp;</td><td>PAA: http://www.paa.com/</td><td>Cat.# B15-008</td><td></td></tr><tr><td>Fetal Bovine Serum</td><td>PAA: http://www.paa.com/</td><td>Cat.# A15-751</td><td></td></tr><tr><td>Electroporation apparatus</td><td>Cell Projects Ltd UK: http://www.cellprojects.com/</td><td>ACE-100</td><td></td></tr><tr><td>Chambers</td><td>Cell Projects Ltd UK</td><td>ACE-04-CC</td><td>4-wells</td></tr><tr><td>Chambers</td><td>Cell Projects Ltd UK</td><td>ACE-08-CC</td><td>8-wells</td></tr><tr><td>Lucifer Yellow</td><td>Cell Projects Ltd UK</td><td>ACE-25-LY</td><td>High purity</td></tr><tr><td>CelTak</td><td>BD Biosciences</td><td>354240</td><td>Cell and tissue adhesive</td></tr><tr><td>Fibronectin</td><td>Sigma Aldrich</td><td>F1141</td><td></td></tr><tr><td>Collagen</td><td>BD Biosciences</td><td>354236</td><td></td></tr><tr><td>Poly-Lysine</td><td>Sigma Aldrich</td><td>P8920</td><td></td></tr></tbody></table>

a functional assay for gap junctional examination; electroporation of adherent cells on indium-tin oxide

In this technique, cells are cultured on a glass slide that is partly coated with indium-tin oxide (ITO), a transparent, electrically conductive material. A variety of molecules, such as peptides or oligonucleotides can be introduced into essentially 100% of the cells in a non-traumatic manner.&#160; Here, we describe how it can be used to study intercellular, gap junctional communication. Lucifer yellow penetrates into the cells when an electric pulse, applied to the conductive surface on which they are growing, causes pores to form through the cell membrane. This is electroporation. Cells growing on the nonconductive&#160;glass surface immediately adjacent to the electroporated region do not take up Lucifer yellow by electroporation but do acquire the fluorescent dye as it is passed to them via gap junctions that link them to the electroporated cells. The results of the transfer of dye from cell to cell can be observed microscopically under fluorescence illumination. This technique allows for precise quantitation of gap junctional communication. In addition, it can be used for the introduction of peptides or other non-permeant molecules, and the transfer of small electroporated peptides via gap junctions to inhibit the signal in the adjacent, non-electroporated cells is a powerful demonstration of signal inhibition.

איור 2 מראה תאי כבד החולדה T51B אפיתל 22, electroporated עם LY וצילמו מתחת לקרינה (פנל וארוחת בוקר), או שלב בניגוד תאורה (C), הבאים קיבעון וכביסה. בפנל, בקצה אזור electroporated מסומן באדום. השיפוע של הקרינה בצד הימין של הקו האדום מציין העברה דרך צמתים פער. באיור 3 א ו...

Watch this Scientific Journal Video about A Functional Assay for Gap Junctional Examination; Electroporation of Adherent Cells on Indium-Tin Oxide at JoVE.com

A Functional Assay for Gap Junctional Examination; Electroporation of Adherent Cells on Indium-Tin Oxide

This presentation demonstrates a method whereby electroporation of adherent, cultured cells is used for the study of intercellular, junctional communication, while the cells grow on a slide coated with conductive and transparent indium-tin oxide.

Assay פונקציונלי לגאפ junctional בחינה; Electroporation של תאים חסידים על אינדיום הבדיל-אוקסיד

In this technique, cells are cultured on a glass slide that is partly coated with indium-tin oxide (ITO), a transparent, electrically conductive material. ...

a-functional-assay-for-gap-junctional-examination-electroporation

Research

JoVE Journal

Biology

9.9K Views.  Queen's University. This presentation demonstrates a method whereby electroporation of adherent, cultured cells is used for the study of intercellular, junctional communication, while the cells grow on a slide coated with conductive and transparent indium-tin oxide.

Video: A Functional Assay for Gap Junctional Examination; Electroporation of Adherent Cells on Indium-Tin Oxide

A Mimic of the Tumor Microenvironment: A Simple Method for Generating Enriched Cell Populations and Investigating Intercellular Communication

Understanding the early heterotypic interactions between cancer cells and the surrounding non-cancerous stroma is important in elucidating the events leading to stromal activation and establishment of the tumor microenvironment (TME). Several in vitro and in vivo models of the TME have been developed; however, in general these models do not readily permit isolation of individual cell populations, under non-perturbing conditions, for further study. To circumvent this difficulty, we have employed an in vitro TME model using a cell growth substrate consisting of a permeable microporous membrane insert that permits simple generation of highly enriched cell populations grown intimately, yet separately, on either side of the insert&#39;s membrane for extended co-culture times. Through use of this model, we are capable of generating greatly enriched cancer-associated fibroblast (CAF) populations from normal diploid human fibroblasts following co-culture (120 hr) with highly metastatic human breast carcinoma cells, without the use of fluorescent tagging and/or cell sorting. Additionally, by modulating the pore-size of the insert, we can control for the mode of intercellular communication (e.g., gap-junction communication, secreted factors) between the two heterotypic cell populations, which permits investigation of the mechanisms underlying the development of the TME, including the role of gap-junction permeability. This model serves as a valuable tool in enhancing our understanding of the initial events leading to cancer-stroma initiation, the early evolution of the TME, and the modulating effect of the stroma on the responses of cancer cells to therapeutic agents.

We adapted a permeable microporous membrane insert to mimic the tumor microenvironment (TME). The model consists of a mixed cell culture, allows simplified generation of highly enriched individual cell populations without using fluorescent tagging or cell sorting, and permits studying intercellular communication within the TME under normal or stress conditions.

חקיין של microenvironment הגידול: שיטה פשוטה ליצירת אוכלוסיות תאים מועשרות חוקרים אינטר תקשורת

Understanding the early heterotypic interactions between cancer cells and the surrounding non-cancerous stroma is important in elucidating the events ...

Cancer Research

Adhesion Frequency Assay for In Situ Kinetics Analysis of Cross-Junctional Molecular Interactions at the Cell-Cell Interface

The micropipette adhesion assay was developed in 1998 to measure two-dimensional (2D) receptor-ligand binding kinetics1. The assay uses a human red blood cell (RBC) as adhesion sensor and presenting cell for one of the interacting molecules. It employs micromanipulation to bring the RBC into contact with another cell that expresses the other interacting molecule with precisely controlled area and time to enable bond formation. The adhesion event is detected as RBC elongation upon pulling the two cells apart. By controlling the density of the ligands immobilized on the RBC surface, the probability of adhesion is kept in mid-range between 0 and 1. The adhesion probability is estimated from the frequency of adhesion events in a sequence of repeated contact cycles between the two cells for a given contact time. Varying the contact time generates a binding curve. Fitting a probabilistic model for receptor-ligand reaction kinetics1 to the binding curve returns the 2D affinity and off-rate.
The assay has been validated using interactions of Fc&gamma; receptors with IgG Fc1-6, selectins with glycoconjugate ligands6-9, integrins with ligands10-13, homotypical cadherin binding14, T cell receptor and coreceptor with peptide-major histocompatibility complexes15-19.
The method has been used to quantify regulations of 2D kinetics by biophysical factors, such as the membrane microtopology5, membrane anchor2, molecular orientation and length6, carrier stiffness9, curvature20, and impingement force20, as well as biochemical factors, such as modulators of the cytoskeleton and membrane microenvironment where the interacting molecules reside and the surface organization of these molecules15,17,19.
The method has also been used to study the concurrent binding of dual receptor-ligand species3,4, and trimolecular interactions19 using a modified model21.
The major advantage of the method is that it allows study of receptors in their native membrane environment. The results could be very different from those obtained using purified receptors17. It also allows study of the receptor-ligand interactions in a sub-second timescale with temporal resolution well beyond the typical biochemical methods.
To illustrate the micropipette adhesion frequency method, we show kinetics measurement of intercellular adhesion molecule 1 (ICAM-1) functionalized on RBCs binding to integrin &alpha;L&beta;2 on neutrophils with dimeric E-selectin in the solution to activate &alpha;L&beta;2.

Adhesion Frequency Assay for In Situ Kinetics Analysis of Cross-Junctional Molecular Interactions at the Cell-Cell Interface

An adhesion frequency assay for measuring receptor-ligand interaction kinetics when both molecules are anchored on the surfaces of the interacting cells is described. This mechanically-based assay is exemplified using a micropipette-pressurized human red blood cell as adhesion sensor and integrin &alpha;L&beta;2 and intercellular adhesion molecule-1 as interacting receptors and ligands.

תדירות הדבקה Assay עבור באתרו קינטיקס ניתוח חוצה Junctional אינטראקציות מולקולריות על ממשק Cell-Cell

The micropipette adhesion assay was developed in 1998 to measure two-dimensional (2D) receptor-ligand binding kinetics1. The assay uses a human red blood ...

Bioengineering

Development of an In Vitro Assay to Evaluate Contractile Function of Mesenchymal Cells that Underwent Epithelial-Mesenchymal Transition

Fibrosis is often involved in the pathogenesis of various chronic progressive diseases such as interstitial pulmonary disease. Pathological hallmark is the formation of fibroblastic foci, which is associated with the disease severity. Mesenchymal cells consisting of the fibroblastic foci are proposed to be derived from several cell sources, including originally resident intrapulmonary fibroblasts and circulating fibrocytes from bone marrow. Recently, mesenchymal cells that underwent epithelial-mesenchymal transition (EMT) have been also supposed to contribute to the pathogenesis of fibrosis. In addition, EMT can be induced by transforming growth factor &#946;, and EMT can be enhanced by pro-inflammatory cytokines like tumor necrosis factor &#945;. The gel contraction assay is an ideal in vitro model for the evaluation of contractility, which is one of the characteristic functions of fibroblasts and contributes to wound repair and fibrosis. Here, the development of a gel contraction assay is demonstrated for evaluating contractile ability of mesenchymal cells that underwent EMT.

Development of an In Vitro Assay to Evaluate Contractile Function of Mesenchymal Cells that Underwent Epithelial-Mesenchymal Transition

Here, we describe the development and application of a gel contraction assay for evaluating contractile function in mesenchymal cells that underwent epithelial-mesenchymal transition.

פיתוח של<em&gt; במבחנה</em&gt; Assay לאבחון תפקוד התכווצות של תאי mesenchymal שעבר אפיתל-mesenchymal מעבר

Fibrosis is often involved in the pathogenesis of various chronic progressive diseases such as interstitial pulmonary disease. Pathological hallmark is ...

Developmental Biology

Electric Cell-substrate Impedance Sensing for the Quantification of Endothelial Proliferation, Barrier Function, and Motility

Electric Cell-substrate Impedance Sensing (ECIS) is an in vitro impedance measuring system to quantify the behavior of cells within adherent cell layers. To this end, cells are grown in special culture chambers on top of opposing, circular gold electrodes. A constant small alternating current is applied between the electrodes and the potential across is measured. The insulating properties of the cell membrane create a resistance towards the electrical current flow resulting in an increased electrical potential between the electrodes. Measuring cellular impedance in this manner allows the automated study of cell attachment, growth, morphology, function, and motility. Although the ECIS measurement itself is straightforward and easy to learn, the underlying theory is complex and selection of the right settings and correct analysis and interpretation of the data is not self-evident. Yet, a clear protocol describing the individual steps from the experimental design to preparation, realization, and analysis of the experiment is not available. In this article the basic measurement principle as well as possible applications, experimental considerations, advantages and limitations of the ECIS system are discussed. A guide is provided for the study of cell attachment, spreading and proliferation; quantification of cell behavior in a confluent layer, with regard to barrier function, cell motility, quality of cell-cell and cell-substrate adhesions; and quantification of wound healing and cellular responses to vasoactive stimuli. Representative results are discussed based on human microvascular (MVEC) and human umbilical vein endothelial cells (HUVEC), but are applicable to all adherent growing cells.

This protocol reviews Electric Cell-substrate Impedance Sensing, a method to record and analyze the impedance spectrum of adherent cells for the quantification of cell attachment, proliferation, motility, and cellular responses to pharmacological and toxic stimuli. Detection of endothelial permeability and assessment of cell-cell and cell-substrate contacts are emphasized.

חשמל Cell-מצע עכבת חישה לכימות של האנדותל למניעת הפצת נשק, תפקוד מחסום, ותנועתיות

Electric Cell-substrate Impedance Sensing (ECIS) is an in vitro impedance measuring system to quantify the behavior of cells within adherent cell layers. ...

A Galvanotaxis Assay for Analysis of Neural Precursor Cell Migration Kinetics in an Externally Applied Direct Current Electric Field

The discovery of neural stem and progenitor cells (collectively termed neural precursor cells) (NPCs) in the adult mammalian brain has led to a body of research aimed at utilizing the multipotent and proliferative properties of these cells for the development of neuroregenerative strategies. A critical step for the success of such strategies is the mobilization of NPCs toward a lesion site following exogenous transplantation or to enhance the response of the endogenous precursors that are found in the periventricular region of the CNS. Accordingly, it is essential to understand the mechanisms that promote, guide, and enhance NPC migration. Our work focuses on the utilization of direct current electric fields (dcEFs) to promote and direct NPC migration - a phenomenon known as galvanotaxis. Endogenous physiological electric fields function as critical cues for cell migration during normal development and wound repair. Pharmacological disruption of the trans-neural tube potential in axolotl embryos causes severe developmental malformations1. In the context of wound healing, the rate of repair of wounded cornea is directly correlated with the magnitude of the epithelial wound potential that arises after injury, as shown by pharmacological enhancement or disruption of this dcEF2-3. We have demonstrated that adult subependymal NPCs undergo rapid and directed cathodal migration in vitro when exposed to an externally applied dcEF. In this protocol we describe our lab's techniques for creating a simple and effective galvanotaxis assay for high-resolution, long-term observation of directed cell body translocation (migration) on a single-cell level. This assay would be suitable for investigating the mechanisms that regulate dcEF transduction into cellular motility through the use of transgenic or knockout mice, short interfering RNA, or specific receptor agonists/antagonists.

In this protocol we demonstrate how to construct custom chambers that permit the application of a direct current electric field to enable time-lapse imaging of adult brain derived neural precursor cell translocation during galvanotaxis.

Assay Galvanotaxis לניתוח של קינטיקס נדידת תאים העצביים המבשר בשדה חשמלי נוכחי לשימוש חיצוני ישיר

The discovery of neural stem and progenitor  cells (collectively termed neural precursor cells) (NPCs) in the adult  mammalian brain has led to a body of ...

Neuroscience

Mutagenesis and Functional Analysis of Ion Channels Heterologously Expressed in Mammalian Cells

We will demonstrate how to study the functional effects of introducing a point mutation in an ion channel. We study G protein-gated inwardly rectifying potassium (referred to as GIRK) channels, which are important for regulating the excitability of neurons. There are four different mammalian GIRK channel subunits (GIRK1-GIRK4) - we focus on GIRK2 because it forms a homotetramer. Stimulation of different types of G protein-coupled receptors (GPCRs), such as the muscarinic receptor (M2R), leads to activation of GIRK channels. Alcohol also directly activates GIRK channels. We will show how to mutate one amino acid by specifically changing one or more nucleotides in the cDNA for the GIRK channel. This mutated cDNA sequence will be amplified in bacteria, purified, and the presence of the point mutation will be confirmed by DNA sequencing. The cDNAs for the mutated and wild-type GIRK channels will be transfected into human embryonic kidney HEK293T cells cultured in vitro. Lastly, whole-cell patch-clamp electrophysiology will be used to study the macroscopic potassium currents through the ectopically expressed wild-type or mutated GIRK channels. In this experiment, we will examine the effect of a L257W mutation in GIRK2 channels on M2R-dependent and alcohol-dependent activation.

We will demonstrate how to study the effect of a single point mutation on the function of an ion channel.

Mutagenesis וניתוח פונקציונלי של תעלות יונים הביעו Heterologously בתאי יונקים

We will demonstrate how to study the functional effects of introducing a point mutation in an ion channel. We study G protein-gated inwardly rectifying ...

Optimized Transfection Strategy for Expression and Electrophysiological Recording of Recombinant Voltage-Gated Ion Channels in HEK-293T Cells

The in vitro expression and electrophysiological recording of recombinant voltage-gated ion channels in cultured human embryonic kidney cells (HEK-293T) is a ubiquitous research strategy. HEK-293T cells must be plated onto glass coverslips at low enough density so that they are not in contact with each other in order to allow for electrophysiological recording without confounding effects due to contact with adjacent cells. Transfected channels must also express with high efficiency at the plasma membrane for whole-cell patch clamp recording of detectable currents above noise levels. Heterologous ion channels often require long incubation periods at 28&deg;C after transfection in order to achieve adequate membrane expression, but there are increasing losses of cell-coverslip adhesion and membrane stability at this temperature. To circumvent this problem, we developed an optimized strategy to transfect and plate HEK-293T cells. This method requires that cells be transfected at a relatively high confluency, and incubated at 28&deg;C for varying incubation periods post-transfection to allow for adequate ion channel protein expression. Transfected cells are then plated onto glass coverslips and incubated at 37&deg;C for several hours, which allows for rigid cell attachment to the coverslips and membrane restabilization. Cells can be recorded shortly after plating, or can be transferred to 28&deg;C for further incubation. We find that the initial incubation at 28&deg;C, after transfection but before plating, is key for the efficient expression of heterologous ion channels that normally do not express well at the plasma membrane. Positively transfected, cultured cells are identified by co-expressed eGFP or eGFP expressed from a bicistronic vector (e.g. pIRES2-EGFP) containing the recombinant ion channel cDNA just upstream of an internal ribosome entry site and an eGFP coding sequence. Whole-cell patch clamp recording requires specialized equipment, plus the crafting of polished recording electrodes and L-shaped ground electrodes from borosilicate glass. Drug delivery to study the pharmacology of ion channels can be achieved by directly micropipetting drugs into the recording dish, or by using microperfusion or gravity flow systems that produce uninterrupted streams of drug solution over recorded cells.

Reliable method for highly efficient in vitro expression and subsequent electrophysiological recording of recombinant voltage-gated ion channels in cultured human embryonic kidney cells (HEK-293T).

Transfection אסטרטגיה אופטימיזציה עבור הביטוי הקלטה של ​​אלקטרו Voltage-מגודרת ערוצי רקומביננטי יון ב HEK-293T תאים

The in vitro expression and electrophysiological recording of recombinant voltage-gated ion channels in cultured human embryonic kidney cells (HEK-293T) ...

Single-cell Microinjection for Cell Communication Analysis

Gap junctions are intercellular channels that allow the communication of neighboring cells. This communication depends on the contribution of a hemichannel by each neighboring cell to form the gap junction. In mammalian cells, the hemichannel is formed by six connexins, monomers with four transmembrane domains and a C and N terminal within the cytoplasm. Gap junctions permit the exchange of ions, second messengers, and small metabolites. In addition, they have important roles in many forms of cellular communication within physiological processes such as synaptic transmission, heart contraction, cell growth and differentiation. We detail how to perform a single-cell microinjection of Lucifer Yellow to visualize cellular communication via gap-junctions in living cells. It is expected that in functional gap junctions, the dye will diffuse from the loaded cell to the connected cells. It is a very useful technique to study gap junctions since you can evaluate the diffusion of the fluorescence in real time. We discuss how to prepare the cells and the micropipette, how to use a micromanipulator and inject a low molecular weight fluorescent dye in an epithelial cell line.

We describe here how to perform a single-cell microinjection of Lucifer Yellow to visualize cellular communication via gap-junctions in living cells, and provide some useful tips. We expect that this paper will help everyone to evaluate the degree of cellular coupling due to functional gap junctions. Everything described here could be, in principle, adapted to other fluorescent dyes with molecular weight below 1,000 Daltons.

Microinjection מתא בודד לניתוח תקשורת נייד

Gap junctions are intercellular channels that allow the communication of neighboring cells. This communication depends on the contribution of a ...

Gap Junctional Intercellular Communication: A Functional Biomarker to Assess Adverse Effects of Toxicants and Toxins, and Health Benefits of Natural Products

This protocol describes a scalpel loading-fluorescent dye transfer (SL-DT) technique that measures intercellular communication through gap junction channels, which is a major intercellular process by which tissue homeostasis is maintained. Interruption of gap junctional intercellular communication (GJIC) by toxicants, toxins, drugs, etc. has been linked to numerous adverse health effects. Many genetic-based human diseases have been linked to mutations in gap junction genes. The SL-DT technique is a simple functional assay for the simultaneous assessment of GJIC in a large population of cells. The assay involves pre-loading cells with a fluorescent dye by briefly perturbing the cell membrane with a scalpel blade through a population of cells. The fluorescent dye is then allowed to traverse through gap junction channels to neighboring cells for a designated time. The assay is then terminated by the addition of formalin to the cells. The spread of the fluorescent dye through a population of cells is assessed with an epifluorescence microscope and the images are analyzed with any number of morphometric software packages that are available, including free software packages found on the public domain. This assay has also been adapted for in vivo studies using tissue slices from various organs from treated animals. Overall, the SL-DT assay can serve a broad range of in vitro pharmacological and toxicological needs, and can be potentially adapted for high throughput set-up systems with automated fluorescence microscopy imaging and analysis to elucidate more samples in a shorter time.

This protocol describes a scalpel loading-fluorescent dye transfer technique that measures intercellular communication through gap junction channels. Gap junctional intercellular communication is a major cellular process by which tissue homeostasis is maintained and disruption of this cell signaling has adverse health effects.

גאפ junctional אינטר תקשורת: ביומרקר פונקציונלית להערכת תופעות לוואי של toxicants ורעלים, ואת היתרונות הבריאותיים של מוצרים טבעיים

This protocol describes a scalpel loading-fluorescent dye transfer (SL-DT) technique that measures intercellular communication through gap junction ...

An Iodide-Yellow Fluorescent Protein-Gap Junction-Intercellular Communication Assay

Gap junctions (GJs) are cell membrane channels that allow diffusion of molecules smaller than 1 kDa between adjacent cells. As they have physiological and pathological roles, there is need of high-throughput screening (HTS) assays to identify GJ modulators in drug discovery and toxicology assays. A novel iodide-yellow fluorescent protein-gap junction-intercellular communication (I-YFP-GJIC) assay fulfills this need. It is a cell-based assay including acceptor and donor cells that are engineered to stably express a yellow fluorescent protein (YFP) variant, whose fluorescence is sensitively quenched by iodide, or SLC26A4, an iodide transporter, respectively. When iodide is added to a mixed culture of the two cell types, they enter the donor cells via the SLC26A4 transporter and diffuse to the adjacent acceptor cells via GJs where they quench the YFP fluorescence. YFP fluorescence is measured well by well in a kinetic mode. The YFP quenching rate reflects GJ activity. The assay is reliable and rapid enough to be used for HTS. The protocol for the I-YFP-GJIC assay using the LN215 cells, human glioma cells, is described.

Here, we present a protocol for a novel gap junction intercellular communication assay designed for the high-throughput screening of gap junction-modulating chemicals for drug discovery and toxicological assessment.

Assay תקשורת צומת-המערכת יודיד-צהוב הניאון חלבון-Gap

Gap junctions (GJs) are cell membrane channels that allow diffusion of molecules smaller than 1 kDa between adjacent cells. As they have physiological and ...

Assay פונקציונלי לגאפ junctional בחינה; Electroporation של תאים חסידים על אינדיום הבדיל-אוקסיד

Summary

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חקיין של microenvironment הגידול: שיטה פשוטה ליצירת אוכלוסיות תאים מועשרות חוקרים אינטר תקשורת

תדירות הדבקה Assay עבור באתרו קינטיקס ניתוח חוצה Junctional אינטראקציות מולקולריות על ממשק Cell-Cell

פיתוח של

חשמל Cell-מצע עכבת חישה לכימות של האנדותל למניעת הפצת נשק, תפקוד מחסום, ותנועתיות

Assay Galvanotaxis לניתוח של קינטיקס נדידת תאים העצביים המבשר בשדה חשמלי נוכחי לשימוש חיצוני ישיר

Mutagenesis וניתוח פונקציונלי של תעלות יונים הביעו Heterologously בתאי יונקים

Transfection אסטרטגיה אופטימיזציה עבור הביטוי הקלטה של אלקטרו Voltage-מגודרת ערוצי רקומביננטי יון ב HEK-293T תאים

Microinjection מתא בודד לניתוח תקשורת נייד

גאפ junctional אינטר תקשורת: ביומרקר פונקציונלית להערכת תופעות לוואי של toxicants ורעלים, ואת היתרונות הבריאותיים של מוצרים טבעיים

Assay תקשורת צומת-המערכת יודיד-צהוב הניאון חלבון-Gap

Assay פונקציונלי לגאפ junctional בחינה; Electroporation של תאים חסידים על אינדיום הבדיל-אוקסיד

Summary

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Chapters in this video

חקיין של microenvironment הגידול: שיטה פשוטה ליצירת אוכלוסיות תאים מועשרות חוקרים אינטר תקשורת

תדירות הדבקה Assay עבור באתרו קינטיקס ניתוח חוצה Junctional אינטראקציות מולקולריות על ממשק Cell-Cell

פיתוח של

חשמל Cell-מצע עכבת חישה לכימות של האנדותל למניעת הפצת נשק, תפקוד מחסום, ותנועתיות

Assay Galvanotaxis לניתוח של קינטיקס נדידת תאים העצביים המבשר בשדה חשמלי נוכחי לשימוש חיצוני ישיר

Mutagenesis וניתוח פונקציונלי של תעלות יונים הביעו Heterologously בתאי יונקים

Transfection אסטרטגיה אופטימיזציה עבור הביטוי הקלטה של ​​אלקטרו Voltage-מגודרת ערוצי רקומביננטי יון ב HEK-293T תאים

Microinjection מתא בודד לניתוח תקשורת נייד

גאפ junctional אינטר תקשורת: ביומרקר פונקציונלית להערכת תופעות לוואי של toxicants ורעלים, ואת היתרונות הבריאותיים של מוצרים טבעיים

Assay תקשורת צומת-המערכת יודיד-צהוב הניאון חלבון-Gap

Transfection אסטרטגיה אופטימיזציה עבור הביטוי הקלטה של אלקטרו Voltage-מגודרת ערוצי רקומביננטי יון ב HEK-293T תאים