פרויקט זה מומן על ידי קרנות החברתיות האירופיות באדן-וירטמברג, גרמניה.

<ol>
	<li>Bangel-Ruland, 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=CFTR-mRNA+delivery:+a+novel+alternative+for+cystic+fibrosis+&amp;#34;gene+therapy&amp;#34;.">CFTR-mRNA delivery: a novel alternative for cystic fibrosis &amp;#34;gene therapy&amp;#34;.</a> The journal of gene medicine. , (2013).</li><li>Benteyn, D., 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=Design+of+an+Optimized+Wilms&amp;#34;+Tumor+1+(WT1)+mRNA+Construct+for+Enhanced+WT1+Expression+and+Improved+Immunogenicity+In+Vitro+and+In+Vivo.">Design of an Optimized Wilms&amp;#34; Tumor 1 (WT1) mRNA Construct for Enhanced WT1 Expression and Improved Immunogenicity In Vitro and In Vivo.</a> Molecular therapy Nucleic acids. 2, 134 (2013).</li><li>Petsch, 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=Protective+efficacy+of+in+vitro+synthesized,+specific+mRNA+vaccines+against+influenza+A+virus+infection.">Protective efficacy of in vitro synthesized, specific mRNA vaccines against influenza A virus infection.</a> Nature. 30, 1210-1216 (2012).</li><li>Mandal, P. K., Rossi, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reprogramming+human+fibroblasts+to+pluripotency+using+modified+mRNA.">Reprogramming human fibroblasts to pluripotency using modified mRNA.</a> Nature protocols. 8, 568-582 (2013).</li><li>Warren, 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=Highly+efficient+reprogramming+to+pluripotency+and+directed+differentiation+of+human+cells+with+synthetic+modified+mRNA.">Highly efficient reprogramming to pluripotency and directed differentiation of human cells with synthetic modified mRNA.</a> Cell stem cell. 7, 618-630 (2010).</li><li>Yakubov, E., Rechavi, G., Rozenblatt, S., Givol, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reprogramming+of+human+fibroblasts+to+pluripotent+stem+cells+using+mRNA+of+four+transcription+factors.">Reprogramming of human fibroblasts to pluripotent stem cells using mRNA of four transcription factors.</a> Biochemical and biophysical research communications. 394, 189-193 (2010).</li><li>Anderson, B. R., 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=Incorporation+of+pseudouridine+into+mRNA+enhances+translation+by+diminishing+PKR+activation.">Incorporation of pseudouridine into mRNA enhances translation by diminishing PKR activation.</a> Nucleic acids research. 38, 5884-5892 (2010).</li><li>Kariko, K., Buckstein, M., Ni, H., Weissman, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Suppression+of+RNA+recognition+by+Toll-like+receptors:+the+impact+of+nucleoside+modification+and+the+evolutionary+origin+of+RNA.">Suppression of RNA recognition by Toll-like receptors: the impact of nucleoside modification and the evolutionary origin of RNA.</a> Immunity. 23, 165-175 (2005).</li><li>Kariko, K., 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=Incorporation+of+pseudouridine+into+mRNA+yields+superior+nonimmunogenic+vector+with+increased+translational+capacity+and+biological+stability.">Incorporation of pseudouridine into mRNA yields superior nonimmunogenic vector with increased translational capacity and biological stability.</a> Molecular therapy : the journal of the American Society of Gene Therapy. 16, 1833-1840 (2008).</li><li>Kariko, K., Weissman, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Naturally+occurring+nucleoside+modifications+suppress+the+immunostimulatory+activity+of+RNA:+implication+for+therapeutic+RNA+development.">Naturally occurring nucleoside modifications suppress the immunostimulatory activity of RNA: implication for therapeutic RNA development.</a> Current opinion in drug discovery &amp; development. 10, 523-532 (2007).</li><li>Kormann, M. S., 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=Expression+of+therapeutic+proteins+after+delivery+of+chemically+modified+mRNA+in+mice.">Expression of therapeutic proteins after delivery of chemically modified mRNA in mice.</a> Nature biotechnology. 29, 154-157 (2011).</li><li>Hacein-Bey-Abina, S., 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=Insertional+oncogenesis+in+4+patients+after+retrovirus-mediated+gene+therapy+of+SCID-X1.">Insertional oncogenesis in 4 patients after retrovirus-mediated gene therapy of SCID-X1.</a> The Journal of clinical investigation. 118, 3132-3142 (2008).</li><li>Hacein-Bey-Abina, S., 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=Efficacy+of+gene+therapy+for+X-linked+severe+combined+immunodeficiency.">Efficacy of gene therapy for X-linked severe combined immunodeficiency.</a> The New England journal of medicine. 363, 355-364 (2010).</li><li>Avci-Adali, M., 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=Optimized+conditions+for+successful+transfection+of+human+endothelial+cells+with+in+vitro+synthesized+and+modified+mRNA+for+induction+of+protein+expression.">Optimized conditions for successful transfection of human endothelial cells with in vitro synthesized and modified mRNA for induction of protein expression.</a> Journal of biological engineering. 8, 8 (2014).</li></ol>

החוקרים מצהירים כי אין להם אינטרסים כלכליים מתחרים.

יש טיפול mRNA פוטנציאל עצום בתחום של רפואת רגנרטיבית, טיפול במחלות וחיסונים. בסרטון הזה, אנחנו מדגימים את הייצור של ה- mRNA התייצב, שונה לזירוז של ביטוי חלבון בתאים. שימוש בפרוטוקול זה, יכול להיות שנוצר mRNA הרצוי אחר. הסינתזה במבחנה של mRNA שונה מאפשרת transfection של תאים עם mRN...

בתאים, השעתוק של RNA שליח (mRNA) והתרגום הבא של ה- mRNA לחלבונים רצויים להבטיח את התפקוד התקין של תאים. הפרעות גנטיות תורשתיות או נרכשות יכולות להוביל לסינתזה מספיקה ולא מתפקדת של חלבונים וגורמות למחלות קשות. כך, גישה טיפולית חדשה ללעורר את הייצור של חלבונים חסרים או פגומים הוא המשלוח אקסוגני של סינטטי שונה mRNA לתאים, שקודים לחלבון הרצוי. וכך, תאים מופעלים לסנתז חלבונים פונקציונליים, שבו הם בדרך כלל לא יכולים לייצר או באופן טבעי לא צריכים. שימוש בגישה זו, ניתן לתקן הפרעות גנטיות על ידי הקדמה של mRNA שמקודד לחלבון הפגום או חסר 1. גם טיפול mRNA יכול לשמש לחיסון לאנטיגנים synthetize חלבון, אשר באים לידי ביטוי על ידי תאי גידול או פתוגנים. ובכך, מערכת חיסונית מארח יכולה להיות מופעלת כדי לחסל ביעילות תאים סרטניים או למנוע infections 2,3. יתר על כן, בשנים האחרונות, mRNA היה בהצלחה המשמש לייצור תאים מושרה pluripotent גזע (iPSCs). לצורך כך, fibroblasts היה transfected עם mRNAs לגרום הביטוי של תכנות מחדש גורמי 4-6 ולהמיר אותם בiPSCs עם פוטנציאל עצום ברפואת רגנרטיבית. בעבר, השימוש בmRNA הקונבנציונלי היה קשור ביציבות נמוכה וחיסוני חזקים. כך, יישומים קליניים של mRNAs הקונבנציונלי היו מוגבלים. עם זאת, החלפת cytidine וuridine על ידי 5-methylcytidine וpseudouridine בתוך מולקולת mRNA על ידי Kariko ועמיתים שניתנו מולקולות mRNA יציבים בנוזלים ביולוגיים והפחתה דרמטית בהפעלת מערכת חיסונית 7-10, אשר כעת מאפשרת יישום הקליני של mRNAs שונה. באמצעות מיוצר באופן סינטטי mRNAs שונה, תמלילי גן רצויים יכולים להיות מועברים באופן זמני בvivo 11או במבחנה כדי לגרום לביטוי חלבון. MRNA הציג מתורגם בתנאים פיסיולוגיים על ידי מכונות תרגום הסלולריות. בשל חוסר האינטגרציה לתוך הגנום של התא הפונדקאי לעומת וקטורי ריפוי גנטי נגיפיים, הסיכון של oncogenesis נמנע 12,13. כך, טיפול באמצעות mRNA הסינתטי שונה יקבל קבלה קלינית טובה יותר בעתיד. כאן אנו מתארים פרוטוקול מפורט לייצור של ה- mRNA שונה, transfection של תאים עם mRNA וההערכה של ביטוי חלבון בתאי transfected (איור 1).

<table border="0" cellpadding="0" cellspacing="0" width="1058">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:295px;">Name of Material/ Equipment</td>
			<td style="width:157px;">Company</td>
			<td style="width:172px;">Catalog Number</td>
			<td style="width:435px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:295px;">Cell culture</td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">DMEM, high glucose</td>
			<td>PAA</td>
			<td>E15-009</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">FBS</td>
			<td>Life Technologies</td>
			<td>10500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Penicillin/Streptomycin&#160;</td>
			<td style="width:157px;">PAA</td>
			<td>P11-010</td>
			<td>100x</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">L-glutamine&#160;</td>
			<td>PAA</td>
			<td>M11-004</td>
			<td>200 mM</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">DPBS without calcium and magnesium&#160;</td>
			<td>PAA</td>
			<td>E15-002</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">0.04% Trypsin / 0.03% EDTA&#160;</td>
			<td>Promocell</td>
			<td>C-41020</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">TNS</td>
			<td>Promocell</td>
			<td>C-41120</td>
			<td style="width:435px;">Trypsin Neutralizing Solution, 0.05% trypsin inhibitor in 0.1% BSA</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">HEK-293 cells</td>
			<td style="width:157px;">ATCC</td>
			<td>CRL-1573</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:295px;"></td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Consumables</td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Tissue culture plates, 12-well&#160;</td>
			<td>Corning</td>
			<td>3512</td>
			<td></td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">Cell culture flask (75 cm2)&#160;</td>
			<td>Corning</td>
			<td>430641</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:295px;">DNase-and RNase-free 1.5 ml sterile microcentrifuge tubes&#160;</td>
			<td>Eppendorf</td>
			<td>0030 121.589</td>
			<td>Safe-Lock, Biopur</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">15 ml conical tubes&#160;</td>
			<td>greiner bio-one</td>
			<td>188271</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:295px;">PCR clean and sterile epT.I.P.S. dualfilter pipette tips&#160;</td>
			<td>Eppendorf</td>
			<td style="width:172px;">10 &#181;l: 022491202,&#160;&#160;&#160; 100 &#181;l: 022491237, 1000 &#181;l: 022491253</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cryovial</td>
			<td>greiner bio-one</td>
			<td>122279-128</td>
			<td>Cryo.s&#160;</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:295px;">14 ml polypropylene round bottom tube for bacterial culture&#160;</td>
			<td>BD Falcon</td>
			<td>352059</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:295px;"></td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Plasmid amplification and purification</td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">pcDNA 3.3_eGFP Plasmid&#160;</td>
			<td style="width:157px;">Addgene</td>
			<td>26822</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:295px;">One Shot Top10 chemically component Escherichia coli&#160;</td>
			<td>Invitrogen</td>
			<td>C4040-10</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:295px;">Sterile water (Ampuwa)</td>
			<td>Fresenius Kabi</td>
			<td>1636071</td>
			<td></td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">LB medium (Luria/Miller)&#160;</td>
			<td>Carl Roth</td>
			<td>X968.1</td>
			<td>Dissolve 25 g l-1 in sterile water.</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">LB agar (Luria/Miller)&#160;</td>
			<td>Carl Roth</td>
			<td>X969.1</td>
			<td>Dissolve 40 g l-1 in sterile water.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ampicillin Ready Made Solution</td>
			<td>Sigma Aldrich</td>
			<td>A5354</td>
			<td>100 mg/ml&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Glycerol</td>
			<td>Sigma Aldrich</td>
			<td>G2025</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">QIAprep Spin Miniprep Kit&#160;</td>
			<td>Qiagen</td>
			<td>27104</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:295px;"></td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">mRNA production</td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">HotStar HiFidelity Polymerase Kit&#160;</td>
			<td>Qiagen</td>
			<td>202602</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">QIAquick PCR Purification Kit&#160;</td>
			<td>Qiagen</td>
			<td>28106</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">MEGAscript T7 Kit&#160;</td>
			<td>Life Technologies</td>
			<td>AM1334</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">5-Methylcytidine-5&#180;-triphosphate&#160;</td>
			<td>Trilink</td>
			<td>N1014</td>
			<td>5-Methyl-CTP</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Pseudouridine-5&#180;-triphosphate&#160;</td>
			<td>Trilink</td>
			<td>N1019</td>
			<td>Pseudo-UTP</td>
		</tr>
		<tr height="45">
			<td height="45" style="height:45px;width:295px;">3&#180;-O-Me-m7G(5&#180;)ppp(5`)G RNA cap structure analog&#160;</td>
			<td>New England Biolabs</td>
			<td>S1411L</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">RiboLock RNase Inhibitor</td>
			<td>Thermo Scientific</td>
			<td>EO0381</td>
			<td>40 U/&#181;l&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">TURBO DNase</td>
			<td>Life Technologies</td>
			<td>AM1334</td>
			<td>2 U/&#181;l (from MEGAscript T7 Kit)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Antarctic phosphatase&#160;</td>
			<td>New England Biolabs</td>
			<td>MO289S</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">RNeasy mini kit&#160;</td>
			<td>Qiagen</td>
			<td>74104</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">RNaseZap solution&#160;</td>
			<td>Life Technologies</td>
			<td>AM9780</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:295px;"></td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Transfection</td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Lipofectamine 2000 Transfection Reagent&#160;</td>
			<td>Invitrogen</td>
			<td>11668-019</td>
			<td>Cationic lipid transfection reagent</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Opti-MEM I Reduced Serum Media&#160;</td>
			<td>Invitrogen</td>
			<td>11058-021</td>
			<td style="width:435px;">Improved Minimal Essential Medium (MEM) with&#160; reduced Fetal Bovine Serum (FBS) supplementation&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:295px;"></td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Gel electrophoresis</td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Agarose</td>
			<td>Sigma-Aldrich</td>
			<td>A9539</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Gelred Nucleic Acid Gel Stain</td>
			<td>Biotium</td>
			<td>41003</td>
			<td>10,000x in water&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">peqGOLD Range Mix DNA-Ladder&#160;</td>
			<td>Peqlab</td>
			<td>25-2210</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">0.5-10 kb RNA Ladder&#160;</td>
			<td>Invitrogen</td>
			<td>15623-200</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">1x TBE buffer</td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:295px;"></td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Flow cytometry analyses</td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">CellFIX (1x)</td>
			<td>BD Biosciences</td>
			<td>340181</td>
			<td>10x concentrate&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:295px;"></td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:295px;">Primer for insert amplification and&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; poly (T) tail PCR</td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Forward Primer (HPLC-grade) 10 &#181;M</td>
			<td style="width:157px;">Ella Biotech</td>
			<td style="width:172px;"></td>
			<td>5&#180;-TTGGACCCTCGTACAGAAGCTAATACG-3&#180;</td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">Reverse Primer (HPLC-grade) 10 &#181;M</td>
			<td style="width:157px;">Ella Biotech</td>
			<td style="width:172px;"></td>
			<td>5&#180;- T120-CTTCCTACTCAGGCTTTATTCAAAGACCA-3&#180;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:295px;"></td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Equipment</td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">Cell incubator</td>
			<td>Binder</td>
			<td style="width:172px;"></td>
			<td>CO2 (5%) and O2 (20%)&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">CASY cell counter&#160;</td>
			<td>Sch&#228;rfe System</td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="44">
			<td height="44" style="height:44px;">Sterile workbench&#160;</td>
			<td style="width:157px;">BDK Luft-und Reinraumtecknik GmbH</td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Bacterial incubator&#160;</td>
			<td>Incutec</td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Water bath</td>
			<td style="width:157px;"></td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">ScanDrop spectrophotometer&#160;</td>
			<td>Analytic Jena</td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">PCR thermocycler&#160;</td>
			<td>Eppendorf</td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Microcentrifuge</td>
			<td>Eppendorf</td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Vortex</td>
			<td>peqlab</td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Thermomixer</td>
			<td>Eppendorf</td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Gel apparatus for electrophoresis&#160;</td>
			<td>Bio-Rad</td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Gel documentation system&#160;</td>
			<td>Bio-Rad</td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">FACScan System&#160;</td>
			<td>BD Biosciences</td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Fluorescence microscope&#160;</td>
			<td>Nikon</td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Phase-contrast microscope&#160;</td>
			<td>Zeiss</td>
			<td style="width:172px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

in vitro synthesis of modified mrna for induction of protein expression in human cells

המשלוח אקסוגני של קידוד RNA שליח סינטטי (mRNA) לזירוז סינתזה של חלבונים בתאים רצויים יש פוטנציאל עצום בתחומים של רפואת רגנרטיבית, ביולוגיה של תא בסיסי, טיפול במחלות, ותכנות מחדש של תאים. כאן, אנו מתארים צעד אחר צעד פרוטוקול לדור של mRNA שונה עם פוטנציאל מופחת חיסוני הפעלה ויציבות מוגברת, בקרת איכות של ה- mRNA מיוצר, transfection של תאים עם mRNA ואימות של ביטוי חלבון הנגרם על ידי זרימת cytometry. עד 3 ימים לאחר transfection יחיד עם eGFP mRNA, HEK293 תאי transfected לייצר eGFP. במאמר זה וידאו, הסינתזה של eGFP mRNA מתוארת כדוגמא. עם זאת, ההליך יכול להיות מיושם לייצור של ה- mRNA הרצוי האחר. שימוש בסינטטי שונה mRNA, יכולים להיגרם תאים לבטא את החלבונים הרצויים, שבו הם בדרך כלל לא מביעים זמניים.

באמצעות פלסמיד pcDNA 3.3 המכיל את ה- CDS של eGFP, הסינתזה של eGFP mRNA שונה הוקמה (איור 1). לאחר הגברה להוסיף על ידי PCR ופולי T-עוקב, להקה ברורה באורך של כ -1,100 נ&quot;ב הוא זוהה (איור 2). הגדלת זמן IVT Augmented התשואה של mRNA (איור 3). לאחר IVT, להקת mRNA ברורה באורך של כ -1,100 נ&q...

Watch this Scientific Journal Video about In Vitro Synthesis of Modified mRNA for Induction of Protein Expression in Human Cells at JoVE.com

In Vitro Synthesis of Modified mRNA for Induction of Protein Expression in Human Cells

במאמר זה וידאו, אנו מתארים את הסינתזה במבחנה של mRNA שונה לזירוז של ביטוי חלבון בתאים.

במבחנת הסינתזה של mRNA השתנה לאינדוקציה של ביטוי חלבון בתאים אנושיים

The exogenous delivery of coding synthetic messenger RNA (mRNA) for induction of protein synthesis in desired cells has enormous potential in the fields ...

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JoVE Journal

Biology

In Vitro Synthesis of Modified mRNA for Induction of Protein Expression in Human Cells

24.8K Views.  University Hospital Tuebingen.  במאמר זה וידאו, אנו מתארים את הסינתזה במבחנה של mRNA שונה לזירוז של ביטוי חלבון בתאים. 

Video: In Vitro Synthesis of Modified mRNA for Induction of Protein Expression in Human Cells

In vitro Labeling of Human Embryonic Stem Cells for Magnetic Resonance Imaging

Human embryonic stem cells (hESC) have demonstrated the ability to restore the injured myocardium. Magnetic resonance imaging (MRI) has emerged as one of the predominant imaging modalities to assess the restoration of the injured myocardium. Furthermore, ex-vivo labeling agents, such as iron-oxide nanoparticles, have been employed to track and localize the transplanted stem cells. However, this method does not monitor a fundamental cellular biology property regarding the viability of transplanted cells. It has been known that manganese chloride (MnCl2) enters the cells via voltage-gated calcium (Ca2+) channels when the cells are biologically active, and accumulates intracellularly to generate T1 shortening effect. Therefore, we suggest that manganese-guided MRI can be useful to monitor cell viability after the transplantation of hESC into the myocardium.
In this video, we will show how to label hESC with MnCl2 and how those cells can be clearly seen by using MRI in vitro. At the same time, biological activity of Ca2+-channels will be modulated utilizing both Ca2+-channel agonist and antagonist to evaluate concomitant signal changes.

In this video, we are showing how to label human embryonic stem cells (hESC) with manganese chloride (MnCl2) which can enter cells via voltage-gated calcium channels when the cells are biologically active. Additionally, we show the use of MnCl2 as cellular MRI contrast agent to determine the in vitro viability of hESC.

ב סימון במבחנה של בתאי גזע עובריים אנושיים עבור דימות תהודה מגנטית

Human embryonic stem cells (hESC) have demonstrated the ability to restore the injured myocardium. Magnetic resonance imaging (MRI) has emerged as one of ...

Staining of Proteins in Gels with Coomassie G-250 without Organic Solvent and Acetic Acid

In classical protein staining protocols using Coomassie Brilliant Blue (CBB), solutions with high contents of toxic and flammable organic solvents (Methanol, Ethanol or 2-Propanol) and acetic acid are used for fixation, staining and destaining of proteins in a gel after SDS-PAGE. To speed up the procedure, heating the staining solution in the microwave oven for a short time is frequently used. This usually results in evaporation of toxic or hazardous Methanol, Ethanol or 2-Propanol and a strong smell of acetic acid in the lab which should be avoided due to safety considerations. In a protocol originally published in two patent applications by E.M. Wondrak (US2001046709 (A1), US6319720 (B1)), an alternative composition of the staining solution is described in which no organic solvent or acid is used. The CBB is dissolved in bidistilled water (60-80mg of CBB G-250 per liter) and 35 mM HCl is added as the only other compound in the staining solution. The CBB staning of the gel is done after SDS-PAGE and thorough washing of the gel in bidistilled water. By heating the gel during the washing and staining steps, the process can be finished faster and no toxic or hazardous compunds are evaporating. The staining of proteins occurs already within 1 minute after heating the gel in staining solution and is fully developed after 15-30 min with a slightly blue background that is destained completely by prolonged washing of the stained gel in bidistilled water, without affecting the stained protein bands.

A short protocol for protein staining with Coomassie Brilliant Blue (CBB) G-250 in polyacrylamide gels is described without using organic solvents or acetic acid as in the classical staining procedures with CBB.

הכתמה של חלבונים עם ג&#39;ל Coomassie G-250 ללא חומצה אצטית ממס אורגני

In classical protein staining protocols using Coomassie Brilliant Blue (CBB), solutions with high contents of toxic and flammable organic solvents ...

Purification of the M. magneticum Strain AMB-1 Magnetosome Associated Protein MamA&Delta;41

Magnetotactic bacteria comprise a diverse group of aquatic microorganisms that are able to orientate themselves along geomagnetic fields. This behavior is believed to aid their search for suitable environments (1). This capability is conferred by the magnetosome, a subcellular organelle that consists of a linear-chain assembly of lipid vesicles each able to biomineralize and enclose a ~50-nm crystal of magnetite or greigite. A principle component of the magnetosome that was shown to be required for the formation of functional vesicles is MamA. MamA is a highly abundant magnetosome-associated protein which is one of the most characterized magnetosome-associated proteins in vivo (2-6). This article focuses on the purification of MamA, which despite being studied in vivo, no clear functional or structural details have been identified for it. Bioinformatics analysis suggested that MamA is a tetra-tricopeptide repeat (TPR) containing protein. TPR is a structural motif found as such or forming part of a bigger fold in a wide range of proteins, it serves as a template for protein-protein interactions and mediates multi-protein complexes (7). TPRs are involved in many crucial tasks in eukaryotic cell organelle processes and many bacterial pathways (8-14). In order to understand MamA, a unique TPR containing protein, highly purified protein is required as a first step. In this article, we present the purification protocol for a stable MamA deletion mutant (MamA&Delta;41) from M. magneticum AMB-1.

Purification of the &lt;em&gt;M. magneticum&lt;/em&gt; Strain AMB-1 Magnetosome Associated Protein MamA&amp;Delta;41

MamA is a unique Magnetosome associated protein which was shown to be involved in magnetosome activation. Here we present the purification protocol of MamA deletion mutant (MamA&Delta;41) from M. magneticum AMB-1.

טיהור של מ magneticum מסננים השגריר-1 Magnetosome חלבון Associated MamAΔ41

Magnetotactic bacteria comprise a diverse group of aquatic microorganisms that are able to orientate themselves along geomagnetic fields. This behavior is ...

In vitro Reconstitution of the Active T. castaneum Telomerase

Efforts to isolate the catalytic subunit of telomerase, TERT, in sufficient quantities for structural studies, have been met with limited success for more than a decade. Here, we present methods for the isolation of the recombinant Tribolium castaneum TERT (TcTERT) and the reconstitution of the active T. castaneum telomerase ribonucleoprotein (RNP) complex in vitro.
Telomerase is a specialized reverse transcriptase1 that adds short DNA repeats, called telomeres, to the 3' end of linear chromosomes2 that serve to protect them from end-to-end fusion and degradation. Following DNA replication, a short segment is lost at the end of the chromosome3 and without telomerase, cells continue dividing until eventually reaching their Hayflick Limit4. Additionally, telomerase is dormant in most somatic cells5 in adults, but is active in cancer cells6 where it promotes cell immortality7.
The minimal telomerase enzyme consists of two core components: the protein subunit (TERT), which comprises the catalytic subunit of the enzyme and an integral RNA component (TER), which contains the template TERT uses to synthesize telomeres8,9. Prior to 2008, only structures for individual telomerase domains had been solved10,11. A major breakthrough in this field came from the determination of the crystal structure of the active12, catalytic subunit of T. castaneum telomerase, TcTERT1.
Here, we present methods for producing large quantities of the active, soluble TcTERT for structural and biochemical studies, and the reconstitution of the telomerase RNP complex in vitro for telomerase activity assays. An overview of the experimental methods used is shown in Figure 1.

In vitro Reconstitution of the Active T. castaneum Telomerase

Efforts to isolate the catalytic subunit of telomerase, TERT, in sufficient quantities for structural studies, have been met with limited success for more than a decade. Here, we present methods for the isolation of the recombinant Tribolium castaneum TERT (TcTERT) and the reconstitution of the active T. castaneum telomerase ribonucleoprotein (RNP) complex in vitro.

ב הכינון במבחנה של ט פעילים castaneum שהטלומרז

Efforts to isolate the catalytic subunit of telomerase, TERT, in sufficient quantities for structural studies, have been met with limited success for more ...

Efficient Derivation of Human Cardiac Precursors and Cardiomyocytes from Pluripotent Human Embryonic Stem Cells with Small Molecule Induction

To date, the lack of a suitable human cardiac cell source has been the major setback in regenerating the human myocardium, either by cell-based transplantation or by cardiac tissue engineering1-3. Cardiomyocytes become terminally-differentiated soon after birth and lose their ability to proliferate. There is no evidence that stem/progenitor cells derived from other sources, such as the bone marrow or the cord blood, are able to give rise to the contractile heart muscle cells following transplantation into the heart1-3. The need to regenerate or repair the damaged heart muscle has not been met by adult stem cell therapy, either endogenous or via cell delivery1-3. The genetically stable human embryonic stem cells (hESCs) have unlimited expansion ability and unrestricted plasticity, proffering a pluripotent reservoir for in vitro derivation of large supplies of human somatic cells that are restricted to the lineage in need of repair and regeneration4,5. Due to the prevalence of cardiovascular disease worldwide and acute shortage of donor organs, there is intense interest in developing hESC-based therapies as an alternative approach. However, how to channel the wide differentiation potential of pluripotent hESCs efficiently and predictably to a desired phenotype has been a major challenge for both developmental study and clinical translation. Conventional approaches rely on multi-lineage inclination of pluripotent cells through spontaneous germ layer differentiation, resulting in inefficient and uncontrollable lineage-commitment that is often followed by phenotypic heterogeneity and instability, hence, a high risk of tumorigenicity6-8 (see a schematic in Fig. 1A). In addition, undefined foreign/animal biological supplements and/or feeders that have typically been used for the isolation, expansion, and differentiation of hESCs may make direct use of such cell-specialized grafts in patients problematic9-11. To overcome these obstacles, we have resolved the elements of a defined culture system necessary and sufficient for sustaining the epiblast pluripotence of hESCs, serving as a platform for de novo derivation of clinically-suitable hESCs and effectively directing such hESCs uniformly towards clinically-relevant lineages by small molecules12 (see a schematic in Fig. 1B). After screening a variety of small molecules and growth factors, we found that such defined conditions rendered nicotinamide (NAM) sufficient to induce the specification of cardiomesoderm direct from pluripotent hESCs that further progressed to cardioblasts that generated human beating cardiomyocytes with high efficiency (Fig. 2). We defined conditions for induction of cardioblasts direct from pluripotent hESCs without an intervening multi-lineage embryoid body stage, enabling well-controlled efficient derivation of a large supply of human cardiac cells across the spectrum of developmental stages for cell-based therapeutics.

We have established a protocol for induction of cardioblasts direct from pluripotent human embryonic stem cells maintained under defined conditions with small molecules, which enables derivation of a large supply of human cardiac progenitors and functional cardiomyocytes for cardiovascular repair.

גזירת יעיל של מבשרי לב cardiomyocytes האדם מן האדם תאים pluripotent גזע עובריים עם אינדוקציה מולקולה קטנה

To date, the lack of a suitable human cardiac cell source has been the major setback in regenerating the human myocardium, either by cell-based ...

Isolation of Ribosome Bound Nascent Polypeptides in vitro to Identify Translational Pause Sites Along mRNA

The rate of translational elongation is non-uniform. mRNA secondary structure, codon usage and mRNA associated proteins may alter ribosome movement on the messagefor review see 1. However, it's now widely accepted that synonymous codon usage is the primary cause of non-uniform translational elongation rates1. Synonymous codons are not used with identical frequency. A bias exists in the use of synonymous codons with some codons used more frequently than others2. Codon bias is organism as well as tissue specific2,3. Moreover, frequency of codon usage is directly proportional to the concentrations of cognate tRNAs4. Thus, a frequently used codon will have higher multitude of corresponding tRNAs, which further implies that a frequent codon will be translated faster than an infrequent one. Thus, regions on mRNA enriched in rare codons (potential pause sites) will as a rule slow down ribosome movement on the message and cause accumulation of nascent peptides of the respective sizes5-8. These pause sites can have functional impact on the protein expression, mRNA stability and protein foldingfor review see 9. Indeed, it was shown that alleviation of such pause sites can alter ribosome movement on mRNA and subsequently may affect the efficiency of co-translational (in vivo) protein folding1,7,10,11. To understand the process of protein folding in vivo, in the cell, that is ultimately coupled to the process of protein synthesis it is essential to gain comprehensive insights into the impact of codon usage/tRNA content on the movement of ribosomes along mRNA during translational elongation.
Here we describe a simple technique that can be used to locate major translation pause sites for a given mRNA translated in various cell-free systems6-8. This procedure is based on isolation of nascent polypeptides accumulating on ribosomes during in vitro translation of a target mRNA. The rationale is that at low-frequency codons, the increase in the residence time of the ribosomes results in increased amounts of nascent peptides of the corresponding sizes. In vitro transcribed mRNA is used for in vitro translational reactions in the presence of radioactively labeled amino acids to allow the detection of the nascent chains. In order to isolate ribosome bound nascent polypeptide complexes the translation reaction is layered on top of 30% glycerol solution followed by centrifugation. Nascent polypeptides in polysomal pellet are further treated with ribonuclease A and resolved by SDS PAGE. This technique can be potentially used for any protein and allows analysis of ribosome movement along mRNA and the detection of the major pause sites. Additionally, this protocol can be adapted to study factors and conditions that can alter ribosome movement and thus potentially can also alter the function/conformation of the protein.

Isolation of Ribosome Bound Nascent Polypeptides in vitro to Identify Translational Pause Sites Along mRNA

A technique to identify translational pause sites on mRNA is described. This procedure is based on isolation of nascent polypeptides accumulating on ribosomes during in vitro translation of a target mRNA, followed by the size analysis of the nascent chains using a denaturing gel electrophoresis.

הבידוד של הריבוזום פוליפפטידים המתהווה כרוכים<em&gt; במבחנה</em&gt; כדי לזהות אתרים השהה של תרגום לאורך ה-mRNA

The rate of translational elongation is non-uniform. mRNA secondary structure, codon usage and mRNA associated proteins may alter ribosome movement on the ...

Efficient Generation Human Induced Pluripotent Stem Cells from Human Somatic Cells with Sendai-virus

A few years ago, the establishment of human induced pluripotent stem cells (iPSCs) ushered in a new era in biomedicine. Potential uses of human iPSCs include modeling pathogenesis of human genetic diseases, autologous cell therapy after gene correction, and personalized drug screening by providing a source of patient-specific and symptom relevant cells. However, there are several hurdles to overcome, such as eliminating the remaining reprogramming factor transgene expression after human iPSCs production. More importantly, residual transgene expression in undifferentiated human iPSCs could hamper proper differentiations and misguide the interpretation of disease-relevant in vitro phenotypes. With this reason, integration-free and/or transgene-free human iPSCs have been developed using several methods, such as adenovirus, the piggyBac system, minicircle vector, episomal vectors, direct protein delivery and synthesized mRNA. However, efficiency of reprogramming using integration-free methods is quite low in most cases.
Here, we present a method to isolate human iPSCs by using Sendai-virus (RNA virus) based reprogramming system. This reprogramming method shows consistent results and high efficiency in cost-effective manner.

Here, we present our established method to reprogram human somatic cells into transgene-free human iPSCs with Sendai virus, which shows consistent outcome and enhanced efficiency.

תאי גזע יעיל דור מושרה אדם פלוריפוטנטיים מתאים הסומטיים של אדם עם סנדאי וירוס

A few years ago, the establishment of human induced pluripotent stem cells (iPSCs) ushered in a new era in biomedicine. Potential uses of human iPSCs ...

Profiling Individual Human Embryonic Stem Cells by Quantitative RT-PCR

Heterogeneity of stem cell population hampers detailed understanding of stem cell biology, such as their differentiation propensity toward different lineages. A single cell transcriptome assay can be a new approach for dissecting individual variation. We have developed the single cell qRT-PCR method, and confirmed that this method works well in several gene expression profiles. In single cell level, each human embryonic stem cell, sorted by OCT4::EGFP positive cells, has high expression in OCT4, but a different level of NANOG expression. Our single cell gene expression assay should be useful to interrogate population heterogeneities.

Single cell gene expression assay is needed for understanding stem cell heterogeneities.

אפיון תאי גזע עוברי האנושי על ידי הפרט כמותי RT-PCR

Heterogeneity of stem cell population hampers detailed understanding of stem cell biology, such as their differentiation propensity toward different ...

Analysis of Global RNA Synthesis at the Single Cell Level following Hypoxia

Hypoxia or lowering of the oxygen availability is involved in many physiological and pathological processes. At the molecular level, cells initiate a particular transcriptional program in order to mount an appropriate and coordinated cellular response. The cell possesses several oxygen sensor enzymes that require molecular oxygen as cofactor for their activity. These range from prolyl-hydroxylases to histone demethylases. The majority of studies analyzing cellular responses to hypoxia are based on cellular populations and average studies, and as such single cell analysis of hypoxic cells are seldom performed. Here we describe a method of analysis of global RNA synthesis at the single cell level in hypoxia by using Click-iT RNA imaging kits in an oxygen controlled workstation, followed by microscopy analysis and quantification.&nbsp; Using cancer cells exposed to hypoxia for different lengths of time, RNA is labeled and measured in each cell. This analysis allows the visualization of temporal and cell-to-cell changes in global RNA synthesis following hypoxic stress.

We describe a technique for analysis of global RNA synthesis in hypoxia using imaging. Click-chemistry labeling of RNA has not previously been performed under hypoxia and allows visualization of global RNA changes at the single cell level. This approach complements the existing averaged RNA techniques, allowing direct visualization of cell-to-cell changes in global RNA synthesis.

ניתוח של גלובל RNA סינתזה ברמת התא בודד הבאות היפוקסיה

Hypoxia or lowering of the oxygen availability is involved in many physiological and pathological processes. At the molecular level, cells initiate a ...

siRNA Screening to Identify Ubiquitin and Ubiquitin-like System Regulators of Biological Pathways in Cultured Mammalian Cells

Post-translational modification of proteins with ubiquitin and ubiquitin-like molecules (UBLs) is emerging as a dynamic cellular signaling network that regulates diverse biological pathways including the hypoxia response, proteostasis, the DNA damage response and transcription.&#160; To better understand how UBLs regulate pathways relevant to human disease, we have compiled a human siRNA &#8220;ubiquitome&#8221; library consisting of 1,186 siRNA duplex pools targeting all known and predicted components of UBL system pathways. This library can be screened against a range of cell lines expressing reporters of diverse biological pathways to determine which UBL components act as positive or negative regulators of the pathway in question.&#160; Here, we describe a protocol utilizing this library to identify ubiquitome-regulators of the HIF1A-mediated cellular response to hypoxia using a transcription-based luciferase reporter.&#160; An initial assay development stage is performed to establish suitable screening parameters of the cell line before performing the screen in three stages: primary, secondary and tertiary/deconvolution screening. &#160;The use of targeted over whole genome siRNA libraries is becoming increasingly popular as it offers the advantage of reporting only on members of the pathway with which the investigators are most interested.&#160; Despite inherent limitations of siRNA screening, in particular false-positives caused by siRNA off-target effects, the identification of genuine novel regulators of the pathways in question outweigh these shortcomings, which can be overcome by performing a series of carefully undertaken control experiments.

Here, we describe a methodology to perform a targeted siRNA &#8220;ubiquitome&#8221; screen to identify novel ubiquitin and ubiquitin-like regulators of the HIF1A-mediated cellular response to hypoxia.&#160; This can be adapted to any biological pathway where a robust read out of reporter activity is available.

הקרנת siRNA לזיהוי יוביקוויטין ורגולטורים מערכת דמויות יוביקוויטין של מסלולים ביולוגיים בתאי יונקים בתרבית

Post-translational modification of proteins with ubiquitin and ubiquitin-like molecules (UBLs) is emerging as a dynamic cellular signaling network that ...