This project was funded by the European Social Funds in Baden-Wuerttemberg, Germany.

1. Augmentation of Plasmids Containing Required Coding DNA Sequences (CDS)
<ol>
	<li>Pre-warm SOC medium, which is included in the transformation kit, to room temperature and the LB agar plates containing 100 &#181;g/ml ampicillin to 37 &#176;C. Equilibrate the water bath to 42 &#176;C.</li>
	<li>Thaw one vial of chemically component E. coli on ice.</li>
	<li>Add 1-5 &#181;l of the plasmid (10 pg to 100 ng) containing the CDS into the vial of chemically component E. coli and mix gently. Do not mix the cells by pipetting. After adding plasmids, mix by tapping the tube gently.</li>
	<li>Incubate the mixture on ice for 30 min.</li>
	<li>Heat-shock the E. coli for 30 sec at 42 &#176;C in a water bath without shaking.</li>
	<li>Place the vial on ice for 2 min.</li>
	<li>Add 250 &#181;l of pre-warmed SOC medium to the E. coli and shake the bacteria horizontally at 300 rpm for 1 hr at 37 &#176;C in a bacterial incubator.</li>
	<li>Spread 100 &#181;l and 150 &#181;l from transformation mix on pre-warmed LB agar plates, invert the plates and incubate overnight at 37 &#176;C.</li>
	<li>After colonies become visible, inoculate a single colony from each plate into a 15 ml culture tube containing 5 ml LB medium with 100 &#181;g/ml ampicillin. Incubate them overnight at 37 &#176;C with shaking at 300 rpm until culture is in late log or stationary phase.</li>
	<li>For long-term storage of transformed E. coli, pipet 75 &#181;l of 100% glycerol into the cryovial. Add 225 &#181;l of the bacterial culture (frozen stock will contain 25% glycerol), mix well and store the cryovial at -80 &#176;C.</li>
	<li>Isolate the plasmids containing the required CDS using a plasmid purification kit according to manufacturer&#39;s instructions.</li>
	<li>Determine the plasmid concentration using a spectrophotometer.</li>
	<li>Prepare aliquots of 20 &#181;l and store them at -20 &#176;C for prolonged time.</li>
</ol>
2. Amplification of Plasmid Inserts and Adding of Poly T-tail by Polymerase Chain Reaction (PCR)
<ol>
	<li>NOTE: To obtain the DNA template for the in vitro transcription (IVT), the CDS of interest, here eGFP, is amplified using PCR. Simultaneously, a poly T-tail of 120 thymidines (T) is added to the insert by using a reverse primer with a T120 extension. Thereby, the generated mRNAs obtain a poly A-tail with a defined length after the IVT.</li>
	<li>Prepare PCR mixture as detailed in Table 1.</li>
	<li>Mix the reaction mix thoroughly. NOTE: PCR product can be used in 4-5 IVT reactions. To increase the DNA template amount for IVT, total volume of the PCR mixture can be increased. Several PCR tubes each containing 100 &#181;l PCR mixture can be used to obtain a sufficient yield of PCR product.</li>
	<li>Place the PCR tubes in a thermocycler and run the PCR using the PCR cycling protocol (Table 2).</li>
	<li>Clean up the PCR reaction using a PCR purification kit according to manufacturer&#39;s instructions and elute the DNA using 20 &#181;l nuclease-free water.</li>
	<li>Measure the concentration of the DNA using a spectrophotometer. NOTE: The detected DNA concentration is approximately 300 &#181;g/ml. Thus, the expected total amount should be ~6 &#181;g. The amount of DNA for other proteins can differ depending on the length of CDS, amount of plasmid used for PCR, annealing temperature of primers, and cycle number.</li>
	<li>Freeze the DNA at -20 &#176;C for a long time or use it directly for IVT.</li>
</ol>
3. Control Step: Quality of PCR Product
<ol>
	<li>Check the quality of the PCR product by DNA gel electrophoresis.</li>
	<li>Mix the desired amount of agarose with 1x TBE in a flask. For a 1% agarose gel, add 0.5 g of agarose to 50 ml of 1x TBE.</li>
	<li>Microwave until the agarose is dissolved. Do not let it boil. Ensure that the agarose is completely in solution.</li>
	<li>Add 5 &#181;l nucleic acid gel stain to 50 ml agarose gel.</li>
	<li>Pour the gel into an agarose gel box, set the comb, and wait approximately 1 hr until the gel solidified.</li>
	<li>Remove the comb and place the gel box in a gel tray.</li>
	<li>Mix 2 &#181;l (200 ng) of 80-10,000 bp DNA-Ladder and 200 ng of PCR product each with 2 &#181;l 6x loading buffer in a total volume of 12 &#181;l.</li>
	<li>Carefully load DNA samples into the wells of the agarose gel.</li>
	<li>Using 1x TBE as running buffer, run the agarose gel at 100 V for 1 hr.</li>
	<li>Visualize the DNA bands on an imaging system (Figure 2).</li>
</ol>
4. In Vitro Transcription (IVT)
<ol>
	<li>NOTE: After PCR, the plasmid inserts are amplified and a poly T-tail is added. During the IVT, genetic information is transcribed from DNA to RNA. The generated mRNA transcript is used to produce proteins in cells.</li>
	<li>Clean the working area and pipettes with an RNase decontamination solution. Use PCR clean and sterile dual-filter pipette tips and frequently change gloves to minimize contamination of reaction mixes with RNases.</li>
	<li>Prepare the NTP/cap analog mixture as described in Table 3.</li>
	<li>Mix the NTP/cap analog mixture thoroughly by vortexing and spin down briefly.</li>
	<li>Assemble the IVT reaction mixture as described in Table 4.</li>
	<li>Mix the IVT reaction mixture thoroughly by gently pipetting up and down. Then centrifuge the PCR tube briefly to collect the mixture at the bottom of the tube.</li>
	<li>Incubate at 37 &#176;C for 3 hr in a thermomixer. 
	NOTE: The optimum incubation time depends on the length of the inserts and transcriptional efficiency of given template. For short inserts (&#60;500 nt), a longer incubation time may be advantageous. A time-course experiment can be done to determine the optimum incubation time for maximum yield. Therefore, set up IVT reactions, for example, for 1, 2, 3, 4, 6 hr, and overnight incubation and determine the mRNA amount. The kinetics of the in vitro transcription for generation of eGFP mRNA is shown in Figure 3.</li>
	<li>To remove the template DNA, add 1 &#181;l of DNase (2 U/&#181;l) to the IVT reaction mixture, mix well and incubate 15 min at 37 &#176;C.</li>
	<li>Purify the reaction mixture using a RNA purification kit according to manufacturer&#180;s instructions. Elute the modified mRNA from the spin column membrane twice with 40 &#181;l nuclease-free water. NOTE: The detected RNA concentration is approximately 1,500 &#181;g/ml. Thus, the expected total amount should be ~120 &#181;g. The amount of synthesized mRNA for other proteins can differ depending on the length of CDS and the amount of PCR product used for IVT.</li>
</ol>
5. Treatment of Purified mRNA with Antarctic Phosphatase
<ol>
	<li>NOTE: The generated mRNA is treated with phosphatase to remove 5&#39; triphosphates, which can be recognized by RIG-I and lead to immune activation. Furthermore, the phosphatase treatment prevents re-circularization in a self-ligation reaction.</li>
	<li>Add 9 &#181;l of 10x Antarctic phosphatase reaction buffer to 79 &#181;l of purified mRNA solution. Subsequently, add 2 &#181;l of Antarctic phosphatase (5 U/&#181;l) and gently mix the sample. Incubate the reaction mixture at 37 &#176;C for 30 min.</li>
	<li>Purify the reaction mixture using a RNA purification kit according to manufacturer&#180;s instructions. Elute the modified mRNA from the spin column membrane twice with 50 &#181;l nuclease-free water.</li>
	<li>Measure the concentration of the modified mRNA using a spectrophotometer. Check that the ratio of absorbance at 260 nm/280 nm (A260/A280) is &#8805; 1.8 and the ratio of A260/A230 is 2.0, which indicates purity. 
	NOTE: The expected total yield should be approximately 90 &#181;g, which is sufficient for approximately 36 mRNA transfections.</li>
	<li>Adjust the concentration of mRNA to 100 ng/&#181;l by adding nuclease-free water.</li>
	<li>Aliquot the modified mRNA into single-use aliquots required for transfections and store at -80 &#176;C. Avoid multiple freeze and thaw cycles. Properly prepared and stored mRNA is stable for many years. During working, always keep the modified mRNA on ice.</li>
</ol>
6. Control Step: Quality of Synthesized Modified mRNA
<ol>
	<li>Check the quality of modified mRNA by RNA gel electrophoresis.</li>
	<li>Mix the desired amount of agarose with 1x TBE in a flask. For a 1% agarose gel, add 0.5 g of agarose to 50 ml of 1x TBE.</li>
	<li>Microwave until the agarose is dissolved. Do not let it boil. Ensure that the agarose is completely in solution.</li>
	<li>Add 5 &#181;l nucleic acid gel stain to 50 ml agarose gel.</li>
	<li>Pour the gel into a agarose gel box, set the comb, and wait approximately 1 hr until the gel is solidified.</li>
	<li>Remove the comb and place the gel box in a gel tray.</li>
	<li>Mix 3 &#181;l (3 &#181;g) of 0.5-10 kb RNA Ladder and 200 ng of synthesized modified mRNA each with 7 &#181;l loading buffer in a total volume of 10 &#181;l. The composition of the loading buffer is described in Table 5.</li>
	<li>Denature the ladder and the mRNA samples at 70 &#176;C for 10 min.</li>
	<li>Carefully load the ladder and the mRNA samples on the 1% agarose gel.</li>
	<li>Perform electrophoresis at 100 V for 1 hr using 1x TBE as running buffer.</li>
	<li>Visualize the ladder and mRNA bands on a UV transilluminator and photograph using a gel documentation system (Figure 4).</li>
</ol>
7. Preparing of Cells for Transfection
<ol>
	<li>Plate 2 x105 cells (HEK293 cells) per well of 12-well plate.</li>
	<li>Incubate the cells overnight at 37 &#176;C in a cell incubator. NOTE: At the day of transfection, the cells should have reached 80-90% confluence.</li>
</ol>
8. Performing mRNA Transfection of Cells
<ol>
	<li>Thaw the modified mRNA.</li>
	<li>Generate the lipoplexes for transfection.</li>
	<li>Add 25 &#181;l (2.5 &#181;g) of modified mRNA and 2 &#181;l of cationic lipid transfection reagent to 473 &#181;l Opti-MEM (Minimal Essential Medium) I reduced serum medium to generate the transfection mixture for transfection of one well of a 12-well plate. Scale up the volumes according to the number of wells to be transfected. As negative control, prepare a transfection mixture without mRNA.</li>
	<li>Mix the components gently by pipetting. Incubate the transfection mixture at room temperature for 20 min to generate lipoplexes for transfection. 
	NOTE: The transfection mixture contains no antibiotics. Thus, take care to ensure the sterility while handling cells.</li>
	<li>Wash cells with 500 &#181;l DPBS/well.</li>
	<li>Add 500 &#181;l transfection mixture to one well of a 12-well plate.</li>
	<li>Incubate the cells for 4 hr at 37 &#176;C and 5% CO2.</li>
	<li>Aspirate the transfection mixture and add 1 ml complete cell culture medium to the cells.</li>
	<li>Incubate the cells for 24 hr in the cell incubator.</li>
	<li>Perform fluorescence microscopic analyses using a fluorescence microscope (Figure 5). NOTE: To examine the expression of other proteins in cells, which are produced by transfection with other mRNA than eGFP coding mRNA, the cells can be cultivated on coverslips. Then the transfection can be performed and the cells can be stained with appropriate antibodies and analyzed by fluorescence microscopy.</li>
</ol>
9. Flow Cytometric Analyses of eGFP Expression in Cells
<ol>
	<li>Remove cell culture medium from the wells and wash each well with 1 ml DPBS (without calcium and magnesium). Add 500 &#181;l trypsin/EDTA per well to detach the cells from the surface of cell culture plates. Subsequently, add 500 &#181;l TNS per well to inactivate trypsin.</li>
	<li>Centrifuge the detached cells for 5 min at 300 x g at room temperature. Remove the supernatant leaving only the pellet. Resuspend the cell pellet in 150 &#181;l cell fixation solution and transfer the cell suspension into a flow cytometry tube.</li>
	<li>Analyze the percentage of eGFP expressing cells and the fluorescence intensity using Geo Mean (geometric mean of fluorescence intensity) (Figure 6).</li>
</ol>
10. Measurement of Protein Expression Over Time
<ol>
	<li>Perform mRNA transfection of cells in 3 wells of a 12-well plate as described in step 8. Additionally, incubate 3 wells of HEK293 cells with the transfection mixture without the addition of mRNA.</li>
	<li>Measure the expression of eGFP 1, 2, and 3 days after transfection to evaluate the duration of protein expression (Figure 7).</li>
</ol>

<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. 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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. 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The authors declare that they have no competing financial interests.

The mRNA therapy has tremendous potential in the field of regenerative medicine, treatment of diseases and vaccination. In this video, we demonstrate the production of a stabilized, modified mRNA for induction of protein expression in cells. Using this protocol, other desired mRNA can be generated. The in vitro synthesis of modified mRNA allows the transfection of cells with desired mRNAs to induce expression of target proteins. Thereby, the desired protein is expressed transiently under physiological conditions...

In cells, the transcription of messenger RNA (mRNA) and the following translation of mRNA into desired proteins ensure the proper functioning of cells. Hereditary or acquired genetic disorders can lead to insufficient and dysfunctional synthesis of proteins and cause severe diseases. Thus, a new therapeutic approach to induce the production of missing or defective proteins is the exogenous delivery of synthetic modified mRNA into cells, which codes for the desired protein. Thereby, cells are triggered to synthesize functional proteins, which they normally cannot produce or would naturally not need. Using this approach, genetic disorders can be corrected by introduction of mRNA that codes for the defective or missing protein 1. The mRNA therapy can also be used for vaccination to synthetize protein antigens, which are expressed by tumor cells or pathogens. Thereby, host immune system can be activated to effectively eliminate tumor cells or prevent infections 2,3. Furthermore, in recent years, mRNA was successfully used to generate induced pluripotent stem cells (iPSCs). For this purpose, fibroblasts were transfected with mRNAs to induce the expression of reprogramming factors 4-6 and to convert them in iPSCs with an enormous potential in regenerative medicine.
Previously, the use of conventional mRNA was associated with low stability and strong immunogenicity. Thus, clinical applications of conventional mRNAs were limited. However, the replacement of cytidine and uridine by 5-methylcytidine and pseudouridine within the mRNA molecule by Kariko and colleagues rendered mRNA molecules stable in biological fluids and dramatically reduced immune activation 7-10, which now allows the clinical applicability of modified mRNAs.
Using synthetically produced modified mRNAs, desired gene transcripts can be temporarily delivered in vivo 11 or in vitro to induce protein expression. The introduced mRNA is translated under physiological conditions by the cellular translation machinery. Due to lack of integration into the host cell genome compared to viral gene therapy vectors, the risk of oncogenesis is prevented 12,13. Thus, therapy using modified synthetic mRNA will get better clinical acceptance in the future.
Here, we describe a detailed protocol for production of modified mRNA (Figure 1), transfection of cells with mRNA and the evaluation of protein expression in transfected cells.

<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

The exogenous delivery of coding synthetic messenger RNA (mRNA) for induction of protein synthesis in desired cells has enormous potential in the fields of regenerative medicine, basic cell biology, treatment of diseases, and reprogramming of cells. Here, we describe a step by step protocol for generation of modified mRNA with reduced immune activation potential and increased stability, quality control of produced mRNA, transfection of cells with mRNA and verification of the induced protein expression by flow cytometry. Up to 3 days after a single transfection with eGFP mRNA, the transfected HEK293 cells produce eGFP. In this video article, the synthesis of eGFP mRNA is described as an example. However, the procedure can be applied for production of other desired mRNA. Using the synthetic modified mRNA, cells can be induced to transiently express the desired proteins, which they normally would not express.

Using a pcDNA 3.3 plasmid containing the CDS of eGFP, the synthesis of modified eGFP mRNA was established (Figure 1). After insert amplification by PCR and poly T-tailing, a clear band with a length of approximately 1,100 bp is detected (Figure 2). Increasing the IVT time augmented the yield of mRNA (Figure 3). After the IVT, a clear mRNA band with a length of approximately 1,100 bp was detected, which corresponds to the length of eGFP mRNA to be produced (Figure...

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

In this video article, we describe the in vitro synthesis of modified mRNA for induction of protein expression in cells.

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

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

in-vitro-synthesis-modified-mrna-for-induction-protein-expression

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JoVE Journal

Biology

24.8K Views.  University Hospital Tuebingen. In this video article, we describe the in vitro synthesis of modified mRNA for induction of protein expression in cells.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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