Name: identification of homologous recombination events in mouse embryonic stem cells using southern blotting and polymerase chain reaction
Uploaded: 2018-11-20T13:30:00
Description: Watch this Scientific Journal Video about Identification of Homologous Recombination Events in Mouse Embryonic Stem Cells Using Southern Blotting and Polymerase Chain Reaction at JoVE.com

This work received support from the General Program of National Natural Science Foundation of China (Grants No. 31571432), the Human Provincial Natural Science Foundation of China (Grant No. 2015JC3097), and the Research Foundation of Education Bureau of Hunan Province, China (Grant No. 15K054).

1. Design of Targeting Construct(s), Probes for Southern Blot, and Primers for PCR
<ol>
	<li>Select the first coding exon (exon 2) of the Myh9 gene for disruption or insertion in the application of knockout/knock-in reported here.</li>
	<li>Retrieve the 5-kb upstream and 5-kb downstream DNA sequences surrounding the Myh9 exon 2 from the genome.ucsc.edu website.</li>
	<li>Analyze restriction digestion patterns of enzymes (REs) with 1&#8211;2 cuts in this 10-kb region by using pDRAW software to determine...

<ol>
	<li>Gao, G., McMahon, C., Chen, J., Rong, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+powerful+method+combining+homologous+recombination+and+site-specific+recombination+for+targeted+mutagenesis+in+Drosophila.">A powerful method combining homologous recombination and site-specific recombination for targeted mutagenesis in Drosophila.</a> Proceedings of the National Academy of Sciences of the United States of America. 105 (37), 13999-14004 (2008).</li><li>Skarnes, W., 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=A+conditional+knockout+resource+for+the+genome-wide+study+of+mouse+gene+function.">A conditional knockout resource for the genome-wide study of mouse gene function.</a> Nature. 474 (7351), 337-342 (2011).</li><li>Vogel, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nobel+Prizes.+A+knockout+award+in+medicine.">Nobel Prizes. A knockout award in medicine.</a> Science. 318 (5848), 178-179 (2007).</li><li>Salsman, J., Dellaire, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Precision+genome+editing+in+the+CRISPR+era.">Precision genome editing in the CRISPR era.</a> Biochemistry. Cell Biology. 95 (2), 187-201 (2017).</li><li>Capecchi, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gene+targeting+in+mice:+functional+analysis+of+the+mammalian+genome+for+the+twenty-first+century.">Gene targeting in mice: functional analysis of the mammalian genome for the twenty-first century.</a> Nature Reviews Genetics. 6 (6), 507-512 (2005).</li><li>Van, d. W. L., Adams, D. J., Bradley, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tools+for+targeted+manipulation+of+the+mouse+genome.">Tools for targeted manipulation of the mouse genome.</a> Physiological Genomics. 11 (3), 133-164 (2002).</li><li>Glaser, S., Anastassiadis, K., Stewart, A. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Current+issues+in+mouse+genome+engineering.">Current issues in mouse genome engineering.</a> Nature Genetics. 37 (11), 1187 (2005).</li><li>Bradley, A., Evans, M., Kaufman, M. H., Robertson, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Formation+of+germ-line+chimaeras+from+embryo-derived+teratocarcinoma+cell+lines.">Formation of germ-line chimaeras from embryo-derived teratocarcinoma cell lines.</a> Nature. 309 (5965), 255-256 (1984).</li><li>Robertson, E., Bradley, A., Kuehn, M., Evans, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Germ-line+transmission+of+genes+introduced+into+cultured+pluripotential+cells+by+retroviral+vector.">Germ-line transmission of genes introduced into cultured pluripotential cells by retroviral vector.</a> Nature. 323 (6087), 445-448 (1986).</li><li>Thomas, K. R., Capecchi, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Site-directed+mutagenesis+by+gene+targeting+in+mouse+embryo-derived+stem+cells.">Site-directed mutagenesis by gene targeting in mouse embryo-derived stem cells.</a> Cell. 51 (3), 503-512 (1987).</li><li>Skarnes, W. C., 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=A+conditional+knockout+resource+for+the+genome-wide+study+of+mouse+gene+function.">A conditional knockout resource for the genome-wide study of mouse gene function.</a> Nature. 474 (7351), 337 (2011).</li><li>Collins, F. S., Rossant, J., Wurst, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+mouse+for+all+reasons.">A mouse for all reasons.</a> Cell. 128 (1), 9-13 (2007).</li><li>Poueymirou, W. T., 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=F0+generation+mice+fully+derived+from+gene-targeted+embryonic+stem+cells+allowing+immediate+phenotypic+analyses.">F0 generation mice fully derived from gene-targeted embryonic stem cells allowing immediate phenotypic analyses.</a> Nature Biotechnology. 25 (1), 91-99 (2007).</li><li>Pettitt, S. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Agouti+C57BL/6N+embryonic+stem+cells+for+mouse+genetic+resources.">Agouti C57BL/6N embryonic stem cells for mouse genetic resources.</a> Nature Methods. 6 (7), 493-495 (2009).</li><li>Gertsenstein, 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=Efficient+Generation+of+Germ+Line+Transmitting+Chimeras+from+C57BL/6N+ES+Cells+by+Aggregation+with+Outbred+Host+Embryos.">Efficient Generation of Germ Line Transmitting Chimeras from C57BL/6N ES Cells by Aggregation with Outbred Host Embryos.</a> PLoS One. 5 (6), 11260 (2012).</li><li>Smithies, O., Gregg, R. G., Boggs, S. S., Koralewski, M. A., Kucherlapati, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insertion+of+DNA+sequences+into+the+human+chromosomal+|[beta]|-globin+locus+by+homologous+recombination.">Insertion of DNA sequences into the human chromosomal |[beta]|-globin locus by homologous recombination.</a> Nature. 317 (6034), 230-234 (1985).</li><li>Deng, C., Capecchi, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reexamination+of+gene+targeting+frequency+as+a+function+of+the+extent+of+homology+between+the+targeting+vector+and+the+target+locus.">Reexamination of gene targeting frequency as a function of the extent of homology between the targeting vector and the target locus.</a> Molecular &amp; Cellular Biology. 12 (8), 3365 (1992).</li><li>Lay, J. M., Friishansen, L., Gillespie, P. J., Samuelson, L. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+confirmation+of+gene+targeting+in+embryonic+stem+cells+using+two+long-range+PCR+techniques.">Rapid confirmation of gene targeting in embryonic stem cells using two long-range PCR techniques.</a> Transgenic Research. 7 (2), 135-140 (1998).</li><li>Langerak, P., Nygren, A. O. H., Schouten, J. P., Jacobs, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+and+quantitative+detection+of+homologous+and+non-homologous+recombination+events+using+three+oligonucleotide+MLPA.">Rapid and quantitative detection of homologous and non-homologous recombination events using three oligonucleotide MLPA.</a> Nucleic Acids Research. 33 (22), 188 (2005).</li><li>G&#243;mezrodr&#237;guez, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Advantages+of+q-PCR+as+a+method+of+screening+for+gene+targeting+in+mammalian+cells+using+conventional+and+whole+BAC-based+constructs.">Advantages of q-PCR as a method of screening for gene targeting in mammalian cells using conventional and whole BAC-based constructs.</a> Nucleic Acids Research. 36 (18), 117 (2008).</li><li>Kim, H. S., Smithies, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recombinant+fragment+assay+for+gene+targeting+based+on+the+polymerase+chain+reaction.">Recombinant fragment assay for gene targeting based on the polymerase chain reaction.</a> Nucleic Acids Research. 16 (18), 8887-8903 (1988).</li><li>Joyner, A. L., Skarnes, W. C., Rossant, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Production+of+a+mutation+in+mouse+En-2+gene+by+homologous+recombination+in+embryonic+stem+cells.">Production of a mutation in mouse En-2 gene by homologous recombination in embryonic stem cells.</a> Nature. 338 (6211), 153-156 (1989).</li><li>Ma, X., Adelstein, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+vertebrate+nonmuscle+Myosin+II+in+development+and+human+disease.">The role of vertebrate nonmuscle Myosin II in development and human disease.</a> Bioarchitecture. 4 (3), 88-102 (2014).</li><li>Malonek, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Relationships+between+the+dynamics+of+cortical+blood+flow,+oxygenation,+and+volume+changes+following+sensory+stimulation.">Relationships between the dynamics of cortical blood flow, oxygenation, and volume changes following sensory stimulation.</a> Proceedings of the National Academy of Sciences of the United States of America. 94, (1997).</li><li>Takeda, K., Kishi, H., Ma, X., Yu, Z. X., Adelstein, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ablation+and+mutation+of+nonmuscle+myosin+heavy+chain+II-B+results+in+a+defect+in+cardiac+myocyte+cytokinesis.">Ablation and mutation of nonmuscle myosin heavy chain II-B results in a defect in cardiac myocyte cytokinesis.</a> Circulation Research. 93 (4), 330-337 (2003).</li><li>Conti, M. A., Evenram, S., Liu, C., Yamada, K. M., Adelstein, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Defects+in+cell+adhesion+and+the+visceral+endoderm+following+ablation+of+nonmuscle+myosin+heavy+chain+II-A+in+mice.">Defects in cell adhesion and the visceral endoderm following ablation of nonmuscle myosin heavy chain II-A in mice.</a> Journal of Biological Chemistry. 279 (40), 41263-41266 (2004).</li><li>Wang, A., 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=Nonmuscle+myosin+II+isoform+and+domain+specificity+during+early+mouse+development.">Nonmuscle myosin II isoform and domain specificity during early mouse development.</a> Proceedings of the National Academy of Sciences of the United States of America. 107 (33), 14645-14650 (2010).</li><li>Zhang, Y., 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=Mouse+models+of+MYH9-related+disease:+mutations+in+nonmuscle+myosin+II-A.">Mouse models of MYH9-related disease: mutations in nonmuscle myosin II-A.</a> Blood. 119 (1), 238 (2012).</li><li>Liu, T., 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=Identification+and+characterization+of+MYH9+locus+for+high+efficient+gene+knock-in+and+stable+expression+in+mouse+embryonic+stem+cells.">Identification and characterization of MYH9 locus for high efficient gene knock-in and stable expression in mouse embryonic stem cells.</a> PLoS One. 13 (2), 0192641 (2018).</li><li>Saito, S., Adachi, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Advances+in+the+Development+of+Gene-Targeting+Vectors+to+Increase+the+Efficiency+of+Genetic+Modification.">Advances in the Development of Gene-Targeting Vectors to Increase the Efficiency of Genetic Modification.</a> Biological &amp; Pharmaceutical Bulletin. 39 (1), 25-32 (2016).</li><li>Langerak, P., Nygren, A., Schouten, J., Jacobs, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rapid+and+quantitative+detection+of+homologous+and+non-homologous+recombination+events+using+three+oligonucleotide+MLPA.">Rapid and quantitative detection of homologous and non-homologous recombination events using three oligonucleotide MLPA.</a> Nucleic Acids Research. 33 (22), 188 (2005).</li><li>Martin, S. 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=A+single+amino+acid+substitution+in+ORF1+dramatically+decreases+L1+retrotransposition+and+provides+insight+into+nucleic+acid+chaperone+activity.">A single amino acid substitution in ORF1 dramatically decreases L1 retrotransposition and provides insight into nucleic acid chaperone activity.</a> Nucleic Acids Research. 36 (18), 5845-5854 (2008).</li><li>Kamisugi, Y., Cuming, A. C., Cove, 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=Parameters+determining+the+efficiency+of+gene+targeting+in+the+moss+Physcomitrella+patens.">Parameters determining the efficiency of gene targeting in the moss Physcomitrella patens.</a> Nucleic Acids Research. 33 (19), 173 (2005).</li><li>Luo, Y., Bolund, L., S&#248;rensen, C. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pig+gene+knockout+by+rAAV-mediated+homologous+recombination:+comparison+of+BRCA1+gene+knockout+efficiency+in+Yucatan+and+G&#246;ttingen+fibroblasts+with+slightly+different+target+sequences.">Pig gene knockout by rAAV-mediated homologous recombination: comparison of BRCA1 gene knockout efficiency in Yucatan and G&#246;ttingen fibroblasts with slightly different target sequences.</a> Transgenic Research. 21 (3), 671-676 (2012).</li><li>Croning, M. D., Fricker, D. G., Komiyama, N. H., Grant, S. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Automated+design+of+genomic+Southern+blot+probes.">Automated design of genomic Southern blot probes.</a> BMC Genomics. 11 (1), 74 (2010).</li><li>Zimmer, A., Gruss, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Production+of+chimaeric+mice+containing+embryonic+stem+(ES)+cells+carrying+a+homoeobox+Hox+1.1+allele+mutated+by+homologous+recombination.">Production of chimaeric mice containing embryonic stem (ES) cells carrying a homoeobox Hox 1.1 allele mutated by homologous recombination.</a> Nature. 338 (6211), 150-153 (1989).</li></ol>

Currently, designer nucleases for genome editing still cannot replace ES cell-based gene-targeting technology due to its issues of off-target effects, and difficulty in inserting a long DNA fragment30,31. As the golden methods for identifying HR events that occurred in mouse ES cells, this report provides a detailed protocol of Southern blotting and PCR for the field. We validated the reliability of these methods by analyzing individual clones from mouse ES cells...

The technology of gene targeting by HR in murine ES cells provides a powerful tool for dissecting the cellular consequences of specific genetic mutations1,2. The importance and significance of this technology are reflected in its recognition by the 2007 Nobel Prize in Physiology or Medicine3,4; meanwhile, it represents the advent of the modern era of gene engineering5. Gene targeting through HR can be utilized to engineer virtually any alteration ranging from point mutations to large chromosomal rearrangements in the genome of mouse ES cells6,7. It is well known that, before the emergence of so-called genome editing tools, the generation of a gene knockout mouse required the application of gene-targeting technology in ES cells8,9,10. During the past two decades, more than 5,000 gene-targeted mice were produced by this approach for modeling human diseases or studying gene functions11. A genome-wide knockout effort has been established for distributing gene-targeting vectors, targeted ES cell clones, and live mice to the scientific community2,12,13,14,15. Undoubtedly, ES cell-based HR-mediated gene-targeting technology has greatly advanced our understanding of the functions of genes played in physiological or pathological context.
Because HR is a relatively infrequent event in mammalian cells16,17, the important and next step following gene targeting in murine ES cells is to analyze numerous ES colonies for identifying a few clones with mutations resulting from HR with the targeting vector18. The gold methods for identifying HR events include Southern blotting and PCR19,20. The advantages of the approaches include that Southern blotting can identify correctly targeted ES clones and allows researchers to analyze the structure of the gene-targeted event, such as a verification of a single copy insertion of the construct, while a PCR-based strategy permits more rapid screening for HR events21,22. Though these methods have drawbacks, such as that they are time-consuming and can have false positives, the combinational usage of them is widely accepted and applied by most labs in identifying HR events, particular in ES cells, for generating genetically modified animals.
Three isoforms of nonmuscle myosin II (NM II) in mammals, each consisting of two identical NMHC IIs which are encoded by three different genes (named Myh9, Myh10, and Myh14) and two pairs of light chains, are referred to as NM II-A, II-B, and II-C23. Previous studies have indicated that at least the isoforms of NM II-A and II-B are essential for mouse development because the in vivo ablation of these isoforms results in embryonic lethality24,25,26. To circumvent this problem and obtain novel insights into the isoform-specific functions of NM II-A and II-B in the later stages of mouse development, a genetic replacement strategy using ES cell-based HR-mediated gene-targeting technology was adopted to generate a series of mouse models27. In the course of identifying the desired ES clones, both Southern blotting and PCR methods were utilized, and these proved to be efficient and reliable27,28.
This paper intends to provide a detailed description of Southern blotting and PCR, including the design of targeting vector(s), probe(s), and primers, and the execution of experiments, as well as the analysis of results exemplified by identifying HR event occurrence in ES cells for creating genetic replacement NM II mouse models and representative data. The protocols of these two methods presented here can also be adopted for identifying the genotypes of genetically modified cells or animals.

<table border="0" cellpadding="0" cellspacing="0" style="width:903px;" width="903">
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		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:391px;">BAC CLONE</td>
			<td style="width:232px;">BACPAC Resources Center (BPRC)</td>
			<td style="width:113px;">bMQ-330E21</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">QIAGEN Large-Construct Kit</td>
			<td style="width:232px;">QIAGEN</td>
			<td align="right">12462</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">QIAquick Gel Extraction Kit</td>
			<td style="width:232px;">QIAGEN</td>
			<td align="right" style="width:113px;">28704</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">QIAquick PCR Purification Kit</td>
			<td style="width:232px;">QIAGEN</td>
			<td align="right" style="width:113px;">28104</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">QIAprep Spin Miniprep Kit</td>
			<td style="width:232px;">QIAGEN</td>
			<td align="right" style="width:113px;">27104</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">QIAGEN Plasmid Plus Maxi Kit</td>
			<td style="width:232px;">QIAGEN</td>
			<td align="right" style="width:113px;">12963</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">PfuUltra High-Fidelity DNA Polymerase</td>
			<td style="width:232px;">Agilent</td>
			<td align="right" style="width:113px;">600382</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:391px;">T-easy vector</td>
			<td style="width:232px;">Promega</td>
			<td style="width:113px;">A1360</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:391px;">Nuclei Lysis Solution</td>
			<td style="width:232px;">Promega</td>
			<td style="width:113px;">A7941</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Protein Precipitation Solution</td>
			<td style="width:232px;">Promega</td>
			<td>A7951</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">DNA Denaturing Solution</td>
			<td style="width:232px;">VWR</td>
			<td>351-013-131</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">DNA Neutralizing Solution</td>
			<td style="width:232px;">VWR</td>
			<td>351-014-131</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ready-To-Go DNA Labeling Beads (-dCTP)</td>
			<td style="width:232px;">VWR</td>
			<td>27-9240-01</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">UltraPure SSC, 20X</td>
			<td style="width:232px;">Thermo Fisher</td>
			<td align="right">15557036</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">UltraPur Phenol:Chloroform:Isoamyl Alcohol (25:24:1, v/v)</td>
			<td style="width:232px;">Thermo Fisher</td>
			<td align="right">15593031</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">G418</td>
			<td style="width:232px;">Thermo Fisher</td>
			<td align="right">10131035</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Salmon Sperm DNA Solution</td>
			<td style="width:232px;">Thermo Fisher</td>
			<td align="right">15632011</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Platinu Taq DNA Polymerase High Fidelity</td>
			<td style="width:232px;">Thermo Fisher</td>
			<td align="right">11304029</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:391px;">Not I</td>
			<td>Thermo Scientific</td>
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identification of homologous recombination events in mouse embryonic stem cells using southern blotting and polymerase chain reaction

Relative to the issues of off-target effects and the difficulty of inserting a long DNA fragment in the application of designer nucleases for genome editing, embryonic stem (ES) cell-based gene-targeting technology does not have these shortcomings and is widely used to modify animal/mouse genome ranging from large deletions/insertions to single nucleotide substitutions. Notably, identifying the relatively few homologous recombination (HR) events necessary to obtain desired ES clones is a key step, which demands accurate and reliable methods. Southern blotting and/or conventional PCR are often utilized for this purpose. Here, we describe the detailed procedures of using those two methods to identify HR events that occurred in mouse ES cells in which the endogenous Myh9 gene is intended to be disrupted and replaced by cDNAs encoding other nonmuscle myosin heavy chain IIs (NMHC IIs). The whole procedure of Southern blotting includes the construction of targeting vector(s), electroporation, drug selection, the expansion and storage of ES cells/clones, the preparation, digestion, and blotting of genomic DNA (gDNA), the hybridization and washing of probe(s), and a final step of autoradiography on the X-ray films. PCR can be performed directly with prepared and diluted gDNA. To obtain ideal results, the probes and restriction enzyme (RE) cutting sites for Southern blotting and the primers for PCR should be carefully planned. Though the execution of Southern blotting is time-consuming and labor-intensive and PCR results have false positives, the correct identification by Southern blotting and the rapid screening by PCR allow the sole or combined application of these methods described in this paper to be widely used and consulted by most labs in the identification of genotypes of ES cells and genetically modified animals.

In this paper, a detailed protocol of Southern blotting and PCR is described, which is utilized to identify HR events that occurred in mouse ES cells for the generation of NM II genetic replacement mouse models, using ES cells-based HR-mediated targeting technology. Though Southern blotting and PCR, as well as traditional gene-targeting technology, have been widely used for several decades, the successful application of them needs to be planned carefully. At least these aspects are requir...

Watch this Scientific Journal Video about Identification of Homologous Recombination Events in Mouse Embryonic Stem Cells Using Southern Blotting and Polymerase Chain Reaction at JoVE.com

Identification of Homologous Recombination Events in Mouse Embryonic Stem Cells Using Southern Blotting and Polymerase Chain Reaction (Video) | JoVE

Here, we present a detailed protocol for identifying homologous recombination events that occurred in mouse embryonic stem cells using Southern blotting and/or PCR. This method is exemplified by the generation of nonmuscle myosin II genetic replacement mouse models using traditional embryonic stem cell-based homologous recombination-mediated targeting technology.

Identification of Homologous Recombination Events in Mouse Embryonic Stem Cells Using Southern Blotting and Polymerase Chain Reaction

Relative to the issues of off-target effects and the difficulty of inserting a long DNA fragment in the application of designer nucleases for genome ...

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Improved Polymerase Chain Reaction-restriction Fragment Length Polymorphism Genotyping of Toxic Pufferfish by Liquid Chromatography/Mass Spectrometry

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Semi-quantitative Detection of RNA-dependent RNA Polymerase Activity of Human Telomerase Reverse Transcriptase Protein

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CRISPR-Mediated Reorganization of Chromatin Loop Structure

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Endogenous Protein Tagging in Human Induced Pluripotent Stem Cells Using CRISPR/Cas9

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Evaluation of a Universal Nested Reverse Transcription Polymerase Chain Reaction for the Detection of Lyssaviruses

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To detect rabies virus and other member species of the genus Lyssavirus within the family Rhabdoviridae, the pan-lyssavirus nested reverse transcription ...

Artificial RNA Polymerase II Elongation Complexes for Dissecting Co-transcriptional RNA Processing Events

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A Robust Polymerase Chain Reaction-based Assay for Quantifying Cytosine-guanine-guanine Trinucleotide Repeats in Fragile X Mental Retardation-1 Gene

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