We narrowed to 587 results for: cel.2;
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TypeBlog Post... systems to engineer better and faster ABEs (Fig. 2). These systems allow for rapid continuous protein...and less stringent phage selection. Figure 2: Phage-assisted evolution of base-editing activity...gives a talk at the Cell Symposia: Gene- and Cell-based Therapies: CRISPR, Stem Cells, and Beyond meeting...III product is produced and can infect bacterial cells. If a phage does not deliver an active variant, ...passage from the infected to a fresh uninfected host cell culture). This dilution step represents the major...but gets manually passaged from an infected host-cell culture to an uninfected culture which results in...
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Treating Muscular Dystrophy with CRISPR Gene Editing
TypeBlog Post...high percentage of muscle cells throughout the body, especially stem cells 2. Remove any immunogenicity...nonsense-mediated decay. Although Nelson et al. observed only 2% genome editing in one experiment, they found the ...Science. 2015 Dec 31. doi:10.1126/science.aae0169 2. Long C, Amoasii L, Mireault AA, McAnally JR, Li H...persist over time, stem cell editing would be highly desirable. Should stem cell editing occur, the CRISPR...patient myoblasts; when injected into DMD mice, these cells expressed functional dystrophin. Editing genes in...in vivo is of course much more difficult than in cell culture, but Ran et al. have shown that CRISPR and...be delivered to both cardiac and skeletal muscle cells, where precision editing of the dystrophin gene ... -
CRISPR 101: Epigenetics and Editing the Epigenome
TypeBlog Post...targeted DNA demethylation. Cell Discovery 2: . https://doi.org/10.1038/celldisc.2016.9 Find plasmids from...form or as ready-to-use lentivirus. Figure 2: dCas9-Tet1 demethylates cytosines at promoters and...pX330a dCas9-LSD1 for targeted removal of H3K4me1/2 and H3K9me2 histone modifications. Like the TALE-LSD1...mammalian cells. Co-expression markers EGFP and PuroR enable sorting and selection of transduced cells. Grant...in the Mammalian Genome. Cell 167:233–247.e17 . https://doi.org/10.1016/j.cell.2016.08.056 Find plasmids...the epigenome may make certain processes, like cellular reprogramming of iPSCs, more efficient. In general...for targeted cytosine demethylation in mammalian cells. This plasmid is used with pcDNA3.1-MS2-Tet1-CD ... -
Recombinase-based State Machines Enable Order-dependent Logic in vivo
TypeBlog Post... machines in living cells. Science. 353, aad8559 (2016). PubMed PMID: 27463678. 2. Green, Alexander A....certain states of interest. For example, in Figure 2 below we present a two-input, five-state GRSM register...linking RSM inputs to endogenous gene expression (2). Our paper (1) explains how to arrange attB-attP... require minimal cellular perturbation. Also, this method requires live, intact cells; the sequencing ...Synthetic recombinase-based state machines in living cells” (1), into a more straight-forward, concise explanation...mutations, and environmental conditions drive certain cellular behaviors, but little is known about the order... may be used to better understand and engineer cellular processes that are influenced by temporally ordered... -
Antibodies 101: Polyclonal Antibodies
TypeBlog Post...animal is given additional booster immunizations every 2-3 weeks to increase the antibody titer. The titer ...level of antibodies is reached - typically within 2-4 months. After the animal has the desired level of...system, antibodies are produced by B cells. Each individual B cell produces antibodies that all recognize...also all the same isotype. But together, all the B cell clones in the immune system make different isotypes...antibodies starts with selecting just one of these B cell clones for further antibody production, polyclonal... blood from the immunized animal. The red blood cells and the serum are separated, and the serum - which... -
Plasmids 101: Repressible Promoters
TypeBlog Post...immediate early gene expression. Genes Dev. 1988 Jun;2(6):718-29. doi: 10.1101/gad.2.6.718. PMID: 2843425...Targeted Gene Expression in Drosophila.” Genetics 186(2) (2010): 735-55. PubMed PMID: 20697123. PubMed Central... in Saccharomyces cerevisiae.” FEMS Yeast Res. 12(2) (2012): 197-214. PubMed PMID: 22129153. Additional... by ~3,300-fold in Drosophila cells and ~24,000-fold in human HeLa cells as compared to basal expression...origins, Tet systems function well in mammalian cells, and TRE-containing promoters can be used in the...cumate switch system functions well in mammalian cells, and can be used in the repressible manner described...While originally developed for use in mammalian cells, this system has also been implemented in a variety... -
Summer SciComm: Preprints
TypeBlog Post... to share information about the emerging SARS-CoV-2 virus quickly and openly. By sharing results faster...Open Scientific Communication Ecosystem Fig. 2: The scientific ecosystem, enriched by open access...from peer-reviewed publishing in a journal. Accelerating Scientific Communication Preprints have been...Fig. 1: Stand aside, CERN - it's a new age of accelerating science! Photo courtesy of under a CC license...Lacy was also employed by the American Society for Cell Biology in a position working with preprints in ... -
Teaching an Old DOG New Tricks: Controlling Protein Activity with GFP
TypeBlog Post...from this publication at Addgene. 2. Tang, Jonathan C.Y., et al. “Cell type-specific manipulation with ...successfully regulated expression of channelrhodopsin-2, commonly used in optogenetics, opening up the possibility...lines expressing GFP in specific cell types to do more than just label cells. If GFP could be co-opted to ...reporter output was observed in their 293 cell culture system. In cells cotransfected with GFP and the GBPs,...expression was induced in ~76% of GFP+ cells, and 100% of DsRed+ cells also expressed GFP. Using AAV constructs...fluorescent proteins as scaffolds for cell-specific gene manipulation.” Cell 154(4) (2013): 928-939. PubMed ...wanted to express a variety of proteins in single cell types in the mouse, but knew it would take years... -
CRISPR Methods for Bacteria: Genome Engineering, CRISPRa, CRISPRi, Base Editing, and More
TypeBlog Post... pCRISPomyces-2 contains Cas9 and a gRNA cassette. The simpler system of pCRISPomyces-2 displays a higher...and a subsequent curing protocol that requires only 2-3 hours incubation. E. coli and T. citrea scarless...four major components including (1) a CRISPR RNA, (2) four proteins forming the QCascade DNA-targeting ...Control of Gene Expression. Cell 152:1173–1183 . https://doi.org/10.1016/j.cell.2013.02.022 Ronda C, Pedersen... is primarily a means of selection that targets cells in which homologous recombination has not occurred...ensures high editing efficiency; the only non-edited cells to survive have inactivating mutations in the Cas9...one or more genes in E. coli. and in a mammalian cell line (Qi et al., 2013). Two important features of... -
BeHeard Award 2018: Diseases of Glycosylation, Arginine Mutagenesis, & Neural Development
TypeBlog Post...studies have shown that the conditions Sotos-type 2 and Marshall Smith Syndrome are due to mutations in...accurate diagnosis of NFIX-related syndromes (Sotos-type 2 and Marshall-Smith) and could be expanded to NFIA-...are being awarded free plasmids form Addgene to accelerate their research. Read on to learn how these researchers...the physiological and pathological roles of human cell glycans. Accordingly, she joined efforts with the...aspect of immunology, participating in events such as cell development, recognition and migration, the immune... is not surprising. However, the molecular and cellular mechanisms behind the immune defects in CDG patients...plasmids to immortalize CDG patient-derived immune cell lines and use these lines to study how immune processes... -
Choosing the B(right)est Fluorescent Protein: Photostability
TypeBlog Post...linear fashion. This implies that reducing the power 2-fold does not reduce photobleaching by half. How exactly...prolonged time). Other illumination strategies, such as 2-photon-excitation, selective plane illumination, TIRF...intensity evolves over time in living cells at a power used for live-cell imaging. To conclude, the most photostable...molecule will photobleach at some point. For live-cell imaging, it is desirable to have fluorescent proteins...experiment. The best fluorescent proteins for live cell imaging can be excited many times, thereby producing...these factors, environmental conditions such as cellular redox state and oxygen concentration may affect...protein is a key requirement for quantitative live-cell imaging, it is important to be able to quantify ... -
GPCRs: How Do They Work and How Do We Study Them?
TypeBlog Post...plasmid kit consists of 20 plasmids encoding 14 alpha, 2 beta, and 4 gamma subunits of the heterotrimeric G...activation via bioluminescence resonance energy transfer 2 (BRET2). Check out our blog post on GPCR signaling...with heterotrimeric G proteins on the intracellular side of the cell membrane. Heterotrimeric G proteins...induce or inhibit intracellular signaling cascades as a response to the extracellular stimuli. Ligand dissociation...Peroxidase-Catalyzed Proximity Labeling. Cell 169:338-349.e11 . https://doi.org/10.1016/j.cell.2017.03.028 Roth BL (2016...to the seven alpha helices that transverse the cellular membrane. The receptor recognizes the appropriate...signaling is initiated when a ligand binds to the extracellular surface of the GPCR. This results in a conformational... -
Uncertainty about Labor Law Brings More Uncertainty to Postdoc Wages
TypeBlog Post...increase have had that increase cancelled. Rounding out the remainder, 2% of postdocs who weren’t going...continuing with their plans, and 17 have cancelled their plans. 2 of those raising - the University of Illinois...level, in the case of some public institutions) to cancel plans to raise salaries. What are institutions ...Illinois and the University of Michigan - initially cancelled their plans, but have since reversed their position...announced that they were reversing their plans to cancel raises). A further 9 institutions, whose plans ... In addition, PIs at some of the institutions cancelling plans are going ahead with raises anyway, including...injunction, as we started to hear of institutions cancelling plans to raise salaries, the only postdocs we... -
CRISPR 101: Cas9 vs. The Other Cas(s)
TypeBlog Post...endonuclease of a class 2 CRISPR-Cas system. Cell, 163(3): 759-771 (2015). 10.1016/j.cell.2015.09.038 Harrington...and Cas13 are 1). non-specific RNA cleavage and 2). cell toxicity. Cas7-11 does not display collateral ... Stem Cells Using Type I CRISPR-Cas. Molecular Cell, 74(5): 936-950.e5 (2019). 10.1016/j.molcel.2019.03.014...cleavage and is significantly less toxic to mammalian cells than Cas13 (likely due to the lack of collateral... -
Will You Be My Mentor? Finding and Asking for Mentoring Support
TypeBlog Post...article in the Addgene Blog Mentoring series will cover 2 of the 7 mentoring questions I set out to answer. ...101-Building Relationships for Success”. Choose 1-2 tactics to try. One of my favorites is making the ...Healthcare Businesswomen’s Association hosts an excellent group mentoring program in many of its chapters... -
Quick Guide to All Things Lentivirus
TypeBlog Post...PMC367857. 2. Naldini, Luigi, et al. "In vivo gene delivery and stable transduction of nondividing cells by a..., and the desired gene (transfer vector plasmid), 2) the HIV-1 genome containing all viral genes with ...protocols that have been described (protocol 1, protocol 2, protocol 3) to find the one that will give you the...-dividing cells. The ability to infect non-dividing cells is not restricted to in vitro cell culture as...target cells. If you are transducing non-adherent cells you might need to centrifuge your cells with the...favourite gene into your favourite cell line or into primary cells, this blog article will give you some...infect both dividing and non-dividing cells, including stem cells. These properties make lentiviral vectors... -
Antibodies 101: Conjugation
TypeBlog Post...residues, which can be found throughout the antibody. 2) Endogenous cysteines, such as those that make up ...Detecting antigens by quantitative immuno-PCR. Nat Protoc 2:1918–1930. https://doi.org/10.1038/nprot.2007.267 ...and Protein Modifications in Cells and Tissues in Situ. Curr Protoc Cell Biol 89:e115. https://doi.org... like proximity ligation, immuno-PCR, and single-cell applications (Hegazy, et al., 2020; Niemeyer, et...epitope and transcriptome measurement in single cells. Nat Methods 14:865–868. https://doi.org/10.1038... -
Hot Plasmids: Bacillus subtilis Libraries, iPSC Reprogramming, CRISPR Tools, & More!
TypeBlog Post...segment on the B. subtilis libraries. Hot Plasmid 2: Transcription factor fusions modulate iPSC reprogramming...Check out additional microbiology resources Stem cell models for disease and open science: Interview with... -
Plasmids 101: Using Transposons in the Lab
TypeBlog Post...somewhere else (Fig. 2). Class II TEs have LTRs on both of their ends. Figure 2: Overview of DNA...has four major components: 1) a CRISPR RNA (crRNA), 2) four proteins (TniQ, Cas8, Cas7, Cas6) that forms... yeast, plant, insect, and mammalian cells, including human cells. piggyBac is biased to integrate at ...is active in vertebrates and integrates in human cells at rates similar to retroviral vectors. The hyperactive...piggyBac has an integration efficiency in human cells similar to retroviral vectors. The hyperactive PB...transposase (hyPB) is ~10-fold more active in mammalian cells compared to the codon-optimized wild-type piggyBac...G/C)TNA. Tol2 can deliver 10-11 kB to mammalian cells without decreased efficiency, with a maximum cargo... -
Antibodies 101: Conventional vs Spectral Flow Cytometry
TypeBlog Post...from another within a fully stained sample. Figure 2 is an example of the emission spectra for two fluorophores...another during spectral unmixing. Figure 2: The full emission spectra for BV421 and BV711 on ...co-expression among cellular markers You’ll also need to know if markers are co-expressed in your cells when designing...immunologists, allowing for the rapid analysis of cell populations within a heterogenous tissue type, such...methods, the identification and isolation of rare cell types. In recent years, full spectrum flow cytometry...detector to detect one fluorophore and therefore one cellular marker. However, emission spectra of certain fluorophores...Spectral flow allows for autofluorescence extraction Cells produce a low level of fluorescence called autofluorescence... -
Plan Your Experiment
TypeCollection... or (2) a lack of efficient target cleavage in cells expressing both Cas9 and gRNA. Edited cells may be...expressed in your target cells. For easy-to-transfect cell types (e.g. HEK293 cells), transfection with standard... CRISPR machinery. For more difficult cells (e.g. primary cells), viral delivery of CRISPR reagents may...identify and enrich positive cells, or selection marker to generate stable cell lines (for details, see Plasmids...wide variety of mammalian cell lines Useful for difficult to transfect cell types, can also be used in...possible genotypes within the resulting cell population. Some cells may be wild type due to either (1) a ...will use the example of CRISPR/Cas9 in mammalian cells, many of these principles apply to using CRISPR ... -
Simple CRISPR-based Epigenetic Editing: dCas9-directed DNA Demethylation
TypeBlog Post...targeted DNA demethylation. Cell Discov 2, 16009. https://doi.org/10.1038/celldisc.2016.9. ...Hrit et al. 2018, Kaas et al. 2013). Figure 2: CRISPR TET-based epigenetic editing. In reality, ...its oxidized derivatives. Cell 152, 5 P1146-1159. https://doi.org/10.1016/j.cell.2013.02.004. Xu X, Tao...enzymatic activity cause demethylation? Dividing cells depend on DNA methyltransferase 1 (DNMT1) to copy...methylate sites blocked by dCas9. Within a few rounds of cell division, the original methylated strand is diluted...dCas9 expression and pLM-CMV-R-Cre. Selection for cells stably and highly expressing these constructs can...can be achieved by fluorescence-activated cell sorting, and stable gRNA expression can be achieved using... -
Plasmid-based Recombinant Monoclonal Antibodies: What They Are and Why You Should Be Excited About Them
TypeBlog Post...from animals or hybridomas. Figure 2: (Left) Figure 2: (Left) The light chain and heavy chain genes... be introduced into host cells, such as bacterial, yeast, or mammalian cells, for antibody production ...Nanobodies and recombinant binders in cell biology. Journal of Cell Biology 209:633–644 . https://doi.org...animals and bleed dates and even clonal hybridoma cell lines can produce more than one mAb (Bradbury et...plasmid or from an integrated sequence in a stable cell line. The genes encode the heavy chain and light...antibody protein binds an antigen. Image from Fvasconcellos. How are Recombinant Antibodies Made... -
Illuminating Epigenetics with A FRET Based Biosensor
TypeBlog Post...FRET signal back again. The Ting lab constructed 2 versions of this reporter to target the K9 (pcDNA3... 525.7570 (2015): 533-537. PubMed PMID: 26352475. 2. Bygren, Lars O., et al. "Change in paternal grandmothers...genes should be ‘read’ by the cellular machinery. This is how most cells in the body contain the same ...complex of DNA and histone proteins that compacts cellular DNA into chromosomes and reduces the risk of dangerous...the more compacted it becomes. This prevents the cellular machinery from physically interacting with the...visualise changes in histone methylation in living cells. Essentially this reporter construct consists of...recognise lysine 27 methylation. When tested in living cells where methylation of these sites was controlled,... -
Plasmids 101: Terminators and PolyA signals
TypeBlog Post...due to the presence of additional helper sequences (2-3). As alluded to above, termination and polyadenylation...and translation processes as well. Figure 2: The conserved eukaryotic polyadenylation signal directs...Plasmids designed to express genes in a given host cell type are generally broken down into two broad categories...purpose and mechanism of polyadenylation vary across cell types, but polyadenylation generally serves to promote... thought that poly(A)s are used to control the cellular concentration of regulatory RNAs and may additionally...additionally act as a quality control mechanism to rid the cell of mis-folded RNAs. Eukaryotic termination and polyadenylation...signal by using in vitro analyses. Molecular and Cellular Biology. 1992. PMID: 1333042. PubMed Central PMCID... -
7 Tips to Secure a STEAM Internship This Summer
TypeBlog Post...and scholarships in different subject areas! 2. Resume and cover letter know-how Tailor your resume...4. Letters of recommendation wisdom Reach out to 2-3 individuals in your professional circle to vouch...college. Prior to March 2020, internships were a fiercely competitive endeavor. Due to the COVID-19 pandemic... -
Form Your Own Peer Mentoring Group: A How-To Guide for Scientists
TypeBlog Post...The groups in these programs typically consist of 1-2 mentors and 3-5 mentees who meet together for an 8... together. If you all work at the same place, a 1-2 hour lunch on a regular schedule might work. If not...do once you are in a mentoring relationship. Celebrate your successes and support each other as you transition... -
28 Hot Plasmid Technologies from 2015
TypeBlog Post... Zetsche et al., Nat Biotechnol. 2015 Feb 2;33(2):139-42. doi: 10.1038/nbt.3149. Light-inducible ...and on your favourite signalling pathways (Figure 2). They are all available now at Addgene. 1 Lungu...20;19(4):507-17. 10.1016/j.chembiol.2012.02.006. 2 Guntas et al., Proc Natl Acad Sci USA 2015 Jan 6; ...Nihongaki et al., Chemistry and Biology. 2015 Feb 19; 22(2):169-74. High efficiency cloning for enzyme screening...inducible, gene knockdown with shRNA or shRNA-miR30, (2) tamoxifen-inducible CreERT2 gene deletion, (3) simultaneous...different fluorescent proteins, 8 constitutive promoters, 2 includible promoters, 3 polyA terminators and various...of plasmids required for each input/output system; 2) removing all chemically inducible promoters; 3) improving... -
5 Tips for Troubleshooting Viral Transductions
TypeBlog Post...Central PMCID: PMC3760253. 2. Rohwer, Forest. "Global phage diversity." Cell 113.2 (2003): 141. PubMed ... digest and compare it to some reliable controls. 2. Viral stocks may be sensitive to freeze thaw cycles...contaminating your transduction with the packaging cells. Packaging cell debris can be removed either by filtration... you can reduce the volume of cell culture medium on the packaging cells immediately following transfection...efficiency in cells that are sensitive to the toxicity of polybrene (e.g., hematopoietic or primary cells), and... the packaging cells after 1–3 days of selection. A lower percentage of surviving cells may be the result...adeno-associated virus transduction of cells." American Journal of Physiology-Cell Physiology 291.2 (2006): C386... -
Viral Vectors 101: Voltage Indicators
TypeBlog Post...Indicators GEVIs can be divided up structurally into 2 main groups: voltage sensitive domains and Rhodopsin...depending on your experimental system. Figure 2: General overview of chemigenetic tools. A genetically...Cellular communication and function depend on potential energy. Cellular activities like action potentials...Indicators As previously mentioned, cellular voltage is measured at the cell membrane, and this voltage is ...endocrine cells. It follows that the specific targeting of these voltage indicators needs to be cell type ...electrical events! Voltage indicators are voltmeters for cells! In this blog we will review how these indicators...related to the electrical impulse of the cardiac cells. To study this phenomenon you will likely want to... -
Fluorescent Proteins 101: Green Fluorescent Protein (GFP)
TypeBlog Post...from GFP and the mutation definitions found in Table 2 may not apply. Table 1: The specific mutations comprising..., V163A EBFP F64L, S65T, Y66H, Y145F Table 2: Functional role of specific mutations in GFP derivatives...measure, and control molecular signals, cells, and groups of cells in order to understand their activity...Fluorescence-activated cell sorting (FACS): This is a type of flow cytometry that separates mixtures of cells into distinct...Thus, FACS can be used to separate cells expressing GFP from cells that are not. Developmental/transgenic... localization profiles, acting as a biosensor or cell marker, studying protein-protein interactions, visualizing... was non-toxic and could be expressed in living cells, enabling the study of dynamic, physiological processes... -
Deep Dive: Fixing and Permeabilizing for Immunofluorescence
TypeBlog Post...membrane integrity (Fig. 2). For example, saponin interacts with cholesterol in cell membranes and leaves ... at too high a concentration. Figure 2: Examples of different permeabilization strategies...holes in the cell membranes of your sample to allow antibodies better access to intracellular targets. If...allowing antibodies into the cell where they could bind to intracellular epitopes. C) Permeabilizing with...method for visualizing molecules of interest within a cell or tissue. In that introduction, we broke down the...structure of your samples, the relationships between cellular components, and the accessibility of your target...cross-linkers work by (as the name suggests) cross-linking cellular proteins. Cross-linking is a chemical reaction... -
Google Forums Round Up: First Impressions of NgAgo
TypeBlog Post... PMID: 27136078. 2. Burgess, Shawn., et al. "Questions about NgAgo." Proteins & Cell (2016). 3. "NgAgo...engineering methods have their own pros and cons (2). The NgAgo DNA guide is inexpensive and can be 5’...degraded by the cellular machinery, leaving a small amount of active NgAgo/ssDNA complex in the cell. As proposed...results of Gao et al 2016 in a letter to Protein & Cell. Update (August 3rd, 2017) THE ORIGINAL NgAgo ARTICLE... guide, it cannot be produced from a plasmid in cells. Additionally, in vitro assembly of NgAgo/ssDNA ...dangerous, non-physiological temperature for mammalian cells and one which diminishes the endonuclease activity...guide. Therefore, researchers must co-transfect cells with 5’-P-ssDNA guides and an NgAgo expression plasmid... -
Chromoproteins: Colorful Proteins For Molecular Biology Experiments
TypeBlog Post...amilCP, tsPurple, and gfasPurple) (Figure 2). Figure 2: Chromoprotein expression from bacteria on... them into your cells, you can simply look for blue colonies to determine which cells have taken up the... that the cellular fitness cost varied greatly between chromoproteins. In some cases, cells containing... mScarlet as the donor in HeLa cells. Find ShadowR for mammalian cell expression here Now that you...cloning experiment worked just by looking at the cells on the plate. For example, if your plasmid contains...Here, the chromoprotein is expressed and gives the cell a magenta (amilCP) or purple (tsPurple) color. Though...added which induces expression of the toxin. Any cells that grow after this point will be those that have... -
Pooled Library Amplifications
TypeBlog Post...estimate transformation efficiency (Figure 2). Figure 2: Example of a serial dilution to estimate...Genome-wide Inhibition Library. DNA and cell amounts After deciding on a cell type, you will need to determine...DNA and how many cells to use for your transformation(s). The amount of competent cells you need total ... generally electroporated into electrocompetent cells to ensure the highest possible transformation efficiency...efficiency. Using Stbl4 or other ultra-high efficiency cells ensures that plasmid diversity in the library is...transformation may vary depending on the particular type of cells you are using, as well as other factors, such as...transformations, such as splitting 400 ng of DNA in 100 μL of cells over four individual electroporations. The specifics... -
CRISPR Activators: A Comparison Between dCas9-VP64, SAM, SunTag, VPR, and More!
TypeBlog Post...gene activation, with some genes experiencing around 2-fold activation levels. Although other methods have.... This method has been shown to activate genes at 2- to 3-fold higher than SAM, SunTag, and VPR (Zhou ...Control of Gene Expression. Cell 152:1173–1183 . https://doi.org/10.1016/j.cell.2013.02.022 Sajwan S, Mannervik...and Fluorescence Imaging. Cell 159:635–646 . https://doi.org/10.1016/j.cell.2014.09.039 Zhou H, Liu J,...from when looking to activate genes across diverse cell lines. dCas9-VP64 Description CRISPR activation...large and are not expressed consistently throughout cells. VPR Description VPR fuses a tripartite complex ...activation levels than SAM in some loci across Drosophila cell lines (Sajwan et al., 2019). SPH SPH combines components... -
Imaging Tools and Following a Passion for Basic Biology: Interview with Joachim Goεdhart
TypeBlog Post...Joachim ended up at the University of Amsterdam Chapter 2 - Joachim’s Academic and career goals. Career advice...Fluorescent Protein Plasmids 101: Visualizing Subcellular Structures and Organelles Resources at Addgene.org...Plasmids Find Plasmids for FRET Find Plasmids for Subcellular Localization ... -
Twenty Years of Sharing Science!
TypeBlog Post... anniversary! We've done so much in the past two (2!) decades that it's hard to summarize, but we wanted...into the Addgene website search bar? We'll be celebrating all year long, so keep an eye on our blog and... -
6 Tips for Grant Writing
TypeBlog Post...days before the deadline isn’t going to be much use. 2. Originality is essential for grant success The two... it’s important not to throw in the towel if 1 or 2 funding bodies say no. If possible, get feedback from...research (either because of expertise, equipment, or excellence of the institution). Likewise, if you’re staying...Cambridge University where he studied mechanisms of cell division. Recently Seán got the entrepreneurial ... -
PITChing MMEJ as an Alternative Route for Gene Editing
TypeBlog Post... PITCh vector via In-Fusion or SLIC cloning. Step 2: Design an insertion locus-specific gRNA The gRNA ...Find the plasmids from this publication at Addgene. 2. Dalvai, Mathieu, et al. (2015). “A Scalable Genome-Editing... for Mapping Multiprotein Complexes in Human Cells.” Cell Rep. 13: 621-633. PMID: 26456817. Find plasmids...Chromosomes). Using their PITCh plasmids, GFP knock-in cell lines can be created in about a month and a half...locus-specific gRNAs Step 4: Select for puromycin resistant cells Step 5: PCR amplify and sequence the locus to verify...crispr.mit.edu. They tested their system in HEK293 cells, integrating the GFP-Puro cassette into the FBL ... -
Plasmids 101: Degron Tags
TypeBlog Post...required components are 1) a SMASh-tagged protein and 2) asunaprevir (small molecule). dTAG The degradation...gone through an additional round of evolution (AID-2) to reduce some of the leakiness associated with the...uses a small molecule, a tag, and the endogenous cellular degradation machinery to function. The dTAG is...tag and small molecule. It does work in mammalian cells, mice, and even yeast, though (we have a kit!). ...and complete degradation of proteins in mammalian cells. Proc Natl Acad Sci U S A. 2012 Dec 4;109(49):E3350...Tags Plasmids for Endogenous Gene Tagging in Human Cells Antibodies 101: Epitope Tags ... -
With an Eye Towards the Future, We Look Back at the March for Science
TypeBlog Post...Vanderbilt University. She studies beta-cell function and failure in Type 2 Diabetes. Birmingham, AL, USA 33.5207...scientists have 1) the courage to make mistakes and 2) the integrity to recognize these mistakes quickly...available to people who want to join the dialog and 2) remember that science should not be partisan: everyone...of high profile people denying science, from celebrities falsely claiming vaccines cause autism to politicians...worried the march would be a simple, unquestioning celebration of science, at a time when scientists must rise...BC (Canada). She works in a lab that uses yeast cells to study how DNA damage promotes cancer. She is ... -
Better Dyeing Through Chemistry & Small Molecule Fluorophores
TypeBlog Post...26000849. 2. Grimm, Jonathan B., et al. "A general method to improve fluorophores for live-cell and single-molecule...expressed as a fusion with your favorite protein and (2) a synthetic fluorophore-contianing “ligand” that ...). These cell-permeable Janelia Fluor (JF) dyes have excellent properties inside living cells, especially... fluorescent proteins. In-cell labeling strategies The majority of in-cell labeling strategies have two...and oligonucleotide labels for fixed-cell imaging, not for live-cell applications. Thus, these fluorophores..."Imaging live-cell dynamics and structure at the single-molecule level." Molecular cell 58.4 (2015): 644...sparked a renaissance in biological imaging. Suddenly, cell biologists were no longer beholden to chemists and... -
Plasmids 101: Choosing an Antibiotic Resistance Gene
TypeBlog Post...suppress Zeocin-induced DNA cleavage in human cells. Mutagenesis, 20(2), 111–114. https://doi.org/10.1093/mutage...antibiotic selection. Essentially, this gene is a 2-in-1 providing both bacterial and eukaryotic selection...prevent cell death. One of the cool things about amp is that it's exclusively toxic to dividing cells. The... continuous cellular processes (e.g., protein synthesis), while amp only affects the cell wall synthesis...Check icon" %} Spectinomycin Excellent No Just bacteria Not SHuffle cells {% icon icon_set="fontawesome...icon" %} Zeocin Excellent No Bacteria, plants, and eukaryotes Not Tn5-containing cells {% icon icon_set..., penicillin, and is a beta-lactam that inhibits cell wall synthesis. The AmpR (amp resistance) gene produces... -
Fluorescent Proteins 101: Fluorescent Protein Timers
TypeBlog Post...linear region to solve for total expression time. 2. Timer functionality with a single gene Although it...290.5496 (2000): 1585-1588. PubMed PMID: 11090358. 2. Tsuboi, Takashi, et al. "Age-dependent preferential...to monitor cell, organelle, and protein localization. For instance, you might dye your cells and look at...either in whole cells or as a pool of fusion proteins localized to a specific region of the cell. For example...the relationship between the age of a cell, protein, or cellular structure and a particular biological...trafficking to a subcellular location, start of gene expression, development of a cell structure, etc)....timers, researchers can look at a single image of a cell and understand how protein localization changes ... -
Antibodies 101: Producing Recombinant Antibodies
TypeBlog Post...detection, and control. Int J Pharm. 2018 Oct 25;550(1-2):251-268. doi: 10.1016/j.ijpharm.2018.08.043. Epub...and particle formation. J Pharm Sci. 2015 Feb;104(2):602-11. doi: 10.1002/jps.24259. Epub 2014 Nov 21....and yeast cells are cost-effective and faster-growing than mammalian cells, but mammalian cells can perform...your cells with your plasmid(s), and then wait 7-14 days (in mammalian cells) to collect the cell culture...production system, cell lines typically used include Human Embryonic Kidney (HEK) cells and Chinese Hamster...recombinant antibodies with some molecular biology and cell culture experience. Let’s go over the basics of ... place in bacterial, yeast, plant, or mammalian cells. Each of these systems has their advantages and ... -
New Tools Enable CRISPRa for Neuroscience Applications
TypeBlog Post...with neuron-specific expression of dCas9-VPR (Figure 2), a popular Cas9 activator developed by the Church...ubiquitous ones such as EF-1α and CAG. Figure 2: Dual lentivirus system with ubiquitous expression...fluorescence activated cell sorting (FACS) to isolate differentiated from undifferentiated cells at the end of ...these cell types are used. The lack of good flow cytometric antibodies for many CNS-resident cell types...that drive neuronal fate and reprogramming." Cell stem cell 23.5 (2018): 758-771. PubMed PMID: 30318302...CRISPRa screening approach in embryonic stem (ES) cells to determine which transcription factors promote...antibodies, downstream of the TUJ1 coding sequence. ES cells that stably express the dCas9-Suntag activator were... -
Zhang Lab's CRISPR Frequently Asked Questions
TypeCollection...extraction solution, runs the protocol, then uses around 2-4ul in each 50ul PCR reaction. The gDNA extracted ...find both single-allelic and bi-allelic cells. Single-allelic cells usually make up the majority in culture...specificity. A good reference is this Cell paper: http://www.cell.com/abstract/S0092-8674(13)01015-5 As for.... A good example/reference is this Cell paper: http://www.cell.com/abstract/S0092-8674(13)01016-7 In the...allows you to sort for GFP-positive cells and to enrich for those cells that were positively transfected....CRISPR is used to engineer a locus, isolate single cell colonies, then genotype them, it is possible to ...or delivery the two plasmids together into your cells. If you want to use double nickase, you need to ... -
Tips for Screening with Yeast Two Hybrid Systems
TypeBlog Post...retain their individual activities when separated (2), and that DBD and TAs from different systems could... Enzymol. 1983;100:293-308. PubMed PMID: 6312261. 2. Keegan, L., Gill, G., and Ptashne, M. Separation ...entire proteome of a particular cell type, or a subset based on a cellular compartment or growth stage)....extensively to screen for molecular interactions in the cell, including protein-protein, protein-DNA and protein-RNA...field of eukaryotic transcriptional activation and cell biology. During this period, proteins were successfully...The reporter gene then allows detection of those cells where binding between the proteins of interest has...alternative fungi (C. albicans, pC2HB) (7) and mammalian cells. If the problem is that your proteins are not post-translationally... -
Getting to Know Expansion Microscopy
TypeBlog Post...maybe label) your sample (i.e. cultured cells or tissues). Step 2: attach anchors to your sample that will...quite so much. Created with biorender.com Steps 2-4 are not found in standard IHC/ICC protocols and ... for EM is not something you find in the average cell and molecular biology lab, and EM is limited in ...ultrastructural relationships that influence everything from cell division to memory, but don’t have access to the...properties of the sample itself. For example, cultured cells are typically easier to expand than mouse brain ..., Mohar B, Eddison M, et al (2022) Visualizing cellular and tissue ultrastructure using Ten-fold Robust... Zwettler FU, Guennec ML, et al (2019) Imaging cellular ultrastructures using expansion microscopy (U-...