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We narrowed to 672 results for: abo.1

Showing: 101 - 120 of 672 results
  1. Controlling for Off-target Effects with a New Genome-wide CRISPR Screen Design

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    Blog Post
    ...holds true in genome-wide screens.   Figure 1: Summary of the advantages of the new approach to ... in both screens, with the growth screen having a 1% false discovery rate and identifying >88% of previously...in Morgens et al. contains three types of guides: 1) targeting guides (blue), which target all protein-coding...off-target sites was profiled. Guides with exact or 1-bp mismatch off-targets had greater toxicity than ...characteristics that influence gRNA off-target activity: 1) mismatches closer to the PAM are less tolerated than.... When comparing the toxicity of guides that have 1-bp mismatch off-target sites, short guides had reduced...Knockout Library are available from Addgene! References 1. Morgens, David W., et al. "Genome-scale measurement...
  2. Celebrating Outstanding CRISPR/Cas9 Achievements at the Dr. Paul Janssen Award Dinner

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    Blog Post
    ...minutes, which was fun to watch. A simpler 1 protein - 1 RNA system Drs. Dounda and Charpentier met at...to direct cleavage the result was a simpler 1 protein - 1 RNA system.  Dr. Charpentier advocated for the...be used in people until we learn more about safety and more about the how to use genome edited stem cells...because Jennifer did her graduate work one floor above mine in the lab of Dr. Jack Szostak, who went on...ceremony honored Charpentier and Doudna, who talked about their research leading up to the discovery of the... at a 2011 conference and decided to collaborate on what was a “curiosity” driven project. Both awardees...importance of the strong, cross-disciplinary collaboration they shared to the work they did together. They...
  3. Fluorescent Tagging of Endogenous Genes with SapTrap

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    Blog Post
    ... 5’ and 3’ homology arm repair template (Fig. 1, Step 1). There is no need for PCR or cloning, as digestion...selectable marker, and connector to be released (Fig. 1, Step 2-3). Since donor plasmids of the same type ...correctly assembles the final targeting vector (Fig. 1, Step 4), and co-injection of the targeting vector...human cells. To use CRISPaint, users need 3 vectors:  1) a gRNA vector that targets the gene of interest, ... Tagging with Short Homology Donors.” Cell Rep.15(1) (2016):210-8. PubMed PMID: 27052166. Kunzelmann,...tagged gene. Most insertions can only be detected by labor-intensive processes like PCR or by evaluating visual...repair after a CRISPR/Cas9 induced break. Learn more about these constructs and the cell lines they’ve been...
  4. Plasmids 101: TOPO Cloning

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    Blog Post
    ... mind that Taq polymerase has an error rate of about 1 in 3,500 bases. Typically polymerases with proofreading... strand and a tyrosyl residue of topoisomerase I (1). If a 5′ hydroxyl group from a different DNA strand...Let’s break down the steps needed for TOPO cloning: 1. Create Your PCR Product: Design standard primers ...enzyme and Taq, with Taq used in an excess ratio of 10:1. Gel purify your PCR product and incubate it with ...you to see colonies within 8 hours. References: 1. Shuman S. "Recombination mediated by vaccinia virus...
  5. Plasmids 101: Control Plasmids

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    Blog Post
    ...from a plasmid   Figure 1: Expression Level of Gene X The results shown above are from a single experiment...Referring back to the experiment associated with Figure 1, the independent variable is the shRNA. Therefore ...the protein.   In analysis of the result in Figure 1, an internal control, such as the GFP-expressing Plasmid...control and is consistent with the result in Figure 1 could look like this: Figure 2: Expression of Plasmid...plasmid.  Let us now revisit our experiment. In Figure 1, it appeared as though the shRNA did not knock down...scientific inquiry and investigation. References: 1. The problem of pseudoreplication in neuroscientific...optimization within your experiment. Read on to learn more about the various controls that can be used for plasmid-based...
  6. An Interview with Connie Cepko - Gene Therapy, Plasmid Tools and Insights to Success

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    Blog Post
    ... Podcast breakdown: (Time : Topic) 0:00-1:00 : Introduction 1:01-9:04 : What got Professor Cepko Interested... producer for the Addgene Podcast.     References 1.Tang, Jonathan C.Y., et al. “A nanobody-based system... Cepko. Listen to the podcast below to hear all about the research being conducted in Professor Cepko'...and mentoring styles. If you'd like to learn more about Professor Cepko's recent work on developing GFP-...the time to talk to us and look forward to hear about more exciting discoveries from her lab. Special ...
  7. Droplet Digital PCR for AAV Quantitation

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    Blog Post
    ...range of titers. We usually dilute our samples 1:6 million to 1:25 million.  After making the dilutions, they...note that the dynamic range of the ddPCR is between 1 and 100,000 genome copies (GC) per reaction. Since...In the image to the right, there is approximately 1 positive copy per microliter in the no template control...elongation time to 2 minutes and the denaturation time to 1 minute has been shown to increase droplet separation...diagnosis." Emerging microbes & infections 7.1 (2018): 1-9. PubMed PMID: 29691363. PubMed Central PMCID: PMC5915492... droplet generator, you will have to be careful about transferring your droplets from the droplet generator...Additional resources on the Addgene blog Read more about polymerase chain reaction Browse our blog posts ...
  8. CRISPR Antimicrobials

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    Blog Post
    ..., they used 1-2 CRISPR crRNAs targeting sequences found only in certain bacteria (Figure 1). Citorik et...from 50% to 11% in just 24 hours.   Figure 1: Single-phage strategies for bacterial CRISPR targeting...genome, and it carries CRISPR machinery targeting 1) the given resistance gene and 2) a second lytic phage...the fight against bacterial superbugs. References 1. Citorik, Robert J., Mimee, Mark, and Timothy K. Lu...Targeted Bacterial Population Editing.” Cell Syst. 1(3):187-196. (2015). PubMed: PMID 26973885. Additional...organizations are working to help educate the public about proper antibiotic usage. Although these steps are...laudable, they likely won’t solve the growing problem. Above all, we need new antimicrobials, ideally ones for...
  9. Optogenetics Guide

    Type
    Guide
    ...algae Chlamydomonas reinhardtii . Channelrhodopsin-1 (ChR1) is excited by blue light and permits nonspecific...based on the LOV2 domain of Avena sativa phototropin 1 LOVETRAP reversibly sequester and release proteins...concept of optogenetics. 2012 Prog Brain Res. 196: 1-28. PMID 22341318 Gradinaru V, Zhang F, Ramakrishnan...diversifying and extending optogenetics. Cell. 196:1-28. PMID 20303157 Han X, Boyden ES. 2007 Multiple-...Limitations and Future Developments. Exp Physiol. 96(1): 19–25. PMID 20621963 Mattis J, Tye KM, Ferenczi ... to permit CIB1 binding. As shown in the figure above, this light induced binding can be utilized to control...dimerization. In addition to the applications described above, both LOV and Dronpa can control activity of a fused...
  10. AAV Titers: Where Do They Come From And What Do They Mean?

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    Blog Post
    ...near-perfect physical-to-infectious particle ratio of 1:1 (Zeltner et al., 2010). However, for recombinant ...preparations are genome-containing (Figure 1).    Figure 1: Electron micrograph of an Addgene AAV...reported a physical-to-infectious particle ratio of 50:1 (Zeltner et al., 2010). The specific infectivity of... lot (if we still have it available). References 1. Fagone, Paolo, et al. "Systemic errors in quantitative... Human Gene Therapy, Part B: Methods 23.1 (2011): 1-7. PubMed PMID: 22428975. PubMed Central PMCID: PMC3640491... Addgene.org Find All Available AAV Learn More about Virus Production Find Viral Vector Protocols ...
  11. SciComm with the Experts at Science in the News Part 1

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    Blog Post
    ...they think about communicating science. Listen to the interview with Science in the News, Part 1 Podcast...Communication The Purpose of Science Communication #1 Mistake Scientists Make when Communicating with Non-Scientists...supporters of science communication. To help you think about ways to effectively communicate your science, we...Interview with Science Rapper Tom McFadden Learn about SITN's work at DayCon 2015 5 Reasons to Use Reddit...
  12. High Complexity Golden Gate Assembly with NEB’s DAD

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    Blog Post
    ...reactions. (Need a refresher? The five rules are: (1) don’t use the same overhang twice; (2) avoid palindromes...Gate) pot (Pryor et al., 2022).     Figure 1: Workflow for high complexity Golden Gate Assemblies...different enzymes and cycling conditions (see Table 1).   Enzyme Temperature Incubation time/cycling...cycling Overhang length T4 DNA ligase 25 °C 1 hour 3-base or 4-base T4 DNA ligase 25 °C ...hours 3-base or 4-base T4 DNA ligase 37 °C 1 hour 3-base or 4-base T4 DNA ligase 37 °C ...Ligase MM 37-16 °C cycling 3-base Table 1: Enzyme and cycling conditions available in DAD tools...cycling. The Pros and Cons Researchers used the tools above to complete a 52-piece assembly of a 40 kb T7 phage...
  13. Plasmids 101: Gateway Cloning

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    Blog Post
    ...recombination sites (attL-left- and attR-right-, Figure 1). Under certain conditions, the attL and attR sites...regeneration of attP and attB sites.   Figure 1: Lambda phage integration and excision reactions. ...expression of the human KRAS gene in mammalian cells. STEP 1: Generate an Entry Clone There are a few different...could use a vector like pLenti CMV Puro DEST (w118-1) or the doxycycline-inducible pLIX_403. The chosen...the generation of the expression construct in only 1 day, as opposed to 2+ days with traditional restriction... Find Gateway cloning plasmids here! References 1. Chee JY, Chin CF (2015) Gateway Cloning Technology... expression systems. Keep reading to learn more about the Gateway cloning method and its advantages. An...
  14. Some Like it Hot: Thermostable GeoCas9

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    Blog Post
    ...Cells? Yes Yes Longevity in Serum?* No Yes Table 1. Comparing SpCas9 and GeoCas9. *For in vitro Cas9 ...GeoCas9 is active at high temperatures Figure 1: Thermostability of SpCas9 vs GeoCas9. SpCas9 or GeoCas9...from 25-80 °C. Activity is expressed as Kcleave (min-1). SpCas9 has maximum activity from 35-45 °C, while...outperformed SpCas9 at high temperatures. See Figure 1 for a summary of the experimental results. GeoCas9..., see the table below and read on to learn more about GeoCas9.   SpCas9 GeoCas9 Size 1368 AA 1087...vivo. What aspect of GeoCas9 are you most excited about? Thermostability? Longevity in human plasma? Something... Additional Resources on the Addgene Blog Read about CRISPR Methods for Bacterial Genome Engineering   ...
  15. Quick Guide to All Things Lentivirus

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    Blog Post
    ...family including human immunodeficiency virus type-1 (HIV-1), can infect both dividing and non-dividing cells...have been devoted to develop efficient and safe HIV-1-derived lentiviral vectors due to their ability to...lentiviral vectors consisted of three plasmids encoding 1) the lentiviral vector genome which was composed of...desired gene (transfer vector plasmid), 2) the HIV-1 genome containing all viral genes with the exception...generation because this vector requires only three HIV-1 genes (gag, pol, and rev) for production. Third generation...several protocols that have been described (protocol 1, protocol 2, protocol 3) to find the one that will...to additional protocols and plasmids.  References 1. Miller, A. DUSTY, and C. A. R. O. L. Buttimore. "...
  16. Plasmids 101: FLEx Vectors

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    Blog Post
    ...coding sequence in the antisense orientation (Figure 1, top). The entire DNA cassette would be flanked by...include both Cre and FLP recombinases.   Figure 1 (modified from Schnutgen et al. Nat Biotech 2003):...identical sites on one end of the DNA fragment (Figure 1, middle). A second recombination event then excises...between the identical loxP or lox511 sites (Figure 1, bottom). Since only one loxP and lox511 site will...genOway press release for more information. References: 1. Schnütgen F, Doerflinger N, Calléja C, Wendling O... Blog  Read about Other Means of Genome Engineering Using FLEx AAV Vectors? Learn about Viral Vector ...12665802. 2. Branda, CS and Dymecki, SM. Talking about a Revolution: The Impact of Site-Specific Recombinases...
  17. Pathways Over Time Plasmids Engage Students in Functional Genomics Research

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    Blog Post
    ...public. You can find out more about Clare at the Biology Dept. site.  References 1. American Association for...authentic research experiences to undergraduate students (1, 2), but educators face significant challenges in ...6). Methionine synthesis in S. cerevisiae (Figure 1) occurs through a well-characterized pathway with ...sequences for ten different MET/Met genes (Figure 1) from the two yeast species into the pYES2.1/V5-His...selected from different parts of the Met pathway (Fig. 1). In addition to the complementation experiments that...Addgene Blog Learn about Synthetic Biology with BioBuilder Use Addgene Videos to Learn about Basic Lab Techniques...species, but these studies generally leave questions about gene function wide open. What if two seemingly similar...
  18. Viral Vectors 101: What is a Virus (and a Viral Vector)?

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    Blog Post
    ... an envelope are called enveloped viruses (Figure 1). Like bacteria, only a tiny fraction of viruses are...are pathogenic (Balloux & van Dorp, 2017). Figure 1: A non-enveloped virus (left) and an enveloped virus...create far safer viral vectors that can be used in BSL-1 or BSL-2 labs. Viral vectors are viruses that have... https://doi.org/10.1016/B978-0-12-800947-5.00004-1 Taylor, M. W. (2014). What Is a Virus? In M. W. Taylor... using biorender.com   If you’re new to talking about viruses, here’s a quick tip on terminology. “Virus...have a growing number of Viral Vectors 101 posts about each type, so be sure to check our blog, or our ...
  19. Multiplex Genome Editing with CRISPR-Cpf1

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    Blog Post
    ...For these experiments, cells were infected with a 1:1 ratio of two AAVs,  one expressing Cpf1 and the other...or thoughts about Cpf1 multiplexing, leave them in the comments below.        References 1. Zetsche et...comparison of Cpf1 vs. Cas9, see the table below. Table 1. Comparing the Cas9 and Cpf1 CRISPR Nucleases   ...Overall, these approaches have two main drawbacks: 1) Most rely on transfection of more than one vector...targets compared to Cas9.  Read on to learn more about Cpf1 multiplexing.  For an in-depth review of Cpf1...
  20. Twenty Years of Sharing: Expanding Accessibility

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    Blog Post
    ...our repository to an amazing 111 countries (Figure 1)! But while we were making the materials available...accessibility varied country to country.   Figure 1: Number of countries Addgene distributes to per year...date, we have partnered with six distributors (Table 1), in China, Korea, Japan, Brazil, India, and Mexico...material is right for their experiment.     Table 1: Most popular guides, protocols, and collections of...in 2023, from visitors in 218 countries. In Table 1, you can see our most popular educational resources... execute a step can provide needed clarity (Table 1). Our most popular video, however, is “What is a Plasmid...a less tangible form: knowledge and information about the materials in our repository. We started to increase...
Showing: 101 - 120 of 672 results