Skip to main content
Addgene
Showing: 51 - 100 of 597 results
  1. CRISPR-based Genome Editing Systems For Editing in E. coli

    Type
    Blog Post
    Published
    April 13, 2021, 1:15 p.m.
    ... Then plasmids are cured from the cell. Steps 1-1 and 1-2 can be done simultaneously. Image from Li et...coli K-12 strains, 2 E. coli B strains, 1 E. coli W strain, and 1 Tatumella citrea, with a total of 70 sites... update the pCas/pTargetF system.   Figure 1: The editing process begins with the addition of the...updates involved the following changes. In pCas9, we 1) replaced the promoter of gRNA-pMB1 with PrhaB, 2)...biosynthesis, we constructed a strain library with 1-11 copies of integrated genes. We obtained a stable...far, we’ve used the MUCICAT system in two ways: In our initial paper, we used MUCICAT to optimize the gene...industrial strain. Not only is MUCICAT better, it is faster. Using MUCICAT only needs 2 newly constructed...
  2. New Neuroscience Tool: The iGluSnFR3 Glutamate Sensor

    Type
    Blog Post
    Published
    April 7, 2022, 1:15 p.m.
    ...sensing glutamate using both 1-photon and 2-photon imaging.   Figure 1: 1P and 2P excitation and ...hSynap: Human Synapsin-1 promoter. Good for neuronal expression. hSynap-FLEX: Synapsin-1 promoter, FLEXed for... v857. Image adapted from Aggarwal et al., Figure 1   Increased versatility through two different...expression in Cre-expressing cells. hSynap-FLP: Synapsin-1 promoter, FLP-dependent expression GFAP: Glial fibrillary...Glutamate plays a variety of roles in synaptic communication and can trigger other forms of neuronal signaling...SF-Venus-iGluSnFR). iGluSnFR3: Improved Glutamate Indicators for Synaptic Imaging However, the first two generations... 30377363 Aggarwal, Abhi, et al. . “Glutamate indicators with improved activation kinetics and localiation...
  3. CRISPR-mediated Plant Base Editors

    Type
    Blog Post
    Published
    Jan. 3, 2019, 1:35 p.m.
    ...excision repair mediated by uracil glycosylase (Figure 1). The presence of a uracil glycosylase inhibitor (...generation of the desired T-A base pair. Figure 1: Transition mutation (C>T, G>A, A>G, and T>C) installation... A-T base pair is converted to a G-C pair (Figure 1). As the cellular inosine excision repair is not as...Target-AID based (CBE-2)-  and rAPOBEC based (CBE-1)-  CBEs are successful base editors in rice, tomato...deaminase can edit in a stretched window ranging from 1-17 bp relative to the PAM sequence (Zong et al., 2018...which recognize PAM sequences other than NGG (Table-1). Type Nickase Cas9 (D10A) Deaminase PAM requirements...locus/loci, choose a base editor variant from Table 1 depending on the PAM sequence. Avoid targeting a ‘...
  4. An Integrin Antibody Toolkit from IPI

    Type
    Blog Post
    Published
    March 28, 2024, 1:15 p.m.
    ...-Integrin alpha 5 beta 1 [IPI-ITGA5/ITGB1.2] Integrin alpha-5,Integrin beta-1 Human, Mouse IgG1 Rabbit...-Integrin alpha 5 beta 1 [IPI-ITGA5/ITGB1.4] Integrin alpha-5,Integrin beta-1 Human, Mouse IgG1 Rabbit...subtype-specific β1 integrin mechanics. Nature Communications, 13(1), 7471. https://doi.org/10.1038/s41467-022...specific integrins in cellular processes.   Figure 1: Integrins can shape into three conformations: (A)...immunoprecipitation and immunohistochemistry. Table 1: IPI antibodies  Antibody Target Proteins Reactivity...Human IgG1 Rabbit Anti-Integrin alpha M [IPI-LM2/1] Integrin alpha-M Human IgG1 Rabbit Anti-Integrin...Human IgG2a Mouse Anti-Integrin alpha M [IPI-LM2/1] Integrin alpha-M Human IgG2a Mouse Anti-Integrin...
  5. Hot Plasmids February 2024

    Type
    Blog Post
    Published
    Feb. 20, 2024, 2:45 p.m.
    ...Biotechnology, 10.1038/s41587-023-01756-1. https://doi.org/10.1038/s41587-023-01756-1. PMID: 37095348. Breaking...molecular fusion and membrane-targeting applications. Nature Methods, 1–9. https://doi.org/10.1038/s41592-023...rodents and broad tropism in primates. Nature Communications, 14(1), 3345. https://doi.org/10.1038/s41467-023...incubation, even with multiplexed guides. Figure 1: A) Cell-penetrating Cas9, fused to HIV TAT, Myc and...expressing COX8a-mStayGold. Scale bars 10 μm (main), 1 μm (inset). Image reused from Ando et al. 2023, under...StayGold fluorescent protein. Nature Biotechnology, 1–4. https://doi.org/10.1038/s41587-023-02018-w. PMID..., its dimeric nature can interfere with some applications. Several labs have been working to produce monomeric...
  6. FastCloning: A Newer, Simpler Cloning Technique

    Type
    Blog Post
    Published
    Nov. 1, 2016, 2:30 p.m.
    ...to the most colonies after transformation. When a 1:1 vector:insert ratio is used in the DpnI digestion... get tips for applying it in your own lab. Table 1: Comparison Between Standard Restriction Cloning and...Connecticut interested in protein science.     References: 1. Celie, Patrick HN, Annabel HA Parret, and Anastassis...PCR cloning method." BMC biotechnology 11.1 (2011): 1. PubMed PMID: 21992524. PubMed Central PMCID: PMC3207894...Restriction Enzymes + - PCR Amplification + + Digestion + + Gel Purification + - Ligation + - Transformation...vector is located in the 3’ end of the multi-cloning site, and the reverse primer is located in the 5’...Molecular cloning is the isolation, insertion and amplification of a recombinant DNA without sequence alteration...
  7. Addgene is Expanding Our Viral Vector Service!

    Type
    Blog Post
    Published
    Oct. 15, 2024, 1:15 p.m.
    ...  Request review: 1–2 days Prep and QC completed: 6–8 weeks Average shipping time: 1–2 days (USA); 3–4...choice of five different serotypes.   Figure 1: The process of requesting and ordering a Packaged...request in three different quantities: 10x 100 µL (1 mL), 25x 100 µL (2.5 mL), or 50x 100 µL (5 mL).  Once...with our production process. This process will take 1–2 days, and we anticipate approving the vast majority...request is approved, you will receive an email notification that your request is ready to order. An “Add...subscribe to the Addgene blog for updates and educational resources.  We hope you’re as excited about this...
  8. Deep Mutational Scanning with One Pot Saturation Mutagenesis

    Type
    Blog Post
    Published
    Feb. 22, 2017, 3:30 p.m.
    ...created by making some or all of the following modifications: 1) increased concentration of Taq polymerase...introduced, and scalability (see Supplementary Table 1 of Wrenbeck et al). It uses a uracil labeled wild-...primers to introduce all desired codon changes (step 1 in the image above). A second universal primer is ...strand is nicked by the BbvCI variant not used in step 1. Then this strand is degraded with ExoIII and ExoI...number of positive clones. See Supplementary Note 1 in Wrenbeck et al for details on how nicking was optimized... strand of DNA degraded in the first digest (step 1 in above diagram). Remember that the BbvCI enzymes...time no, but there are 2 instances where it does. 1) When the backbone vector has multiple BbvCI sites...
  9. Cancer, Inflammation and Immunity - Harnessing the Body’s Defenses to Fight Cancer

    Type
    Blog Post
    Published
    July 6, 2017, 1:59 p.m.
    ...aggregation, and potentiates the effect of PD-1 blockade.“ (Ref 4). PD-1 helps tumor cells evade the immune system...fasting has a positive effect on cancer treatment (Ref 1). As described in the presentation, starvation or ...of the immunosuppressive cell surface receptor PD-1. This immunosuppressive environment in turn may represent...  (Chimeric Antigen Receptors) CAR T cells and PD-1 modulators. An exciting development in immunotherapy...free deposit and distribution service! References: 1. Pietrocola, Federico, et al. "Caloric restriction...Immunosurveillance and Defense With increasingly sophisticated visualization techniques it is possible to follow...
  10. Quickest Way to Deposit Plasmids: The Deposit Spreadsheet

    Type
    Blog Post
    Published
    March 8, 2017, 3:15 p.m.
    ...complete Step 1. Steps 2 and 3 are usually very easy — our tech transfer team will communicate with your ...scientist, you will have the most involvement with Step 1, and, while data entry can be a chore, we’ve made ...Deposit” and “Download Deposit Spreadsheet” (see Figure 1). Please read our “How to Deposit Your Plasmids with...thorough guide to our online data entry process. Figure 1: Begin the deposit process by clicking “Submit Online...spreadsheet (Figure 2) and are described in Table 1. Some cells have drop-down options for you to choose...and are exceptions to our standard workflow.  Table 1: Guidelines for the data fields in the deposit spreadsheet...species can be indicated in the “Species Other” column. Relevant Mutations Indicate the amino acid...
  11. Plasmids 101: TOPO Cloning

    Type
    Blog Post
    Published
    Oct. 27, 2016, 2:30 p.m.
    ... 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 ...mind that Taq polymerase has an error rate of about 1 in 3,500 bases. Typically polymerases with proofreading...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...insert comes from using Taq polymerase for the amplification step since Taq polymerase leaves a single deoxyadenosine...rejoining supercoiled DNA ends to facilitate replication. The TOPO technique specifically uses Vaccinia...
  12. Antibodies 101: Designing Your First Flow Panel

    Type
    Blog Post
    Published
    May 28, 2024, 1:45 p.m.
    ...marker. Looking at Table 1, we can recognize a couple of fluorophores from Figure 1. For example, the chart...efficient (i.e., happen most of the time). Figure 1 shows a graph from the BDŽ Spectrum Viewer, outlining...Resonance Energy Transfer (FRET).   Figure 1: Emission spectra and respective colors of a few commonly... the brightness of individual fluorophores. Table 1 describes the brightness of a few commonly used fluorophores...Brighter fluorophores have a stronger signal. Table 1: Degrees of brightness for a few commonly used fluorophores...blue laser excites at a wavelength of 488 nm (Table 1), which is near a local maximum of PE's excitation...Knowing that the red laser excites at 640 nm (Table 1), while comparing the two fluorophore's excitation...
  13. AAV Titers: Where Do They Come From And What Do They Mean?

    Type
    Blog Post
    Published
    Nov. 15, 2017, 3 p.m.
    ...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...the other to guess a category by listing off things that fall into that category? Okay, let’s play. I’...’ll list the examples and you try to guess the category: ELISA...qPCR...Digital droplet PCR...DNA dot ...
  14. Scientific Reproducibility - Focusing on Solutions at the Minisymposium on Reproducibility

    Type
    Blog Post
    Published
    May 18, 2018, 7:32 p.m.
    ... handed out at the event). Program 0 - 1:24 - Intro 1:24 - 29:31 - Reproducibility Overview - Jeffrey... 49:45 0 1:18:45 - Reagent Development - Steven C. Almo, Institute for Protein Innovation  1:18:45 - 2...reproducibility As Jeffrey Flier points out in his talk (1:24 - 29:31), there are a variety of ways of defining...enterprise towards greater reproducibility. Cause 1: Inability to repeat previously performed experiments...the Institute for Protein Innovation (IPI) (49:45 - 1:18:45), there are also initiatives to create more ...found. Consider the hypothetical situation in Figure 1 where many scientists are performing similar experiments...someone has replicated it precisely. You can find a great discussion of different types of replication in Nosek...
  15. 5 Uncommon Ways to Gain Career Skills During an Uncommon Time

    Type
    Blog Post
    Published
    Oct. 20, 2020, 1:15 p.m.
    ...need a job. Start now. Informational interviews are 1:1 discussions with someone who has interesting experiences...conversation builds a relationship for the future and the 1:1 format is good for everyone including those that ...out-of-the-box ideas that might jump start your learning. 1. Create a peer mentoring group We don’t all get the...be a time when you need to speak publicly to communicate your work. One of my 10 tips for giving a great...; Graduate Student Funding Opportunities Open Education Database: 100 Places to Find Funding For Your ...
  16. A Primer on Optogenetics: Introduction and Opsin Delivery

    Type
    Blog Post
    Published
    Sept. 10, 2015, 2:30 p.m.
    ...Jacqueline N Crawley  [et al]. 2012;Chapter 1:Unit 1 20 1-18. doi: 10.1002/0471142301.ns0120s59. PMID:...mutually exclusive) commonly used in optogenetics: 1) electrophysiology and 2) behavioral experiments. ...can be broken down broadly into three main steps: 1) Selection and expression of your opsin of choice ...reviews for a discussion of the different variants [1, 2, 4]. And, of course, the best way to learn about...monitor expression at various time points (e.g. every 1-2 weeks over 8 weeks) in order to determine the optimal...follow him on Twitter @derekpsimonphd.    References 1. Tye KM, Deisseroth K. Optogenetic investigation of..., Jacqueline N Crawley  [et al]. 2013;4(435):4 35 1-4  20. doi: 10.1002/0471142301.ns0435s65. PMID: 25429312...
  17. REPLACR Mutagenesis: Replacing In Vitro Recombination Methods

    Type
    Blog Post
    Published
    Feb. 10, 2016, 3:30 p.m.
    ...deletions, point mutations PCR Reactions 1 1 1 per fragment 1 per fragment In vitro Assembly No No Yes...methods for site directed mutagenesis   References 1. Trehan, Ashutosh, et al. (2016). “REPLACR-mutagenesis... the steps of gel purification and in vitro recombination. Across all modifications described in Trehan...mutations, large deletions/insertions require complicated, often costly in vitro assembly methods. A new...recombination machinery, which facilitates easy genetic modification by homologous recombination. In most recombineering...
  18. Controlling for Off-target Effects with a New Genome-wide CRISPR Screen Design

    Type
    Blog Post
    Published
    Sept. 13, 2018, 1:55 p.m.
    ...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...
  19. Plasmids 101: Control Plasmids

    Type
    Blog Post
    Published
    April 9, 2015, 3:29 p.m.
    ... and investigation. References: 1. The problem of pseudoreplication in neuroscientific studies: is it...Gene X using shRNA expressed from a plasmid   Figure 1: Expression Level of Gene X The results shown above...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...two types of replicate controls: technical and biological. In general, technical replicates can be thought...
  20. Celebrating Outstanding CRISPR/Cas9 Achievements at the Dr. Paul Janssen Award Dinner

    Type
    Blog Post
    Published
    Sept. 15, 2014, 6:05 p.m.
    ...the result was a simpler 1 protein - 1 RNA system.  Dr. Charpentier advocated for the crucial role of ...minutes, which was fun to watch. A simpler 1 protein - 1 RNA system Drs. Dounda and Charpentier met at...adaptive bacterial immunity and its potential applications in rewriting the genome. Their award acceptance... same Polish sub-dialect making their Skype communications extra fun) who shared first authorship on their... area will accelerate the launch of clinical applications. During the panel discussion, Dr. Mello took...for billions of years (…) Bacteria are really sophisticated”.     New to CRISPR/Cas9 Technology? Learn ...
  21. Antibodies 101: Producing Recombinant Antibodies

    Type
    Blog Post
    Published
    Aug. 13, 2024, 1:15 p.m.
    ...materials have been washed away (Figure 1).      Figure 1: The steps of rAb production. Created ...EBNA1 Cells. Methods Mol Biol. 2018;1850:1-16. doi: 10.1007/978-1-4939-8730-6_1. PMID: 30242676. Frenzel...Neuroscience Research. Curr Protoc Neurosci. 2020 Dec;94(1):e106. doi: 10.1002/cpns.106. PMID: 33151027; PMCID...detection, and control. Int J Pharm. 2018 Oct 25;550(1-2):251-268. doi: 10.1016/j.ijpharm.2018.08.043. Epub...addgene.org Addgene's Antibody Purification Protocol Addgene's Video Antibody Purification Protocol Addgene's Antibody...cells can perform human-like post-translational modifications that bacterial and most yeast cells cannot. ...production system may depend on what downstream applications you are planning, cost, and the amount of protein...
  22. Negative Can Be Positive: Open AAV Data with Addgene

    Type
    Blog Post
    Published
    Sept. 6, 2022, 1:15 p.m.
    ...across scientific disciplines. Scientific Data, 8(1), 1–11. https://doi.org/10.1038/s41597-021-00981-0 Wright...occurrence during vector purification and formulation. Molecular Therapy, 12(1), 171–178. https://doi.org...excellent at infecting our target neurons (Figure 1). However, this one set of experiments didn’t provide...yet none of that data was published.    Fig. 1: Testing of three different AAV serotypes (AAV1, 8...Stimulation. Frontiers in Human Neuroscience, 14(December), 1–12. https://doi.org/10.3389/fnhum.2020.578687 Additional...caudal NST. (A-C) Low-magnification images showing viral spread. (D-F)  High-magnification images immuno-stained... right AAV for your system or to successfully replicate published works. Of particular importance to these...
  23. Droplet Digital PCR for AAV Quantitation

    Type
    Blog Post
    Published
    Jan. 16, 2020, 2:18 p.m.
    ...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...take to achieve a clean NTC: Have a dedicated bench with a dedicated set of pipettes for ddPCR set-up. .... Each droplet contains the ingredients for amplification of the target DNA. This partitioning reduces...
  24. CRISPR Antimicrobials

    Type
    Blog Post
    Published
    May 3, 2016, 2:30 p.m.
    ..., 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...containing a phage origin of replication that can be packaged into replication-incompetent phage particles...essential processes: cell wall synthesis, DNA replication, or protein synthesis. Because they target such...
  25. Quick Guide to All Things Lentivirus

    Type
    Blog Post
    Published
    March 21, 2017, 2:30 p.m.
    ...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. "...
  26. SciComm with the Experts at Science in the News Part 1

    Type
    Blog Post
    Published
    March 16, 2017, 1:06 p.m.
    ...Science Communication Conversation in Science Communication The Purpose of Science Communication #1 Mistake...think about communicating science. Listen to the interview with Science in the News, Part 1 Podcast breakdown...supporters of science communication. To help you think about ways to effectively communicate your science, we...News at Harvard University. Effective science communication is required to promote public support for research... organization that works to promote science communication. Science in the News hosts a podcast, seminars...That’s right, #ActualLivingScientists, eager to communicate their science. In this first half of our two-...Mistake Scientists Make when Communicating with Non-Scientists How to Approach Different Audiences Listen...
  27. Technical Design of a Western Blot

    Type
    Blog Post
    Published
    Aug. 22, 2024, 1:15 p.m.
    ...Tris-tricine 2.5–40 kDa Tris-tricine 30 V, 1 hour or 100 V, 1–2 hours Good separation, quality, and stability...lot to cover, so let's dive in!      Figure 1: The technical decisions to make when designing a ...assay. The most common options are 4 °C overnight or 1–2 hours at room temperature (RT). Most people choose...overnight at 4 °C and their secondary antibody for 1–2 hrs at room temperature, which allows them to reduce...weight of the proteins you’re interested in. Table 1 lists the most common types of gels for SDS-PAGE running...gel chemistry and/or specialty gel options. Table 1: Types of gels  Gel Type Protein sizes Running... Tris-glycine 6–400 kDa Tris-glycine 100 V, 1–2 hours Easy and cheap to handcast Short shelf-life...
  28. Getting to Know Expansion Microscopy

    Type
    Blog Post
    Published
    June 20, 2023, 1:15 p.m.
    ...protocols. A typical ExM protocol (Fig. 1) follows this structure: Step 1: fix (and maybe label) your sample...microscopy. Nat Biotechnol 1–12. https://doi.org/10.1038/s41587-022-01546-1  Mikhaylova M, Cloin BMC, ...just adding water.)  Step 5: Image   Figure 1: The ExM process allows you to physically magnify ...16:71–74. https://doi.org/10.1038/s41592-018-0238-1  Klimas A, Gallagher BR, Wijesekara P, et al (2023...with an abundance of protocols and examples of applications from across disciplines now available. In this...experiment or evaluating ExM images in a new publication.         Why Expansion Microscopy?  Traditional...microscopes sounds great, right? But there is always a catch - some limitation of the technique that users should...
  29. Plasmids 101: Gateway Cloning

    Type
    Blog Post
    Published
    Jan. 12, 2017, 3:30 p.m.
    ...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...attP sites of the donor vector. This reaction is catalyzed by the BP Clonase enzyme mix and generates the...
  30. Viral Vectors 101: What is a Virus (and a Viral Vector)?

    Type
    Blog Post
    Published
    Aug. 18, 2023, 4:15 p.m.
    ...Virus Replication. Essential Human Virology, 49. https://doi.org/10.1016/B978-0-12-800947-5.00004-1 Taylor... 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...methods of replication. In fact, an entire classification scheme, known as the Baltimore replication classes...that in a bit! Viral genomes and replication When it comes to replication, viruses tend to march to the ...developed around how they replicate (Figure 2). Figure 2: Baltimore replication classes. Image credit: ...
  31. Viral Vectors 101: Virus Safety

    Type
    Blog Post
    Published
    June 22, 2023, 1:15 p.m.
    ...including yourself as the researcher.   Figure 1: Separation of retroviral packaging components onto distinct...these reasons, AAV is usually classified as a BSL-1 safety level. Adenovirus is similar to AAV in that...lab coats are either recommended or required in BSL-1 and required in BSL-2 labs. When working with lentivirus...required whenever there’s a splash or spray risk in BSL-1. In BSL-2 labs, eye protection is required any time...isopropyl alcohol, 0.5% peracetic acid, 10% bleach, or 1% iodine are useful. Some organizations or cities may...host genome, the virus is replication incompetent, meaning it can’t replicate and continue the infection... tools, thought was given on how to keep the replication of virus and its infectivity in check. Engineering...
  32. An Interview with Connie Cepko - Gene Therapy, Plasmid Tools and Insights to Success

    Type
    Blog Post
    Published
    Dec. 8, 2015, 3:30 p.m.
    ... 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... PMCID: PMC4096992. Find plasmids from this publication at Addgene. 2. Tang, Jonathan C.Y., et al. “...PubMed PMID: 26258682. Find plasmids from this publication at Addgene. Resources on the Addgene Blog Read...
  33. Sleeping Beauty Awakens for Genome Engineering

    Type
    Blog Post
    Published
    June 30, 2015, 2 p.m.
    ...comprised of 2 components: 1) an SB transposase, the enzyme required for catalysis of transposition; and 2...also important for social and regulatory reasons. 1.) The transposon consists of a mirrored set of inverted...likely to grow in the coming decades.  References 1. Kowarz E, et al. Optimized Sleeping Beauty transposons...T cells to target CD19. Immunol Rev. 2014 Jan;257(1):181-90. doi: 10.1111/imr.12137. PubMed. Find the ... Specifically, viruses are able to infect and replicate in host cells, but they are susceptible to cells... though not all, of these defenses. For some applications of genome engineering - such as certain forms...to integrate. Additionally, the TA sequence is duplicated near the gene of interest insertion site.   The...
  34. High Complexity Golden Gate Assembly with NEB’s DAD

    Type
    Blog Post
    Published
    Aug. 1, 2023, 1:15 p.m.
    ...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...assemblies are possible, the two sets of data together indicate that 35-pieces is a reasonable upper limit for...
  35. Fluorescent Tagging of Endogenous Genes with SapTrap

    Type
    Blog Post
    Published
    Oct. 12, 2017, 2:26 p.m.
    ... 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,...Toolkit for High-Throughput CRISPR/Cas9 Gene Modification in Caenorhabditis elegans.” Genetics. 202(4)...
  36. Plasmids 101: FLEx Vectors

    Type
    Blog Post
    Published
    April 28, 2016, 2:30 p.m.
    ...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. Schnßtgen F, Doerflinger N, CallÊja C, Wendling O...sites directs the Cre recombinase to invert, translocate, or excise a DNA fragment. The availability of... the function of various point mutations and truncations in the absence of the endogenous gene. Spatio-temporal...
  37. Twenty Years of Sharing: Expanding Accessibility

    Type
    Blog Post
    Published
    Nov. 21, 2024, 10:47 p.m.
    ...experiment.     Table 1: Most popular guides, protocols, and collections of 2023. Educational Resource Top...visitors in 218 countries. In Table 1, you can see our most popular educational resources for each type of resource...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... execute a step can provide needed clarity (Table 1). Our most popular video, however, is “What is a Plasmid...logistical barriers, allowing people to access a wide catalog of plasmids from all over the world. This idea,...
  38. Adeno-associated Viruses (AAVs) for Genome Editing

    Type
    Blog Post
    Published
    March 27, 2018, 1:32 p.m.
    ...infection, gene targeting vectors with relatively short (1 kb) homology arms underwent homologous recombination...sequences of interest to cells with efficiencies of 1-40% after G418 selection (Kohli et al 2004, Kim et...with polylinkers for the addition of gene-specific 1 kb homology arms flanking a FLOXed neoR gene. pAAV-SEPT-Acceptor...since it routinely generates knockin efficiencies of 1-40% with G418-selected clones. However, there are ...efficiency of gene editing is occasionally less than 1%, and virtually never exceeds 40%. While this is comparable...gene inactivation in human cancer.     References 1. Russell, David W., and Roll K. Hirata. "Human gene...gene at once. Therefore, applications that require simultaneous modification of all alleles of a gene,...
  39. PiggyBac-ing Through the Genome Editing Field

    Type
    Blog Post
    Published
    May 31, 2016, 3:30 p.m.
    ...Correct Path.,” J. stem cell Regen. Biol., vol. 1, no. 1, Jan. PubMed PMID: 26702451. PubMed Central PMCID...known upper limit [1]. The piggyBac™ technology can be used for numerous applications, including transgenesis... Figure 1: Mechanism of the piggyBac™  transposase/transposon gene modification system and the ...genetic manipulation in mammalian cells until 2005 [1]. Like other transposons, piggyBac™ has two components...The predicted frequency of ‘TTAA’ in the genome is 1 in every 256 base-pairs of DNA sequence, making it...technologies and strategies for their projects. References 1. L. E. Woodard and M. H. Wilson, “piggyBac-ing models...technology that may be used for a variety of research applications, including making transgenic cell lines and ...
  40. Antibodies 101: Choosing the Right Isotype

    Type
    Blog Post
    Published
    April 6, 2023, 3 p.m.
    ..., rather than a broadly  reactive secondary (Fig. 1). For example, an anti-mouse IgG2a secondary would...IgG2a>IgG2b>IgG1 (Manning 2012).      Figure 1: Broadly reactive versus subclass-specific antibodies...antibody binding and therefore the signal strength (Fig. 1). Monoclonal primaries If you do decide on a monoclonal...raised in a different species.      Table 1: Isotype considerations when choosing antibodies ...Elsevier. https://doi.org/10.1016/s0091-679x(08)60255-1  Manning, C. F., Bundros, A. M., & Trimmer, J. S. ...your experiment (all well validated for your application, of course!) When the stars are aligned and the...factors that affect isotype choice. Target and application should be considered The first question you may...
  41. Multiplex Genome Editing with CRISPR-Cpf1

    Type
    Blog Post
    Published
    May 9, 2017, 2:12 p.m.
    ...For these experiments, cells were infected with a 1:1 ratio of two AAVs,  one expressing Cpf1 and the other...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...leave them in the comments below.        References 1. Zetsche et al. "Multiplex Gene Editing by CRISPR–... a simple and effective method with multiple applications (in vitro, in vivo, transfection, viral transduction...Resources Find CRISPR Plasmids for Your Research Catch up on Your CRISPR Background with Our Guide Pages...
  42. Which Fluorescence Microscopy Techniques is Best for Me?

    Type
    Blog Post
    Published
    Oct. 10, 2017, 1:57 p.m.
    ... microscopy contrast technique in modern biology (1). When performed correctly, fluorescence microscopy...relatively thicker three dimensional sample (see Figure 1); similar to an MRI or CT scanner. This is accomplished... the resolution of a light microscope (see Figure 1). What microscopy technique should I use for my experiment...new sample I always start by asking two questions: 1) Is the sample dynamic or static? 2) Is the sample...modern day fluorescence microscopes (see Table 1). Thin dynamic samples Ex: monolayers of live cells with...excitation light can push imaging depths closer to 1 mm. Traditionally, 2-photon has been a very slow imaging...manufacturers have similar information References 1. Lichtman JW, Conchello JA. Fluorescence microscopy...
  43. Pathways Over Time Plasmids Engage Students in Functional Genomics Research

    Type
    Blog Post
    Published
    May 22, 2018, 1:38 p.m.
    ...research experiences to undergraduate students (1, 2), but educators face significant challenges in designing...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...about Clare at the Biology Dept. site.  References 1. American Association for the Advancement of Science... become very different due to a whole genome duplication and extensive rearrangements in the S. cerevisiae...overexpression vector. This plasmid contains origins of replication and selectable markers that allow students to...
  44. Tips for Titering Your Lentiviral Preps

    Type
    Blog Post
    Published
    March 15, 2016, 2:30 p.m.
    ...type of assay is a clonal cell line known to contain 1 integrated copy of the qPCR target gene. Developing... successful transduction experiment. References 1. Kutner, Robert H., Xian-Yang Zhang, and Jakob Reiser...Production, concentration and titration of pseudotyped HIV-1-based lentiviral vectors."Nature protocols 4.4 (2009... titration methods."BMC biotechnology 6.1 (2006): 1. PubMed PMID: 16836756. PubMed Central PMCID: PMC1534021...events." Genetic vaccines and therapy 2.1 (2004): 1. PubMed PMID: 15291957. PubMed Central PMCID: PMC514534...particle. Consequently, titers based off of p24 quantification tend to be overestimates since they can include...quantify the amount of PCR product that comes from amplification of the original plasmid which can over-inflate...
  45. Using AAV for Neuronal Tracing

    Type
    Blog Post
    Published
    Aug. 9, 2018, 1:04 p.m.
    ...but also others including pseudorabies virus type 1, vesicular stomatitis virus (VSV; Beier et al., 2011...Skeletal Muscle AAV1, AAV6, AAV7, AAV8, AAV9 Table 1: Common AAV Serotypes and their target tissues (adapted... serotypes capable of entering neurons (see table 1)(Choi et al., 2005; Taymans et al., 2007; Howard et...efficiency, tropism and axonal transport of AAV serotypes 1, 2, 5, 6, 8 and 9 in the mouse brain. PLoS One 8:e76310...Wolfe, J.H. (2014). Adeno-associated virus serotypes 1, 8 and 9 share conserved mechanisms for anterograde...,9 in rat neurons and glia in vitro. Virology 372(1), 24–34. PubMed PMID: 18035387. PubMed Central PMCID...transduction efficiency of recombinant AAV serotypes 1, 2, 5 and 8 in the rat nigrostriatal system. J Neurochem...
  46. Optimizing Donor DNA for Enhanced CRISPR Genome Editing

    Type
    Blog Post
    Published
    March 24, 2016, 2:30 p.m.
    ... Figure 1 below) was free to anneal to complementary ssDNA molecules in vitro. Figure 1: Cas9 binding...Corn Lab Members who worked on this publication:         References 1. Richardson, Christopher D., et al...allowed sequence replacement rates of approximately 1%. This is by no means a large number, but it was attained... reagent. This interplay falls into two broad categories and thus, causes two types of editing outcomes...altering its function). HDR is crucial for certain applications, for example, correcting the allele that causes... dissociation rates and discovered that the catalytically active form of the nuclease dissociates very...we measured identical dissociation rates for catalytically inactive dCas9 molecules. We followed these ...
  47. Deep Dive: qPCR

    Type
    Blog Post
    Published
    Sept. 29, 2022, 1:15 p.m.
    ...(a) (b)  (c)   Fig. 1: Melt curves showsing (a) a single peak, indicating one amplicon and no primer...PCR products in a rich web application, Bioinformatics, Volume 27, Issue 7, 1 April 2011, Pages 1019–1020...relatively easy to multiplex (Thellwell, 2000). See Table 1 for a comparison of features of several commonly used...in primer Yes Yes Agarose gel Table 1: Features of various qPCR chemistries. Adapted from...changes in ΔΔCT are represented by RQs between 0 and 1. Flipping your experimental and control values during...see this fold change as a positive difference (RQ>1), which may be easier to conceptualize. Just remember... in Molecular Biology, vol. 1160, DOI 10.1007/978-1-4939-0733-5_3, © Springer Science+Business Media New...
  48. Making CRISPR Plasmids Using Fragmid

    Type
    Blog Post
    Published
    Aug. 29, 2024, 1:15 p.m.
    ...building it! Table 1 has a list of Fragmid destination vectors currently available. Table 1: Fragmid destination...components on the Fragmid website.   Figure 1: (Top) Schematic overview and timeline of the Golden... CRISPR vector the Fragmid way!    Figure 1: Selecting your vector type on the Fragmid website...components available will depend on your answers in step 1, so you’ll only be able to select components that ...ampicillin resistance cassette and an origin of replication, which are not schematized. Sizes of fragments...five months. When they tested those clones (in duplicate), 93% had the correct banding pattern in the restriction...correct. Because they created the assemblies in duplicate, they were able to confirm that at least one plasmid...
  49. How-to: 5 Steps to a Great Panel Discussion

    Type
    Blog Post
    Published
    Oct. 22, 2014, 1:57 p.m.
    ...not let the panelists introduce themselves. I do a 1-2 minute introduction. If you chose good panelists...take 5 minutes to introduce themselves and, voila, 1/2 of your time is gone with no interesting discussion...introductions. The moderator asks questions, calling on 1-2 panelist for each question in a way that elicits... time you are at a talk and the speaker goes over 1 hour, watch what happens to the attention of the audience...postures shift, they are checking out. If you can, plant 1-2 good questions with trusted audience members. A ... about making sure the audience is interested, educated and talking as a result of the content. Here are...contribute. The moderator should identify the funny, provocative or interesting stories that will make for a fun...
  50. Common Injection Routes in Mice

    Type
    Blog Post
    Published
    Jan. 22, 2025, 9:42 p.m.
    ...mechanical restraint Location: back or hind legs Gauge: 25–27 Volume: < 2–3 ml (~1 ml per site) Skill required...! Table 1: Summary of common injection routes in mice. Injection Route Restraint Location Gauge Volume... advanced and finally, to expert.   Figure 1. Visual representation of common injection routes ...hind legs; between skin and muscle 25–27 < 2–3 mL (~1 mL per site) Beginner Intradermal Anesthesia Between...resources on the Addgene blog Mouse Modeling Part 1 Mouse Modeling Part 2 Five Popular Model Organisms.... It sounds complicated but has a pretty low learning curve! Restraint: scruffing Location: throat Gauge... Restraint: mechanical restraint or anesthesia Location: tail vein or retro-orbitally Gauge: 27–30 Volume...
Showing: 51 - 100 of 597 results