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We narrowed to 634 results for: des.2

Showing: 81 - 100 of 634 results
  1. No Llamas Required - Synthetic Nanobodies Against Membrane Proteins

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    ...-CoV-2 receptor-binding domain. BioRxiv.  https://doi.org/10.1101/2020.04.16.045419.  Wrapp D, De Vlieger...select for optimal sybody candidates. Figure 2: Outline of the process for selection of sybodies ...identify and isolate sybodies targeting the SARS-CoV-2 Receptor Binding Domain found on the membrane-bound...Generation Toolbox kit. Find the Seeger lab's SARS-CoV-2 sybodies! References Geertsma ER (2013) FX Cloning...Zimmermann et al., 2020). This selection platform was designed so that any standard lab can quickly select for...strongly to your target protein. The Seeger lab designed 3 different mRNA sybody libraries for use in the... randomized with a defined set of different trinucleotides (corresponding to different amino acids) in...
  2. When is a Monomer not a Monomer? The Top Three Ways Your Favorite Fluorescent Protein Oligomerizes in Cells

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    ... non-physiological, and difficult to ignore [1, 2]. 2. Fusion to an obligate dimer or oligomer Several...Biol, 2003. 163(2): p. 257-69. PubMed PMID: 14581454. PubMed Central PMCID: PMC2173526. 2. Zacharias, D....changes that the biosensor is designed to detect resulting in false positives [2, 4]. Solutions to the polymer...an A206K mutation [2]. Addgene has many of these constructs and they are designated mEGFP, mVenus, etc...analytical ultracentrifugation [2]. Some affinity assays used in the papers describing the FPs above including... nature are prone to dimerization (i.e. EGFP) [1, 2] or even form obligate tetramers (i.e. DsRed) [3]....form dimers in a cell. The Kd of EGFP is 0.11 mM [2]. Following the simple logic outlined above, you might...
  3. Scientists Map the SARS-CoV-2-Human Interaction Network

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    ...published an article on BioRxiv describing a comprehensive SARS-CoV-2 virus-human interaction network ...comprises all SARS-CoV-2 viral proteins except for Nsp3 and Nsp16, and includes an additional catalytically...all became acutely aware of the threat of SARS-CoV-2. Like many in the science community, we’ve been motivated...network in which we expressed 26 of the 29 SARS-CoV-2 viral proteins in human cells and used these viral “bait...identifying these potential human helpers of SARS-CoV-2 (especially the ones that are druggable) is a key ...just at the beginning of understanding how SARS-CoV-2 interacts with human proteins. For example, we used... joining in this worldwide fight against SARS-CoV-2. As we’ve all been affected in various ways by the...
  4. PRIDICT: Predicting Efficiencies of Prime Editing Guide RNAs

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    ...References Akhtar, W., De Jong, J., Pindyurin, A. V., Pagie, L., Meuleman, W., De Ridder, J., Berns, A....some of the best designs (e.g., top 5) and test them in their labs. Figure 2: Guidelines to predict... flanking sequences to their input string (Figure 2). This string can then be used as input for the prediction...Biotechnology. https://doi.org/10.1038/s41587-024-02268-2 Schep, R., Brinkman, E. K., Leemans, C., Vergara, ...this means we could design hundreds to thousands of different pegRNAs for each desired edit, it simply becomes...via GitHub (which includes prediction in batch mode). To predict the best pegRNA design for a specific edit...or offline via GitHub. The model provides users with different designs of pegRNAs, ranked by their PRIDICT...
  5. 22 Hot Plasmid Technologies from 2014

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    ...Currently available from the Kim lab are 2 presynaptic and 2 postsynaptic targeting mGRASP plasmids. Additionally...bacterial mutagenesis or gene targeting Victor de Lorenzo's lab has engineered a modular mini-Tn5 vector... cells were pulsed with 2µg/ml of Doxycycline for 2 hours, and imaged on the Keyence BZ-9000 fluorescence...work! Robinson et al., Dev Cell 2010 Feb 16;18(2):324-31. Cheeseman et al., J Cell Sci 2013 May 1...promotes the formation of an isopeptide bond between 2 peptide tags, SpyTag and KTag. The group demonstrated...on channelrhodopsins – Chronos & Chrimson Through de novo sequencing of 127 algal transcriptomes, as well... of three sets of cloning vectors (Level 0, 1, or 2) which can be utilized in three successive assembly...
  6. Tips for a 1st time AAV user (by a Rookie AAV user)

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    ...then packaged into AAV’s protein shell, or capsid; 2) the pHelper plasmid which expresses adenovirus genes...takes ~3 hours to complete: 1 hours hands-on time and 2 hours for the qPCR run and data analysis. Refer to... Special thanks for Dr. Dan Stone and Harshana de Silva Feelixge at Fred Hutchinson Cancer Center for...quantification of adeno-associated virus serotype 2-derived inverted terminal repeat sequences. Human ...therapy methods, 23 1, 18-28. PubMed PMID: 22428977. 2. Choi, V.W., Asokan, A., Haberman, R.A., & Samulski...plasmids to produce AAV: 1) the RepCap plasmid which provides the AAV replication (rep) and capsid (cap) genes...replication; and 3) the transfer plasmid which encodes a transgene of interest that’s packaged into the...
  7. Negative Can Be Positive: Open AAV Data with Addgene

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    ...clear and detailed methods and image descriptions, a minimum n = 2, and well labeled high- and low-magnification...indicated they wanted to see more negative data (Figure 2.) At the same time, when scientists who support open...is not only housed, but encouraged.    Fig. 2: Results from a survey conducted by Addgene in 2021...392–400. https://doi.org/10.1038/s41434-018-0028-5 de Backer, M. W. A., Brans, M. A. D., Luijendijk, M....gene therapy trials. Human Gene Therapy Methods, 26(2), 71–76. https://doi.org/10.1089/hgtb.2015.040 Initiative...of negative data.  Negative AAV data is highly desirable  In a survey we conducted to improve our Addgene...every researcher experiences and that it often provides incredibly valuable insight into one’s work. As...
  8. Lentiviral Vector Uses and Overview

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    ...create the 2nd-generation lentiviral system (Figure 2). The HIV genes that do remain are very important ...1996 Apr 12;272(5259):263-7. PubMed PMID: 8602510. 2. A third-generation lentivirus vector with a conditional...CH, Humeau LM, Rebello T. J Gene Med. 2013 Feb;15(2):78-82. PubMed PMID: 23322669. 6. Genetic treatment...to sickle cell disease. Hoban MD, Orkin SH, Bauer DE. Blood. 2016 Feb 18;127(7):839-48. PubMed PMID: 26758916... Banasik MB, McCray PB Jr. Gene Ther. 2010 Feb;17(2):150-7. PubMed PMID: 19847206. Additional Resources... but without sustained transgene expression. To design a viral vector system that could do both, Addgene...infect. Finally, the transfer plasmid encoded the desired transgene flanked by HIV-1 long terminal repeats...
  9. Lighting Up Cell Signaling with Photoswitchable Kinases

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    ...status of MEK1/2 was tracked at 5 minute intervals via Western blot. Phosphorylation of MEK1/2 peaks at just... phosphorylated MEK1/2 levels, suggesting PP1/PP2A is responsible for this MEK1/2 negative feedback. ...PubMed PMID: 28232577. Figures 2-4 were modified from this reference. 2. Regot, Sergi, Jacob J. Hughey...precisely control the timing of kinase activity. 2. Studying negative feedback loops of signaling pathways... studied the negative feedback on endogenous MEK1/2 phosphorylation by creating a short pulse of psRaf1...activity. They did this by exposing psRaf1 to a short 2 minute pulse of 500 nm light (turn on psRaf1) followed...Solution: In Zhou et al, the Lin lab present a generic design for creating photoswitchable kinases and use MEK1...
  10. Viral Vectors 101: Integrase-Deficient Lentiviral Vectors

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    ...or non-homologous end joining (see Figure 2).  Figure 2: Schematic representation of integration...Therapy, 17(2), 150–157. https://doi.org/10.1038/gt.2009.135. PubMed PMID: 19847206 Desfarges, S., & Ciuffi...due to insertional mutagenesis (Howe et al., 2008). 2. Transient expression of transgenes/shRNAs If you ...Brugman, M. H., Pike-Overzet, K., Chatters, S. J., de Ridder, D., Gilmour, K. C., Adams, S., Thornhill,...efficiently during infection. Journal of Virology, 70(2), 721–728. https://doi.org/10.1128/JVI.70.2.721-728.1996...been a staple in molecular biology for over three decades. Widely used across various research applications...and human papillomavirus (HPV), to name a few (Desfarges & Ciuffi, 2012). One family of viruses, retroviridae...
  11. Viral Vectors 101: Pseudotyping

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    ...safely. Recently, many SARS-CoV-2 researchers began pseudotyping the SARS-CoV-2 spike protein into a lower ...SARS-CoV-2 virus. Scientists have been using similar pseudotyping methods with other viruses in a BSL-2 lab... et a., 2018).   Figure 2: To pseudotype with the SARS-CoV-2 spike protein, scientists encode...production uses three plasmids: (1) The transfer plasmid, (2) the envelope plasmid, and (3) the packaging plasmid...example, production of vesicular stomatitis virus, HIV-2, and human foamy virus in cell lines expressing galactosyl...for Pseudotyping Lentiviral Particles with SARS-CoV-2 Spike Protein for Neutralization Assays. Viruses 12...Are Inactivated by Human Serum. Molecular Therapy 2:218–222 . https://doi.org/10.1006/mthe.2000.0116 Gutierrez-Guerrero...
  12. Antibodies 101: Normalization and Loading Controls for Western Blots

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    ...the resulting fraction is reported. Figure 2: Normalization with loading controls. Under each lane...control band is weaker in condition 1 than condition 2, the normalized values for the two conditions are ...opposite change in your loading control. Assumption #2: The loading control can be accurately quantified ...significantly lighter in “condition 1” than “condition 2.” By eye, the loading control appears about the same...) are smaller than the analogous green “condition 2” points by the exact same value. For the two solid...consider a different loading control. Assumption #2: The loading control can be accurately quantified ...factors we’ve covered in our previous blog posts (1, 2) on western blotting. If the abundance of your POI...
  13. Lambda Red: A Homologous Recombination-based Technique for Genetic Engineering

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    ...generate 2 possible products: 1) a partially dsDNA duplex with single-stranded 3’ overhangs or 2) if the... site (Figure 2, top).  These primers are typically ~70 nucleotides long (20 nucleotides that anneal to... genomes. 2) Designing ssDNA oligos that avoid MMR activation:  There are two ways to design oligos that...that has key MMR proteins knocked out or 2) specially design ssDNA oligos to avoid MMR: 1) E. coli with...recombineering system has three components (Figure 1): 1) Exo, 2) Beta, and 3) Gam. All three are required for recombineering...generic lambda red recombineering experiment (Figure 2). In the following sections, key steps that differ...confirmation of recombinant clones.    Figure 2: Overview of using Lambda Red recombineering system...
  14. Typing CRISPR Systems

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    ...   Class 1 versus class 2 There are two CRISPR classes: Class 1 and Class 2. Class 1 CRISPR systems use...systems to carry out various functions. Class 2 Class 2 CRISPR systems rely on a single protein Cas effector...explore Class 2 CRISPR in more depth, the Jennifer Doudna lab maintains an encyclopedia of Class 2 CRISPR systems...systems: a burst of class 2 and derived variants. Nature Reviews Microbiology, 18(2), 67–83. https://doi.org...remains largely underutilized compared to Class 2. Class 1 Despite their incredible abundance, Class 1 CRISPR...complex for antiviral defense) complexes, while Class 2 use single protein Cas effectors, like Cas9. The Cascade...components present in the Cascade complex. Figure 2: Schematic of a Cascade complex (blue subunits) with...
  15. Adenoviral Vector Production and Troubleshooting

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    ...repeated multiple times (2-4 rounds) at increasing scale over the course of 1-2 weeks. Each round of amplification...creating adenoviral vector constructs. It consists of 2 plasmids: a shuttle vector (in which the transgene...Addgene’s Adenoviral Guide webpage, and references 1, 2.*Pro-Tip*: once the correct recombinant pAdV plasmid...sequenced to confirm its integrity. Initial production (2-3 weeks) - Here you’ll produce the primary recombinant...media will turn yellow. Do NOT change the media (add 2-3 mL of fresh media once a week), and do NOT harvest...it will result in very low titer. Amplification (1-2 weeks) - The rAdV-S is used to infect more HEK293 ...in a 10-100-fold increase in virus. Purification (2 days) - Purification is required if rAdV is to be ...
  16. Giving gRNAs a Facelift - Synthetic and Beyond

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    ...same site, is 2’-fluoro (2’-F), which substitutes a fluorine for the hydroxyl group at the 2’ position. ...most common of these is 2’-O-methylation, where a methyl group is added to the 2’ hydroxyl group of the...gRNAs. Photocleavable guides are generated by introduction of a single photocleavable 2-nitrobenzyl linker...them together, for example phosphorothioates with 2’-O-methyl modifications, proved more stability than...to simply swap out several of the ribonucleotides for deoxynucleotides. A partially DNA gRNA is surprisingly...use in applications like siRNA and antisense oligonucleotides. Some of these synthetic modifications, specifically...Additional resources on the Addgene Blog  How to design your CRISPR gRNA CRISPR 101: Ribonucleoprotein ...
  17. Antibodies 101: Fab Fragments

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    ...fragments that retain antigen binding (Figure 2):  F(ab')2 - These fragments are produced by proteolytic...fragments are produced by mild reduction of F(ab')2 fragments, which reduces the hinge region disulfide...Variable (scFv). Size: ~25 kDa.   Figure 2: Comparison between a full IgG antibody and common...advantages, though with some caveats.  First off, F(ab’)2 fragments are bivalent, so may have higher avidity...or Fab fragments. Higher avidity means that F(ab’)2 fragments may have overall stronger interaction with...Clinical Prospects of Antibody Fragments. Antibodies 8(2):28. https://doi.org/10.3390/antib8020028    Wessel...multiplexed super-resolution microscopy. Cell Rep Methods 2(10):100301. https://doi.org/10.1016/j.crmeth.2022.100301...
  18. Viral Vectors 101: Virus Safety

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    ...cancer. These viruses need to be handled in a BSL-2 (or BSL-2+) lab and require additional safety measures.... BSL-1. In BSL-2 labs, eye protection is required any time you have to work with BSL-2 materials, such...respiratory diseases in humans, earning this virus a BSL-2 classification. Lentivirus (a type of retrovirus) ...recommended or required in BSL-1 and required in BSL-2 labs. When working with lentivirus, many organizations...sprayed into the air. For lentivirus and other BSL-2 materials, you’ll need to use aerosol-tight caps, ...percentage of the decontaminate to be used for BSL-2 waste, and of course, if you are working with a substance...that are built into how something functions, were designed for this purpose. One such control is dividing...
  19. Plasmids 101: Knockout/Knock-In Plasmids

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    ... recombinase (Figure 2). Figure 2: A knockout targeting vector designed to insert and later remove...process, we’ll walk through an experiment designed to knock out exon 2 of a given gene.   Figure 1:...   Design your targeting construct. For recombination to occur in a cell, a minimum of 2 kb of sequence...multiple ways. The desired recombination event will remove NeoR only and leave exon 2 floxed, as seen in...construct to your target cells. After recombination, exon 2 of the targeted gene will be removed from the chromosome...the GFP/NeoR cassette is inserted in place of exon 2. Thus, the targeted gene is disrupted (knocked out...often use the Cre/Lox system described earlier. In this case, you design your targeting vector such that...
  20. Great Results Start with Great Standard Curves

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    ... Figure 1 depicts a 2-fold dilution series. Each step of the series dilutes by 1:2 for a series that ranges...series ranging from 1:2 to 1:32. Each individual step of the series is consistent at 1:2. When preparing a.... An example of this is shown in Figure 2.   Figure 2: The concentration of a serially diluted... ranges from 1:2–1:32. The specific dilution series used will depend on the expected concentration of ...accuracy of the curve, avoid pipetting small volumes (< 2 µL) or volumes too large for a standard micropipette... the data points generated by replicate values provides useful information about the accuracy of the curve...If the unknown sample’s measurement is too low, redesign the standard curve dilution series with lower ...
Showing: 81 - 100 of 634 results