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  1. Hot Plasmids: FRET-Based Biosensors

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    Blog Post
    ...shy away from ratiometric imaging, he recommends they give it a shot. “Beginners sometimes think it’s complicated...imaging of transition metal ions, such as zinc, copper, and iron. “These are essential metal ions, but they ...neurons and T lymphocytes. Nat Methods. 2014 Jan 5. doi: 10.1038/nmeth.2773. (PubMed) Friedrich et al....which are available at Addgene, can be used for ratiometric in vivo imaging. Griesbeck explains, while these...possible for added sensitivity. As reported in Nature Methods, the FRET changes of these Twitch sensor variants...both neuroscience and immunology. Don’t be shy: Ratiometric imaging for beginners Griesbeck says his calcium...important and when? That is not known.” Transition Metals Maarten Merkx of Technische Universiteit Eindhoven...
  2. Sequencing Options for CRISPR Genotyping

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    ...older assays. Biased sequencing methods There are two primary methods of off-target detection: biased ...off-target effects of sgRNAs using computational methods. They identify possible off-target sites across...that they can later sequence for mutations. One method a researcher can use to test predicted off-target...disastrous health effects in the clinic. NGS-based methods provide the most complete information profile regarding...editing events. Two of the most common cell-based methods are genome-wide, unbiased identification of double-strand...all cell types Must be verified with cell-based method IDLV 1% Cell-based Programmable, can detect DSBs...in live cells Not as senstive as other unbiased methods, high background BLESS Not reported Cell-based...
  3. Quick Guide to Near-Infrared Fluorescent Proteins

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    ...eukaryotic cells as an intermediate of heme metabolism (Shemetov et al, 2017). Modern state-of-the-art NIR...iGECI calcium indicator (Shemetov et al., 2021). In addition to FRET, intensiometric calcium indicators NIR-GECOs... in NIR. Usually, mercury lamps are suboptimal, metal halide lamps are better, and xenon lamps are the...daria_gift_shch.     References and resources References Shemetov, A.A., Oliinyk, O.S. & Verkhusha, V.V. How to ...near-infrared fluorescent calcium ion indicator. Nat Methods 16, 171-174 (2019). Matlashov, M.E. et al. A set...scales. Nat Commun 11, 239 (2020). Oliinyk, O.S., Shemetov, A.A., Pletnev, S., Shcherbakova, D.M. & Verkhusha... antigen-dependent fluorescent nanobodies. Nat Methods submitted (2021). Tchekanda, E., Sivanesan, D. ...
  4. Hassle-free 96-well Format Epitope Tagging Using Cas9 Ribonucleoprotein

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    ...Nucleofection method for delivery of csRNP reagents into cells. Optimization of delivery methods (electroporation...-IN” design tool with the csRNP method. We anticipate that our method will open up immense possibilities...pull-down assays include immunoprecipitation mass spectrometry (IP/MS) and chromatin immunoprecipitation (ChIP... protein complexes are then analysed by mass spectrometry to identify the interacting proteins. Similarly...of the target protein. Both IP/MS and ChIP-seq methods provide a wealth of information about how protein...antibody (Jarvik and Telmer 1998). Indeed, this method can be used at high throughput because numerous...Bressan et al. 2017; Liang et al. 2017). Current methods of epitope tagging, however, suffer from many pitfalls...
  5. CRISPR 101: Ribonucleoprotein (RNP) Delivery

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    ...site for inserting a custom gRNA.  While this methodology has proven to be incredibly valuable to scientists...complications that must be considered when using this method:     Cells must be amenable to transfection or... to using RNPs for CRISPR experiments. The RNP method can often be used in cells that are difficult to...CRISPR plasmids) are not expressed. Because this method does not require the delivery of foreign DNA, and...CRISPR experiments using RNPs is the variety of methods that can be used to deliver a Cas9-gRNA RNP. This...systems that may not be amenable to plasmid based methods. One of the most common techniques for delivery...demonstrated the use of cationic lipid-mediated methods to deliver Cas9-gRNA RNPs to hair cells in the ...
  6. When Fidelity Matters: A frank discussion about ligase fidelity

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    ...sensitive, high-throughput method to accelerate characterization of nucleic acid metabolic enzymes." Nucleic acids... nicks with no gaps. For example, DNA assembly methods, such as Gibson Assembly® and NEBuilder® HiFi DNA... use fluorophore- quencher pairs or qPCR-based methods to greatly increase the sensitivity of detection...Biolabs® (NEB) researchers recently published a method for the high-throughput profiling of ligase fidelity...high-sensitivity multiplexed format (21, 27). This methodology has been used to rapidly screen buffer conditions...DNA Ligase and their effect on fidelity. In this method, substrate pools were prepared consisting of one...capillary electrophoresis (CE) (see below). This method allowed screening of all possible base combinations...
  7. AAV Titers: Where Do They Come From And What Do They Mean?

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    ... hybridization method (DNA dot blotting) had been used to titrate AAV, but this method is not widely used...2012). PCR-based methods are robust, easy, fast, and convenient. However, these methods are not necessarily...vectors and improved alternative methods." Human Gene Therapy, Part B: Methods 23.1 (2011): 1-7. PubMed PMID...of a viral vector solution, and generally these methods measure different characteristics of the solution...viral genomes (by qPCR or other DNA quantification methods - see below), since each viral particle typically...viral vector preparations. Addgene has used this method to generally validate our viral vector preparation... typically calculated by two popular PCR-based methods: Quantitative PCR (qPCR) Digital droplet PCR...
  8. Technical Design of a Western Blot

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    ...Journal of Neuroscience Methods, 172(2), 250–254. https://doi.org/10.1016/j.jneumeth.2008.05.00...make when designing the experiment. What detection method? What membrane? What should you block with? It...time to two days.  Indirect or direct detection method Indirect detection is the most common way to run...source, making it easy to switch from one readout method to another or change primary antibodies as needed...proteins, instead of the more common chemiluminescent methods for detection (though the enzymes used for chemiluminescence...denaturing blot.  There are a number of lysing methods and buffers to choose from. If you are starting... tissue, you’ll likely want to use a mechanical method before your enzyme lysis. For cell cultures, enzyme...
  9. Antibodies 101: Designing Your First Flow Panel

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    ...you can detect it through the APC-Cy7 parameter in the cytometer's software. It also means we should exclude...Introduction to Gating in Flow Cytometry Antibodies 101: Flow Cytometry Antibodies 101: Flow Compensation...When analyzing your cells using flow cytometry, you are typically measuring the presence or absence of... to give you the appropriate readout. A common method of labeling proteins is to fuse them with a fluorescent...reporters, and/or dye stains used in your flow cytometry experiment are known as your "panel". In this ...strength of the emitted photons detected by the cytometer. Brighter fluorophores have a stronger signal....from: https://emea.bd.com/panel-design/en/flow-cytometry-fluochrome-brightness-spillover Excitation...
  10. Antibodies 101: Introduction to Antibodies

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    ...study protein-protein interactions. Flow cytometry Flow cytometry is used to detect proteins on the surface...expression: The nuts and bolts. Methods 116:51–62 . https://doi.org/10.1016/j.ymeth.2017.01.009 Crivianu-Gaita...immune system production and many more engineered methods. Each type of antibody and production strategy ...recognizes the primary antibody and provides the method of detection. You’ll also want to use the appropriate...Enzyme-linked Immunosorbent Assay). Immunoprecipitation Sometimes, instead of just detecting the presence of protein...the mixture. Antibodies can do this, too! In this method, antibodies bound to microscopic beads grab the...The fluorescence signal is detected by the flow cytometer and functions as a proxy for protein expression...
  11. Plasmid Tools for Microbiome Studies

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    ...habitat (Ronda et al., 2019). They called their method Metagenomic Alteration of Gut microbiome by In situ Conjugation...Carlotta, et al. "Metagenomic engineering of the mammalian gut microbiome in situ." Nature methods 16.2 (2019... microbes. Let’s take a look at a few of these methods below. Engineering gut microbes in situ While...Harris Wang lab at Columbia University developed a method for genetically altering gut microbiome members... and diagnostic labs, deep sequencing and qPCR methods are too costly and time intensive to process a ...microbiome, James Collins’s lab developed a paper-based method that can be used to detect microbes and biomarkers...biomarkers on paper. At the heart of their method is the RNA toehold switch, a RNA hairpin that can be designed...
  12. Tips for Titering Your Lentiviral Preps

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    ...drawbacks of different methods (for comprehensive protocols for all of the methods discussed here refer ... in a matter of hours. A major drawback of this method, however, is that a p24 ELISA measures all p24 ... direct p24 measurement. Like a p24 ELISA, this method is relatively quick, providing results in less ... on the vector backbone. When using qPCR based methods for viral titration consider using a reverse transcriptase... Functional titer is considered a more accurate method to quantify virus as it only measures infectious...infectious viral particles. One of the si mplest methods of measuring functional titer uses FACS to count the...transduction with serial dilutions of a viral prep. This method is particularly useful when vectors carrying fluorescent...
  13. Deep Dive: Fixing and Permeabilizing for Immunofluorescence

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    ...acetone, methanol, or ethanol, work by dehydrating and precipitating cellular components. This method of fixation...introduction to immunofluorescence (IF) - a common method for visualizing molecules of interest within a ...tissue. In that introduction, we broke down the method into six general steps and outlined the considerations...saturated being 37%). Formalin solutions often contain methanol as well, in order to slow the polymerization of...recover good antibody binding by tweaking those parameters, but in some cases your antibody may just not...experiment.   Figure 1: Choice of fixation method impacts antibody binding. Formaldehyde cross-links...hidden within the folded protein (green region). Methanol dehydrates the protein, which can disrupt protein...
  14. Antibodies 101: Immunoprecipitation

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    ...then eluted. This method is appropriate for most situations.  A slightly different method is desirable if...typically carried out in one of two ways. Both methods utilize the same basic strategy: immobilize the...target protein is eluted.     In the first method, an antibody against a target protein is immobilized...if the target is present in low amounts. In this method, the free antibody is incubated with the protein...antibody-protein complexes, and as in the first method, unbound proteins are washed away and the target...protein. One of the most common immobilization methods utilizes bacterial cell wall proteins, Protein ..., the target protein can be eluted. The elution method will vary depending on the specific target protein...
  15. Plasmids 101: Broad Host Range Plasmids

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    ...Legionella pneumophila, Methylophilus methyltrophus, Methylococcus methanolicus, Methylosinus trichosporium, Myxococcus...Klebsiella aerogenes, K. pneumoniae, Methylophilus methylotrophus, Moraxella spp., Mycobacterium aurum...Klebsiella spp., Legionella pneumophila, Methylophilus methylotrophus, Myxococcus virescens, M. xanthus, Proteus...plasmids may have high copy numbers and reduced metabolic load (Meyer 2009). Figure 1: Idealized ...eutrophus, Azotobacter vinelandii, Brevibacterium methylicum, Caulobacter crescentus, Desulfovibrio vulgaris...plasmid vectors for gene expression in bacteria. Methods in Molecular Biology (Clifton, N.J.), 765, 327–...
  16. K. phaffii: Rising to the Occasion

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    ...cells and peroxisomes are where methanol metabolism occurs in methylotrophic organisms. K. phaffii is an ...obligate aerobe. It’s also a methylotropic yeast, meaning it can utilize methanol as its sole source of carbon...media change into methanol and peroxisomal autophagy can be induced by removing methanol from the media....protein animal feed. Due to increasing prices of methanol and advancements in other biomass production techniques...Preferred carbon source Glucose Glucose Glucose, methanol, glycerol Heterothallic mating Efficient...more similarity to the ancient yeast strains and metazoan cells.   Applications for K. phaffii There’s a... its powerful promoter of a gene important for methanol usage. This gene promoter, AOX1, was co-opted ...
  17. Deep Mutational Scanning with One Pot Saturation Mutagenesis

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    ...Several methods can be used to create mutational scanning libraries. While each of these methods works ...saturation mutagenesis. Error-prone PCR: This method amplifies the wild-type template with a “sloppy...5) the addition of MnCl2. Disadvantages of this method include favoring of certain types of mutations,...assembly. While this is a comprehensive mutagenesis method, a drawback to using Gibson assembly is that the...PFunkel: Of prior existing comprehensive mutagenesis methods, PFunkel offers the best combination of library...the phage-derived uracil labeled template, this method requires further DNA shuffling to combine pairs...tested in a functional screen of your liking. This method is similar to site-directed mutagenesis (SDM) PCR...
  18. Hot Plasmids: Summer 2024

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    ... resolution than using more complex protective methods or detergents like CHAPSO, while requiring a lower...particle orientations, this could be overcome with methods such as chemical crosslinking or tilted-stage imaging... stringent for eVLPs than other viral delivery methods, allowing all the PE components to be delivered...recent publication, the Liu lab showed that this method of delivery could be used to partially correct ...editor consisting of dCas9 fused to a DNA methyltransferase — that can drive lasting transcriptional silencing...Histone tail for Autoinhibition Release of Methyltransferase (CHARM), with several advantages over the ...  Rather than overexpressing an exogenous methyltransferase for epigenetic silencing, which can be toxic...
  19. What's New in CRISPR - March 2020

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    ...acetylation or demethylation. Casilio DNA Methylation Editing (Casilio-ME) is a methylation editing tool...for linking methylcytosine oxidation to DNA repair, which increases activation of methylation-silenced genes...human pluripotent stem cells CRISPR-based DNA demethylation Optogenetic repressors of gene expression ...Using several rapid and cost-effective screening methods, David Liu’s lab identified and validated CBEs ...organism for studying the bacterial cell cycle, asymmetric cell division, and cellular differentiation, ...Find the plasmids Enhanced CRISPR-based DNA demethylation Figure 2: The components of Casilio-ME1...Albert Cheng’s lab that enhances RNA-guided methylcytosine editing by TET1 by co-delivering TET1 and protein...
  20. IBEX Knowledge-Base: A Data Resource for Multiplex Tissue Imaging

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    ...multiplexed: you can image over 65 different parameters using this method (see Movie S8 from Radtke et al., 2020...IBEX is a highly multiplexed tissue imaging method that uses iterative staining and chemical bleaching...many conventional microscopes, amplified staining methods, and oligonucleotide-based staining. Of course,..., dye inactivation details, tissue preservation method, and detergents that they used in their experiments...Screenshot showing reagent entries with associated metadata adapted from the Affinity Reagent Working Group...Human Biomolecular Atlas Program (HuBMAP) antibody metadata standards. And the dataset is rich. Experimental... host organism, isotype, clone details, vendor, method, tissue preservation, target tissue, detergent,...
Showing: 181 - 200 of 843 results