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Showing: 301 - 320 of 951 results
  1. A New Optogenetic Tool Based on AraC Controls Gene Expression with Blue Light

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    Blog Post
    ...article.) Modifying AraC to create BLADE The team modified AraC to create BLADE by replacing its dimerization...images created by the team (Fig. 2). These images are based on the concept of bacteriographs created about...bacteriograph of Michelangelo's "The Creation of Adam." This bacteriograph was created using 160 individual images...dimerize and activates transcription. The team created two constructs, among others: pBLADE-mCherry:...about a decade ago. To create these images, the scientists used a strain transformed with pBLADE expressing...instead of mCherry under the PBAD promoter. They created a bacterial lawn on an agar plate, put a mask over... that Di Ventura’s lab and Khammash's lab have created and shared with Addgene. You can find all the plasmids...
  2. Cancer and the Immune System: Deciphering the Relationship

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    Blog Post
    ...Cancer cells find a way to grow haywire, access and create more vasculature to feed themselves, use the blood...the tumor microenvironment - a vital atmosphere created by the cancer cells to shield themselves from attack...cells of epithelial origin. Suppressing function, creating tolerance, and evading recognition are a few methods...cells into regulatory cells to suppress function. Creating Tolerance T-regs in the tumor microenvironment...HIF-1), which promotes the production of VEGF to increase angiogenesis around the tumor. This in turn regulates...signals released from the microenvironment help create tolerance beyond direct proximity to the tumor;...cells (DCs) and macrophages (M1 and M2) that help create welcoming environments for tumor cells spreading...
  3. 3 Tips to Improve HDR Efficiency for CRISPR Editing in Human Cells

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    Blog Post
    ...mutations increased the accuracy of editing by up to 10-fold per allele. This is a 100-fold increase in editing...incorporate homo- or heterozygous mutations. 1. Increasing HDR accuracy with CRISPR/Cas-blocking mutations...find the 0.2-0.5% correctly edited alleles, when screening reasonable amounts of single cell clones. Furthermore...tedious business of iPSC clone picking, a 100-fold decrease is the difference between picking 100 versus 10,000... together with the intended sequence change and screen a few hundred clones to find the right one Step... few hundred. From these two steps, you’ll be screening a total of a few hundred clones - Still better...efficiency of mutation incorporation falls with increasing distance from the cut site. If the distance is...
  4. Plasmids 101: Common Lab E. coli Strains

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    Blog Post
    ...recombination, increases plasmid stability recBCD Exonuclease V activity abolished Increased plasmid stability...that make major improvements such as those that increase plasmid yield and/or DNA quality. Table 1 below...sensitive. dnaJ Mutation in a chaperonin gene Increases the stability of certain expressed proteins ...methylate DNA lac Lac operon mutations Blue/white screening of clones   lacIq lac repressor overproduced...derivative. General cloning and storage, blue/white screening, leucine auxotroph. F- endA1 recA1 galE15 galK16...cloning and storage of common plasmids, blue/white screening. F- endA1 glnV44 thi-1 recA1 relA1 gyrA96 deoR...General cloning and plasmid maintenance, blue/white screening, partly restriction-deficient; good strain for...
  5. Lentiviral Vector Uses and Overview

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    Blog Post
    ...encoding Gag and Pol, increasing the number of recombination events necessary to create a replication-competent...Enable Genome-Scale, Knockout Screening Read about Genome-Wide Screening Using CRISPR/Cas9 Additional...shows how the lentiviral genome was condensed to create the 2nd-generation lentiviral system (Figure 2)...safer than the original system, the possibility of creating a replication-competent virus via recombination...possibility and enhance biosafety, Dull et al. created the 3rd generation system (Figure 3), which differs...Lentiviral vectors in the lab Lentiviral vectors are incredibly popular in the lab - the Trono lab’s lentiviral...both for targeted modification and genome-wide screening.   Lentiviral vectors in the clinic Since lentiviral...
  6. CRISPR 101: Cas9 Nickase Design and Homology Directed Repair

    Type
    Blog Post
    ...nuclease domains, researchers created the CRISPR nickase. Nickases create a single-strand rather than a...generated by the nickases; D10A creates 5’ overhangs and H840A creates 3’ overhangs in a PAM-out design...Conversely, the H840A mutation in the HNH domain creates a non-target strand-cleaving nickase. Instead of...strands bluntly with WT Cas9 and one gRNA, you can create a staggered cut using a Cas9 nickase and two gRNAs...other? The gRNAs must target different strands to create a DSB, but this can be accomplished with either...an individual gRNA with WT Cas9, repair levels decrease rapidly 10 bp from the cut site. So if you can... you can’t obtain high HDR efficiency. Nickases create a staggered cut - could this system mediate repair...
  7. Antibodies 101: Reading a Flow Plot

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    Blog Post
    ...Marker B. Created with biorender.com.   The goal of flow cytometry is to use increasingly more stringent...populations that are B+ and one population that is B-. Created with biorender.com.   If it’s hard to conceptualize...imagining (or drawing) a quadrant over the dot plot. Created with biorender.com.   Of course, this is quite...al., 2017 to identify mDCs and pDCs. Used under Creative Commons license.    In the third plot, anti-CD14...visualize the different populations. Used under Creative Commons license.    Pro tip! Subtypes of immune...the percentage of cells in each gate. Used under Creative Commons license.    Contour plots  FACS data...data from Jhunjhunwala et al., 2015. Used under Creative Commons license.  Histograms  For analysis...
  8. CRISPR Activation: A Practical Guide

    Type
    Blog Post
    ...in therapeutics, as it can increase gene expression at certain loci to create changes in phenotypes. For... storm. While Cas9 has been most widely used to create specific edits in DNA, there has also been significant...inducible upon environmental triggers. This is done by creating a split dCas9 protein that can reassemble when...the best uses for Cas9 activators is in genetic screening. gRNAs targeting every gene in the human genome...interactions. Additionally, large scale CRISPR-based screens can be used to gain insight into protein structure...focused advancing scientific discovery through the creation of innovative technologies. To date his group ...of cancer therapeutic targets using CRISPR–Cas9 screens. Nature 568:511–516 . https://doi.org/10.1038/s41586...
  9. Fluorescent Biosensors for Measuring Autophagic Flux

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    Blog Post
    ...autophagosomes with lysosomes leads to an increase in yellow puncta but a decrease in red puncta. Find the mRFP-...RFP ratio: a decrease in GFP fluorescence relative to RFP fluorescence suggests an increase in autophagic...flux, while an increase in GFP fluorescence relative to RFP fluorescence suggests a decrease in autophagic...yeast or the lysosome in mammalian cells. This decrease in pH quenches SEP but not DsRed, leading to emission...Therefore, the formation of autophagosomes leads to an increase of yellow puncta (GFF positive/RFP positive), ...fusion of an autophagosome with a lysosome. An increase in autophagy leads to more yellow and red puncta...
  10. Antibodies 101: Single Chain Fragment Variables (scFvs)

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    Blog Post
    ... rounds of screening. Created with Biorender.com.   Some phage display libraries screen antibody genes...serine with dispersed hydrophilic residues for increased solubility (Monnier et al., 2013). The linker ...expression systems. scFvs are also small enough to be screened for with in vitro display methods such as phage...applications where longer retention times often increase therapeutic efficacy (Ahmed et al., 2012). How...and VH sequences. Phage display also allows for screening scFv generated from the B cell antibody genes ...the ways antibodies are. scFvs are even used to screen for new antibodies. To do this, antibody variable...variable domain sequences are expressed as scFvs and screened with in vitro assays to select for strong binders...
  11. Site Directed Mutagenesis by PCR

    Type
    Blog Post
    ... are isolated from the resulting colonies, and screened for the desired modification. Finally, the positive...final circular plasmid product pictured here. B) Screening of recovered plasmids for the mutation of interest...multimerization (purple) which is evident by an increase in the size of the lower band (portion of the ...mutation). Similar results can be obtained with PCR screening using the primers specified by the arrowheads ... vastly facilitates the subsequent process of screening for succesfully mutated clones. Forward and reverse...Template A high purity plasmid prep significantly increases the success rate of site directed mutagenesis....secondary structures of the DNA template, and may also decrease the annealing temp of the primers. Because you...
  12. Fluorescent CRISPR Reporters: SRIRACCHA and GEmCherry2

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    Blog Post
    ...14 and 21 to create GEmCherry2. The Denham lab made several other small changes creating 2 other versions...Cas9 activity assays. Recently scientists have created CRISPR fluorescent reporter assays to quantify ...CRISPR/Cas-stimulated HDR activity) The Madison lab created SRIRACCHA in 2017 to enrich and identify desired...H2B-GFP. This visual read out allows for easy screening of different gRNAs by simply changing the gRNA...plasmid that contains Cas9. The Madison lab also created an inducible SRIRACCHA system (iSRIRACCHA) where... H2B-GFP expressing cells exhibited a 2-4 fold increase in the number of endogenous indel edits when compared... sites and activity (Knudsen et al., 2018).  To create GEmCherry2, the Denham lab first incorporated an...
  13. Uncertainty about Labor Law Brings More Uncertainty to Postdoc Wages

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    Blog Post
    ... the injunction. While much of this decrease is due to an increase in the number of universities’ whose...postdocs who were expecting a salary increase have had that increase cancelled. Rounding out the remainder...payment for working more than 40 hours per week increasing from $23,660 to $47,476 per year. This post discusses... of postdocs who weren’t going to get a salary increase prior to the injunction still won’t after the ...issues such as childcare using money from their increased salaries. In addition, salary uncertainty may ... costs of living would get much better salary increases that those in less densely populated areas. This...Gary's Previous Article: Changing Labor Laws Bring Increased Postdoc Wages Read about the Advocating for Science...
  14. Plasmids 101: Golden Gate Cloning

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    Blog Post
    ... of interest. Although efficiency may decrease with an increased number of fragments, or the ligation ... cleave outside of their recognition sequence, creating four base flanking overhangs. Since these overhangs... fragments, these problems can be overcome by screening a higher number of potential clones. Golden Gate...the ordered assembly of multiple DNA fragments to create TAL effector nucleases. These plasmids were designed...This cloning strategy not only makes it easy to create a single gRNA-expressing plasmid, but it can also...fragment: PCR-based amplification can be used to create silent point mutations at internal recognition ...Whether you are using the Golden Gate method to create CRISPR/Cas9 constructs, assemble standard plasmids...
  15. Educational Planarian Tools for Teaching Developmental Biology Techniques

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    Blog Post
    ...challenging for amateur scientists. Planarians, wormy creatures commonly found in freshwater ponds, provide a ...promoters to allow for bidirectional transcription to create dsRNA. Students can produce DNA templates via PCR... PCR off of the same plasmid and use these to create riboprobes for in situ hybridization experiments.... as how to perform worm amputations. They also created an online companion resource called “cutting class...within an embryo or tissue. Once the riboprobes are created, the WISH protocol involves preparation of the ...as a result, these cells turn blue. Students can create synthetic riboprobes off of linearized DNA templates...from their organism of interest, use the RNA to create a complementary DNA (cDNA), and then use PCR and...
  16. 3D Printing Meets CRISPR Cas9

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    Blog Post
    ...protein in your hand? At 3D Molecular Designs, we create physical models of proteins using 3D printing technology... real”.  We sometimes forget that the models we create are around 30 million times larger than the real...were soon developed that allowed researchers to create stunning, interactive images of their proteins....physical models of protein structure? We have been creating physical models of proteins for researchers for...educators and students use molecular models?   We created the Center for BioMolecular Modeling (CBM) in 1999... 1999 with the expressed purpose of creating physical models of proteins and other molecular structures...researchers to learn about their research while creating physical models of proteins that are being investigated...
  17. Microbes: Look, Listen, and Tell

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    Blog Post
    ...in vivo: acoustic reporter genes’ on our blog. Creative approaches to presenting the microbial world ...bacteria in the lab, I was excited to learn about creative approaches to visualize bacteria in an educational...educational setting. The Symposium on ‘Creative Approaches to Presenting the Microbial World’ showcased complex... comics (Dr. Sanja Saftic) to educational gifs created by the Amoeba Sisters. Here’s one example of how...lactose-around-we-can-make-some-enzymes-for   The take home message was that being creative and telling a story makes scientific topics both... fascinating to see the living art designed by creative minds with a (I assume) very steady hand. By connecting...connecting art and science, a fascinating interface is created that produces loads of inspiration for the current...
  18. Uncovering Ancestral Bias in CRISPR Research

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    Blog Post
    ...genome-wide screens, introducing bias into all work based on these and any other CRISPR screens using the..., race. Many researchers do large-scale CRISPR screens in cancer cell lines, looking to uncover genetic...targets and related biomarkers . Data from such screens are often uploaded to the Cancer Dependency Map...Boehm labs pulled data from more than 1000 CRISPR screens in DepMap to see if they could identify the ancestry... American, Africa, or South Asian) used in the screens based on the cells’ germline genetic variations...about 90% of the cell lines used in DepMap CRISPR screens are of either European or East Asian ancestry, ...actually reference?  The CRISPR guides used in the screens they analyzed were designed to have a perfect match...
  19. New Acoustic Reporter Genes: Ultrasound Imaging of Gene Expression

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    Blog Post
    ...vesicles with nonlinear contrast. Increasing expression and decreasing genetic footprint We took a cue ...heterologously by bacteria inside the body. So we screened gas vesicles gene clusters from a diverse set ...expression heterogeneity required single cell screening to isolate a clonal cell line capable of producing... expression to appreciable levels. We wanted to create second-generation mARGs with higher expression,...reduced the number of copies of gvpA needed to increase expression. We were able to express Anabaena ...expression leads to greater amount of gas vesicles and increased ultrasound contrast. In all the cell lines we ...their tracking with ultrasound imaging (Fig. 2d). Creating a cell line can be a time-intensive endeavor. ...
  20. Bioinformatics at Addgene

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    Blog Post
    ... we grew. As the number of deposited plasmids increased, the accompanying sequencing data collection and...bioinformatics workflow management system As novices to creating a robust data pipeline that would be reliable ...community of Nextflow supporters existed who had created a shared resource of pipelines for genomic data... with others without any complicated setup. We created, tested, and debugged each of our pipeline steps...running the pipeline locally and in the cloud. Creating a bioinformatics workflow in Nextflow Establishing...scripting language that can be executed on Linux, we created our first process by simply copying and pasting...was working as expected, we moved forward with creating the next process and linking the output from the...
Showing: 301 - 320 of 951 results