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We narrowed to 1,013 results for: CAL

Showing: 401 - 420 of 1013 results
  1. Plasmids 101: Protein tags

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    Blog Post
    ...purification (TAP) once referred specifically to a combo tag comprised of a calmodulin binding peptide (CBP), a...to) purification, detection, solubilization, localization, or protease protection. Thus far Plasmids 101...overexpress and purify proteins can face any number of technical challenges depending on their protein of interest...consider junk protein. Though there are a number of chemical and peptide-based proteosome inhibitors, glutathione... relatively small sequence of amino acids, is basically a molecular leash for your protein. If you’re ...want to combine a fluorophore with a tag that localizes your protein to the nucleus? Or you want multiple...
  2. Controlling for Off-target Effects with a New Genome-wide CRISPR Screen Design

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    Blog Post
    ...results (i.e. mistakenly calling a gene a hit when really it’s not). In practical terms, this means that... approach for identifying genes involved in a biological process. These screens provide an alternative...cutting than full-length guides (19-20bp)?  Small-scale studies (Tsai et al., Fu et al.) suggest 17-19 bp...non-targeting guides on screen analysis and hit calling. 5,644 non-targeting guides and 6,750 safe-targeting...ricin screen. When safe-targeting guides are used to call hits from the growth screen, p-values were less ...References 1. Morgens, David W., et al. "Genome-scale measurement of off-target activity using Cas9 toxicity...
  3. Viral Vectors 101: Preparing Pooled Libraries

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    Blog Post
    ... prep library. Addgene’s pooled libraries are typically DNA preps, but we do distribute several of our...larger lentiviral preps can be used for screening-scale transduction of cells, resulting in cell population...The size and composition of your library can drastically impact what conditions it needs to properly amplify...can transduce your cells.  While Addgene uses a physical titer (via ddPCR) to quality control our viral...include a 1.3 mL aliquot with mostlibrary requests specifically to allow scientists to perform functional titering... D., Sanjana, N. E., & Zhang, F. (2017). Genome-scale CRISPR-Cas9 knockout and transcriptional activation...Waxmonsky, N. C., Swanson, L. E., & Fan, M. (2016). Practical Considerations for Using Pooled Lentiviral CRISPR...
  4. Hot Plasmids Spring 2024

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    ...Emily Bentley Building on their CROPseq method for optical pooled CRISPR screening, Paul Blainey’s lab has...multiplexing approach to Cas9-based pooled CRISPR screens called CROPseq-multi (Walton et al. 2024). This platform...compatible with enrichment, single-cell sequencing, and optical pooled screens in human cells. Addgene offers vectors...one of the virus’s most abundant proteins and a critical component for viral genome packaging. Addgene ...Genetic modification of microglial immune cells is critical for central nervous system research; however, ...cells.      Figure 5: A) Representative confocal images showing GFP expression from ssAAV5s with...gene of interest, reducing the immunogenicity typically associated with viral vector-based therapies. ...
  5. Grad School Advice Part 1: Picking a Lab and a Project

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    Blog Post
    ...Harvard Medical School, and is currently a fellow in clinical genetics at the University of California, Los...Vincent and Niroshi Senaratne, from the Biological and Biomedical Sciences program at Harvard University...the Program in Genetics and Genomics at Harvard Medical School. He studies developmental gene regulation...
  6. Grad School Advice Part 2: Building Community

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    Blog Post
    ...Harvard Medical School, and is currently a fellow in clinical genetics at the University of California, Los...Niroshi Senaratne and Ben Vincent from the Biological and Biomedical Sciences program at Harvard University...the Program in Genetics and Genomics at Harvard Medical School. He studies developmental gene regulation...
  7. Tips for Getting a Faculty Position

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    Blog Post
    ...colleges, private universities, and medical schools. I will emphatically deny that I have a magic formula..." manual on applying for faculty positions in biomedical science. My motivation was to share my experiences...told all of the nuances of the research in as technical of language as possible. Seriously. My suggested... trying to say X." She would then look at me quizzically and ask why I didn't just say that? Bottom line...especially helpful. I set out to make something practical and accessible. If there's something you come ...the Janelia Research Campus of the Howard Hughes Medical Institute. His interests include the quality control...
  8. The Fluorescent Vegetables in Aptamer Soup

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    Blog Post
    ...able to bind to a small molecule derivative of GFP called 3,5-difluoro-4-hydroxybenzylidene imidazolinone...intracellular locations using Cas9 and track the localization of the complex. Broccoli, the other green fluorescent...Broccoli, and useful for quantitative studies. Specifically, Corn was developed to quantify RNA transcription...high-affinity complex for RNA labeling and tracking." ACS chemical biology 9.10 (2014): 2412-2420. PubMed PMID: 25101481...and directed evolution." Journal of the American Chemical Society 136.46 (2014): 16299-16308. PubMed PMID...di-GMP and cyclic AMP-GMP." Journal of the American Chemical Society 135.13 (2013): 4906-4909. PubMed PMID:...a photostable RNA–fluorophore complex." Nature chemical biology 13.11 (2017): 1187. PubMed PMID: 28945233...
  9. Plasmids 101: Expressing shRNAs for RNA Interference

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    Blog Post
    ...structures that are processed by a ribonuclease called Dicer. In a great simplification of the process...pri-miRNA, which is then processed by a complex called Drosha to pre-miRNA. miRNA plasmids are engineered...backbone Choosing the promoter Mature siRNAs typically range from 19–22 nucleotides and are 100% complementary...’t just use the mature sequence in a plasmid and call it a day. You need to include both sides of the ...for quick in vitro experiments. shRNA plasmids typically use RNA polymerase III promoters, which transcribe... versatile gene-silencing machine. Journal of Biological Chemistry, 284(27), 17897–17901. https://doi.... DICER: structure, function, and regulation. Biophysical Reviews, 13(6), 1081–1090. https://doi.org/10.1007...
  10. Antibodies 101: Normalization and Loading Controls for Western Blots

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    Blog Post
    ... why you might want to be careful relying on so called “housekeeping proteins.” Fully quantifying a western... later steps in this chain (blue) to infer or calculate things about earlier ones. In practice, multiple...popular choices for loading controls. These are often called “housekeeping proteins” and are detected with an... will almost certainly be overloaded. One paper called this problem “the most common error associated ...Data is presented as mean ± SEM. Adapted from Analytical Biochemistry, vol 440, Gilda, J. E., & Gomes,...loading control to β-actin for Western blots. Analytical Biochemistry, 440(2), 186–188. https://doi.org...Antibodies 101: The Basics of Western Blotting Technical Design of a Western Blot Troubleshooting and Optimizing...
  11. Antibodies 101: Beyond Surface Labeling

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    Blog Post
    ...populations; for example, CD8+ T (“T killer”) cells. Typically, you would label the CD8 co-receptor protein on...of interest via FACS using negative selection is called dump gating. Let’s say we want to sort out all ...cell membrane but inside the cell. Due to their chemical nature, antibodies cannot penetrate the cell membrane...intracellular labeling with antibodies requires chemically pre-treating the cells to allow for entry of ...esterified dyes that can enter cells freely are typically used. Inside the cell, the ester group is cleaved...intracellular labeling protocol is necessary, requiring chemical treatment of the cells after surface labeling....Associate in the lab of Arlene Sharpe at Harvard Medical School. His projects include investigating negative...
  12. How to Negotiate a Successful Lab Start Up Budget

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    Blog Post
    ...where you can start to identify which items aren’t critical to your research success. If you can get away ...resources to keep, and which ones to abandon. It’s critical to make these decisions in the following order... budget can help you compare the monetary and empirical value that helps you determine whether or not ...know how to decide which components are the most critical to your research, negotiations can be much easier...negotiating finances, instead of solely discussing numerical values, try to keep conversations focused on research...saving the institute time and energy that would typically be wasted going through some of the questions ...is your goal, then understanding your needs is critical to a successful negotiation and collaboration....
  13. Optogenetics + CRISPR, Using Light to Control Genome Editing

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    Blog Post
    ...temporal and spatial control. Optogenetics uses genetically encoded tools, such as microbial opsins, to control...light-inducible heterodimerizing cryptochrome 2 (CRY2) and calcium and integrin-binding protein 1 (CIB1) proteins....this approach. This study generated the first optically active saCas9 protein. Stop light! Photoactive...different approach. These researchers used a genetically encoded photocaging technique to insert a light-removable...light-removable protecting group, specifically a nitrobenzyl photocaged lysine (PCK), on the Cas9 protein...Hemphill et al. presented data showing that this genetically encoded, photocaged Cas9 system could silence...editing and transcription. Label genomic loci Photochemical Control Hemphill et al., 2015   Nitrobenzyl-caged...
  14. CRISPR/Cas9 FAQs Answered!

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    ...it's usually more efficient than plasmid donor. Typical design is to have 50–80 bp of homology arms on ...changes (>100 bp insertions or deletions), we typically use plasmid donor, with two homology arms on each...transfection in cells like HEK, we use around 400 ng of a typical size (~5 kb) donor plasmid with Cas9/sgRNAs vector...plasmids. For ssDNA oligo design, the Zhang lab typically uses around 100–150 bp total homology. The mutation... giving 50–75 bp homology arms. The Zhang lab typically use PAGE purified long oligos. For large changes...100 bp insertions or deletions), the Zhang lab typically uses a plasmid donor, with two homology arms on...like HEK, the Zhang lab uses around 400 ng of a typical size (~5 kb) donor plasmid with Cas9/sgRNAs vector...
  15. What's New in CRISPR - December 2019

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    Blog Post
    ...deaminase (TadA) to a catalytically impaired Streptococcus pyogenes Cas9. They called this editor Target-...-to-inosine (A-to-I) RNA editor called REPAIR by fusing catalytically inactivated RNA-targeting Cas13 ...plasmids available at Addgene. We will still periodically focus on specific CRISPR plasmid tools more ...editor still retains A-to-I editing. This system is called RNA Editing for Specific C-to-U Exchange, or RESCUE...
  16. Bringing Sustainable Practices to the Lab: Innovations

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    Blog Post
    ...you’ve saved. Repurposing regulated medical waste Regulated medical waste (RMV), which we collect in those...scores products by their environmental impact on a scale of 1-10: the lower the score, the lower the environmental...companies to obtain these labels! Reusing plastic Historically, scientists washed and reused materials such...flow cytometers. These fluidic machines handle biological samples and are cleaned between each use. You...those red biohazard bags, typically is destined for a landfill. However, Triumvirate Environmental developed...
  17. CRISPR Protocol for Genomic Deletions in Mammalian Cell Lines [Video]

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    Blog Post
    ...Regulatory DNA function is typically inferred based on correlative biochemical characteristics and ectopic...Canver of Boston Children’s Hospital and Harvard Medical School. Addgene is proud to present a video reprint...for deletion screening by conventional PCR. Biallelically disrupted cells can be easily identified. Even...investigator at Boston Children’s Hospital and Harvard Medical School. His lab studies the molecular genetics ...Matthew Canver is an MD/PhD student at Harvard Medical School in the laboratories of Stuart Orkin and ...
  18. Future of Research Conference - Remarkable Opening Session

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    Blog Post
    ...Kristin Krukenberg and Jessica Polka from Harvard Medical School and a long list of supporters from all of...peer review and grant awards systems need to be radically overhauled.  Finally, the science publishing system...excellence to begin effecting change.  Panelists call for action Each of the speakers in the panel had...Director of the Office of Postdoctoral Affairs at UNC, called her presentation “Disequilibrium, Disillusion and...Associate Professor of Systems Biology at Harvard Medical School, titled her presentation “How to Train Your...and take action. More Reading: “Rescuing US biomedical research from its systemic flaws” by Bruce Alberts...
  19. CRISPR 101: Off-Target Effects

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    Blog Post
    ...expression by various mechanisms. The RNA guide is typically 20 nts and the genomic locus must often be proximal...promiscuous. In other words, they can sometimes localize to unintended sites with sequence similarity to... the on-target site. When a CRISPR-Cas system localizes to unintended sites and performs its programmed...product with CRISPR to (hopefully) be used in human clinical trials. An off-target rate of 5% is far too high...Cas-OFFinder, CCTop, and many more. While such software typically only considers DNA sequence and doesn’t take into...deadCas activator/repressor experiments where only localization of the Cas occurs. 2 gRNA approach Off-targets...effectiveness as a control. Since off-targets typically confound an experiment due to their location (...
  20. Viral Vectors 101: Optogenetic Tools

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    Blog Post
    ...Deisseroth, K. (2005). Millisecond-timescale, genetically targeted optical control of neural activity. Nature...Ganguli, S., & Deisseroth, K. (2019). Cortical layer-specific critical dynamics triggering perception. Science... activated tools, can control everything from electrical activity to gene expression, and even CRISPR ...through multiple intra-cellular signaling cascades. Optical methods for controlling GPCR activation have been...
Showing: 401 - 420 of 1013 results