Skip to main content
Addgene
Showing: 401 - 420 of 862 results
  1. Hot Plasmids December 2018 - C. elegans RNAi, TurboID, Detecting Viral Outbreaks, and Protein Binding Specificity Tools

    Type
    Blog Post
    Published
    Dec. 6, 2018, 1:34 p.m.
    ...complexes with LacZ𝜔 and forms an active LacZ tetramer.  This tetramer cleaves chlorophenol red-b-D-galactopyranoside...particular strain of norovirus, it can be tailored for the detection of other norovirus strains and even.... elegans. These dsRNAs target specific mRNA transcripts for degradation. Despite how easy these experiments...often completely ineffective or results in low penetrant phenotypes that are hard to study. To overcome...target gene between two inverted T7 promoters. Transcription from each promoter progresses past the specific...promiscuous labeling enzyme and a small-molecule substrate to map the spatiotemporal distribution and interaction...virus costs time and money, and viruses at low concentrations often escape detection. The Alexander Green...
  2. The Many Reasons for Irreproducible Research- and a Vaccine to Eradicate It

    Type
    Blog Post
    Published
    Jan. 30, 2020, 2:15 p.m.
    ... if not archived. Remove bias with preregistration Preregistration is the process of creating a time-stamped...and funders in the Transparency and Openness Promotion Guidelines; preregistration to increase clarity... sampling and inference-making. Even perfect transparent and rigorous studies will give false signals ...repository before conducting the experiment (note: registrations can be embargoed while the research is ongoing... tested with a specific statistical test.  Preregistration makes clear the distinction between hypothesis...author submits the research plan (similar to a preregistration, but usually with a fully fleshed out introduction...for Open Science in order to reward increased transparency and reduced bias in scientific research. These...
  3. Plasmids 101: Methylation and Restriction Enzymes

    Type
    Blog Post
    Published
    June 30, 2016, 2:30 p.m.
    ...dam–/dcm– strain of E. coli such as JM110 and re-purifying it. These specialized E. coli strains have been...DNA. The other component of these systems, methyltransferases, methylate DNA at particular sequences to...restriction modification systems containing methyltransferases that add methyl groups to specific DNA sequences...effectively cleave DNA. Common lab E. coli K12 strains such as DH5alpha contain 3 methylases that recognize...plasmids with no methylation (there are no methyltransferases in the PCR reaction). The template plasmid...other hand, should be derived from a dam+ E. coli strain and will therefore have methylated adenines in ...site blocked by methylation), the figure below illustrates how sequence visualization software (we used ...
  4. How to Keep a Lab Notebook for Bioinformatic Analyses

    Type
    Blog Post
    Published
    June 2, 2016, 2:30 p.m.
    ...-lab experiments using a “traditional” lab notebook; however, keeping track of computation work comes ...to keep track of why you are doing what you are doing. Another common challenge is to keep track of what...was run. This technique leaves a trail that further helps you keep track of your exact changes. Alternatively...was contributed by guest blogger Kate Palozola Traditional lab notebooks just won't cut it for bioinformatics...began, I realized that I needed a system to keep track of the files that I was continuously generating....comment in C++ and Java Command line history: Tracking command line history by recording all commands...Learn about Software You Can Use to Save Time and Track Your Experiments Try out the CRISPR Software Matchmaker...
  5. Plasmids 101: Blue-white Screening

    Type
    Blog Post
    Published
    June 4, 2015, 1:03 p.m.
    ... do just that! (To read about other screening strategies, check out our screening overview blog post.)...β-galactosidase enzyme can break down a dye-linked substrate called x-gal (5-bromo-4-chloro-3-indolyl-β-D-galacto-pyranoside...α-peptide) to a lacZΔM15-mutant bacterial cell in trans complements the mutation allowing for a functional...produces pigment from x-gal (included in the transformation plate medium), turning the bacterial colony...IPTG is also included in the medium to ensure transcription of the lac operon.   Tips for blue-white screening...screening Use a good control: Transform the backbone plasmid without insert. All colonies on this plate...restriction digest. Make sure you use a proper E. coli strain (i.e. contains the lacZΔM15 mutation): XL1-Blue...
  6. Career Coaching for Scientists: Why and Where Do I Find One?

    Type
    Blog Post
    Published
    Jan. 29, 2015, 1:25 p.m.
    ...they have certifications? How can they demonstrate their track record? Look for a coach that specializes...help with transitioning out of academia (because so many scientists are making this transition). Another...have experience and knowledge to help scientists transition out of the academic sphere into a different meaningful...not always as effective in mentoring for this transition. Second, a coach will help you set goals and ...scientific backgrounds. For a stated purpose of transitioning a scientist from academia to industry, you might...in coaching for communication skills. Industry transition is also an area of specialty for Michelle Capes...it can be helpful having a coach that can offer extra support for issues of diversity in science.  A great...
  7. Generating Mouse Models Using CRISPR/Cas9

    Type
    Blog Post
    Published
    July 12, 2016, 2:30 p.m.
    ...3.4% of founders establishing germline transmission of the transgene, this technique is still in need of ...and chimeric adults mated to produce completely transgenic offspring. Although powerful, this technology...the run, it got “dirty”, with multiple sequence traces overlapping each other! When the count was done...technology, CRISPR, that is simple in concept, straightforward to use, and robust in performance. In its natural...the Cas9 endonuclease that creates the DNA double-strand break (DSB) at the target site, and a donor oligonucleotide...conventional methods. First, one can work with almost any strains of mice, as compared with conventional gene targeting...targeting, which is limited to a few strains, including 129 and C57BL/6, for which we have germline competent...
  8. Plasmids 101: Restriction Cloning

    Type
    Blog Post
    Published
    Feb. 18, 2016, 3:42 p.m.
    ...uncut plasmid. 4. Transformation Transform your ligation reaction into your bacterial strain of choice. Follow...perform, at minimum, two transformations after a ligation: 1. Control Transformation containing the ligation...purification method, it is important to determine the concentration of recovered DNA as this will be useful for ...is difficult to calculate this based on DNA concentration alone. One method is to conduct 2 ligations ... how many colonies you should expect in the transformation due to background re-circularization and contamination...competent cells. For most standard cloning, you can transform 1-2μl of your ligation reaction into competent...ligation mixture with backbone alone; 2. Transformation containing ligation mixture with insert and backbone...
  9. CRISPR in the Clinic

    Type
    Blog Post
    Published
    Nov. 2, 2023, 1:15 p.m.
    ...cocktail therapy for urinary tract infections. The Cas3 enzymes target several strains of E. coli and lethally... fibrosis (Schwank et al). They were able to demonstrate functional correction of the gene in clonally...  Figure 1: Types of delivery and editing strategies for CRISPR therapies. Systemic therapies involve... CAR-T immunotherapy for cancer treatment by traditional gene therapy pipelines (viral), and researchers...CRISPR targets — Sickle Cell Disease (SCD) and Transfusion-dependent beta thalassemia (TBT), both of which...affect hemoglobin. Most of the targeted treatment strategies for these disorders have involved turning on ...clinical trial for SCD in 2022 as well. Hereditary transthyretin amyloidosis (hATTR) hATTR is caused by a variety...
  10. A Guide to Designing a Scientific Poster: Content, Layout, and More

    Type
    Blog Post
    Published
    Oct. 22, 2019, 12:20 p.m.
    ... Large central box. Another commonly used and effective style is one employing a large central box, often...can be accomplished with an exciting title and attractive figures. Next, the poster should be legible from...different one for the body of those sections. This strategy helps your sections stand out, and makes the entire...at least the majority of the visual data. This central box is then flanked by two equally-sized columns...prominently, making it the star of your presentation. Portrait. This style displays a poster vertically rather...the introduction, methods, and figures flank the central region, and a scannable barcode is included that...presenting. The latter is catchy, but beware. A distracting background or clashing colors can take away from...
  11. The AAVantages of AAV in CRISPR Screens

    Type
    Blog Post
    Published
    Feb. 4, 2025, 2:15 p.m.
    ...vivo starts with transducing cells with the CRISPR library in vitro before transplanting them into mice....expression of lentiviral vectors make them an attractive option. However, safety requirements and expression...expression limitations may be too constraining for some experiments, particularly in vivo ones. In those...lentiviral vectors being packaged using VSV-G. In contrast, AAV can be packaged in a variety of capsids. ...portions of the AAV genome can integrate at double-stranded break points caused by CRISPR-Cas9 editing. The...target cells or tissues. AAV also shows improved transduction efficiency over lentivirus in many mouse tissues... Even more creative options involve generating strains of mice that stably express Cas effectors in specific...
  12. Anatomy of a Plasmid Page at Addgene

    Type
    Blog Post
    Published
    Feb. 4, 2016, 3:30 p.m.
    ... end up on the N or C terminus of the transcribed and translated insert. If it is an empty vector with...the name of the strain.  Most Addgene plasmids are maintained in the E. coli lab strain DH5a, but others...colleagues. Top of the plasmid page The ‘breadcrumb’ trail at the top of any plasmid page gives the hierarchy... see in the example above that the bread crumbs trail starts in the browse page, continues through the...This section describes how to grow the bacterial strain in which the plasmid is shipped. Copy number (if...others may require strains such as ccdB survival (for Gateway plasmids).  We also like to store plasmids ...plasmids that need extra stability, such as some of our viral vectors, in NEB Stable cells. Resource information...
  13. What's New in CRISPR - March 2020

    Type
    Blog Post
    Published
    March 10, 2020, 1:15 p.m.
    ... expressed both dCas9 and the ctrA sgRNA and saw that the levels of ctrA mRNA decreased after 20 minutes...The system consists of dCas9, the mammalian transcriptional repressor Mxi1, and an optogenetic tool that...Serial dilutions of CRISPRi in Caulobacter cells for ctrA gene expression using various dCas9. Image adapted...test their CRISPRi system, the Laub lab repressed ctrA, a gene encoding an essential cell cycle regulator...which controls expression of dCas9). The lab demonstrated the system can also be used to downregulate ...CRISPRi plasmids A multiplexed gRNA piggyBac transposon system for human pluripotent stem cells Lindy...and gRNAs whose expression varies depending on transgene design and delivery. They generated hPSC lines...
  14. Typing CRISPR Systems

    Type
    Blog Post
    Published
    March 18, 2025, 1:15 p.m.
    ...successor to traditional RNA interference, as it can target and degrade select RNA transcripts, or be engineered...categories, arriving at a consensus was not as straightforward as it seems. There is not a single gene that.... Type I systems are also employed as CRISPR transposases, by leaving out Cas3. Type I is further subdivided...promoter, allowing for easy multiplexing. The double-stranded breaks caused by Cas12 create short 3’ overhangs...paradoxically called V-K, is a CRISPR-associated transposase (CAST) that can insert large fragments of DNA...use a Cas14 enzyme, and uniquely target single-stranded DNA non-specifically. Type VI Type VI is defined...proteins. A type VII is already on the horizon (Altae-Tran et al., 2023)! References and Resources References...
  15. Plasmids 101: Gateway Cloning

    Type
    Blog Post
    Published
    Jan. 12, 2017, 3:30 p.m.
    ...sequencing or restriction digest! Then, you can transform or transfect the cells that you want to use for your...project, scientists are no longer limited to traditional restriction enzyme cloning. Instead, you can ... reactions are performed, the next step is to transform competent E. coli cells and select the positive...expression clone. You will also need to use a E. coli strain sensitive to CcdB (e.g. DH5α, TOP10, Mach1). The... inhibits the growth of CcdB sensitive E. coli strains, most colonies should contain the desired, recombined...of the KRAS coding sequence. If you choose this strategy, it’s important to include the proper protein ...reading frame considerations, etc). This video demonstrates how to use the Snapgene program to design Gateway...
  16. Plasmids 101: Positive and Negative Selection for Plasmid Cloning

    Type
    Blog Post
    Published
    Aug. 22, 2019, 12:43 p.m.
    ...selection strategy, here are a few to consider. Antibiotic selection Selection is straightforward in cases...re-ligated back on themselves. Therefore, your cloning strategy needs to identify cells containing the plasmid...includes an antibiotic resistance marker. After transformation, plate the cells on medium containing the corresponding...selection will select for cells that have been transformed with the plasmid backbone (with or without your...ve designed your experiment using an auxotrophic strain of bacteria (one that doesn’t synthesize an essential... the critical amino acid). Many common E. coli strains used for cloning are auxotrophic for specific amino...Toxin-antitoxin systems One negative selection strategy uses the toxin CcdB. Gateway cloning takes advantage...
  17. Genetically-encoded Sparse Cell Labeling - A SPARC of Innovation

    Type
    Blog Post
    Published
    May 21, 2020, 1:15 p.m.
    ...expression of a transgene (Lin et al., 2018). However, this system requires precise titration of the AAV. ...visualize individual/non-overlapping cells. While transgenic animals are commonly used to specifically manipulate...are affected. Previous tools to overcome this restraint include an AAV-based sparse labeling system where...tools in Drosophila (Fig. 1):  GAL4-UAS, a transcription factor binding site. GAL4 expressed in the fly...site to cleave and inactivate any read-through transcripts of the effector gene. Effector genes, any gene...cassette remains following recombination. This strategy results in sparse labeling of the cell population...across cell types and organisms by replacing the transcription factor binding site and effector in the construct...
  18. Choosing Your Perfect Empty Backbone

    Type
    Blog Post
    Published
    Aug. 19, 2014, 3:39 p.m.
    ...). If you can get away with generating transiently transfected cells, you will not need a mammalian selection...design. You can create a new strain with a disrupted gene by transforming wild-type yeast with an integrating...whistles to your construct. If you are planning to track your protein in the cell or purify it – and you ...mammalian selection cassette to screen for positive transfected cells. The addition of an in-frame fluorescent...plasmid shuttle vectors. You may prefer the more traditional approach of an autonomously replicating vector...a wild-type version of YGOI to rescue a mutated strain or a mutated version of YGOI to test the different...applications used to study gene function. From making transgenic animals, gene targeting and genome modifications...
  19. Fluorescent Biosensors for Measuring Autophagic Flux

    Type
    Blog Post
    Published
    Jan. 22, 2019, 2:41 p.m.
    ...to the lysosome, and degradation of autophagic substrates inside the lysosome. Historically, methods for...autophagy, the untargeted Rosella remains in the neutral pH cytoplasm where it emits red and green fluorescence...mitochondria-targeting sequence, Rosella can be used to track the targeted autophagy of mitochondria, or mitophagy...Rosella can also be fused to a protein of interest to track the autophagy of that protein. Find the cytosol-targeted...proteases is key to its pH-dependent fluorescence. In neutral environments, dimeric Keima is excited at 440 nm...mRFP-GFP-LC3 Tandem Fluorescent Protein, but following translation, this fusion protein is cleaved to generate one...140.3 (2010): 313-326. PubMed PMID: 20144757. PubMedCentral PMCID: PMC2852113. Noda, Takeshi, and Daniel...
  20. 3 Tips to Improve HDR Efficiency for CRISPR Editing in Human Cells

    Type
    Blog Post
    Published
    Sept. 5, 2017, 1:58 p.m.
    ...com­plex is very efficient at introducing double stranded breaks (DSBs) into genomic DNA in many cell types...homologous DNA repair template, such as a sin­gle-stranded oligodeoxynucleotide (ssODN), which contains the...repaired by NHEJ. While other groups have focused on strategies to improve overall HDR rates, we have shown recently...developed a framework that, by combining these two strategies allows you to specifically incorporate homo- ...the cells. However, our excitement turned into frustration when we sequenced our cells and found how inefficiently...indels. Following this observation, we tested a strategy that was discussed in the field at the time but...to change the PAM site, however we have also demonstrated the efficiency of guide RNA blocking mutations...
Showing: 401 - 420 of 862 results