Skip to main content
Addgene
Showing: 421 - 450 of 1024 results
  1. Hot Plasmids: Summer 2024

    Type
    Blog Post
    ...epigenome editing. Cell, 184(9), 2503–2519.e17. doi: https://doi.org/10.1016/j.cell.2021.03.025.    Recombinant...tissue is identifying the cells you are studying. Antibodies can help reveal cellular identities by targeting...Trimmer’s lab (Figure 5) as well as antibodies for identifying other cell types in the nervous system!..., particle orientation distribution and Fourier-shell correlation curve (D), and the reconstructed 3D ...particles (eVLPs) offers an option to transduce cells directly with ribonucleoprotein cargo. eVLPs contain... will only be transiently present in transduced cells, limiting off-target editing. Cargo size limits ...site-specific integration of large genes in mammalian cells via continuously evolved recombinases and prime ...
  2. Overcoming the Challenges of Lentiviral Production

    Type
    Blog Post
    ...transfected into a packaging cell line, usually a derivative of 293T. Packaging cells are incubated and after...fine-tuning selection and expression in your target cell line, researchers often find themselves faced with...impact the transfection efficiency of the packaging cell line and thereby affect the titer of the virus. ...layer flask will require some initial optimization; cell number, media volume, and plasmid concentrations...larger vessel to the 10 cm2 dish and adjusting the cell number, plasmid concentration, and experimental ... consideration when titering a lentivirus is the cell line that is used for titering. Typically researchers...researchers will choose a relatively permissive cell line for titering in order to obtain the best titer possible...
  3. BeHeard Award 2018: Diseases of Glycosylation, Arginine Mutagenesis, & Neural Development

    Type
    Blog Post
    ... stem cells. The lab will use plasmids from Addgene to construct NFIX expression vectors as well as reporters...the physiological and pathological roles of human cell glycans. Accordingly, she joined efforts with the...aspect of immunology, participating in events such as cell development, recognition and migration, the immune... is not surprising. However, the molecular and cellular mechanisms behind the immune defects in CDG patients...plasmids to immortalize CDG patient-derived immune cell lines and use these lines to study how immune processes...and other pathological conditions. References: Monticelli, M., Ferro, T., Jaeken, J., dos Reis Ferreira...McMurray is an Associate Professor in the Department of Cell and Developmental Biology at the University of Colorado...
  4. Split-BioID: An Improved Method for Studying Protein-Protein Interactions

    Type
    Blog Post
    ... expressed in cells via plasmids or by the creation of stable cell lines and these cells are then grown... complex. Not performed in a native cell context. For AP-MS, cells are lysed before the bait protein is...and interacting proteins in mammalian cells. The Journal of cell biology. PubMed PMID: 22412018. PubMed... it allows for the validation of a binary PPI as well as the identification of additional interacting ...against PPIs that aren't stable outside the native cell context. The Split-BioID method Enter Split-BioID...protein interactions. However, FRET generally only tells you if two proteins interact and cannot be used ...tagging of proteins in both BioID or Split-BioID, cells are lysed, protein extracted, and labeled protein...
  5. Recombinase-based State Machines Enable Order-dependent Logic in vivo

    Type
    Blog Post
    ... require minimal cellular perturbation. Also, this method requires live, intact cells; the sequencing ...Synthetic recombinase-based state machines in living cells” (1), into a more straight-forward, concise explanation...mutations, and environmental conditions drive certain cellular behaviors, but little is known about the order... may be used to better understand and engineer cellular processes that are influenced by temporally ordered... one final state, then the state of the RSM will tell you precisely what inputs were added to the system... our paper (1), we allowed individual bacterial cells to form colonies on a plate and then we performed..., but more population-wide (as opposed to single-cell) approach is to interrogate state with qPCR. The...
  6. Drew Endy Introduces the Biobrick Public Agreement Plasmid Collection

    Type
    Blog Post
    ...metabolite in a cell. The only way to do that at scale right now is to grow up a bunch of cells, sacrifice ...capable of storing data and computing inside living cells. He's also a co-founder of the BioBricks Foundation...transistor-like digital genetic switches that enable cellular computing. These logic gates built from transcriptors... Collection along with a BIOFAB kit comprised of well-characterized bacterial transcription and translation...as an operating system for engineering an entire cell. Typically when people use plasmids, they are trying... you could imagine engineering the entirety of a cell. That's a big long-term technical challenge. We ...That's central to everything that goes on inside a cell. Until we get a handle on precise, forward engineering...
  7. Plasmids 101: Positive and Negative Selection for Plasmid Cloning

    Type
    Blog Post
    ... and zap the mixture of DNA into cells. Unfortunately, not every cell successfully takes up plasmid DNA...selection: Cells that have gained a specific gene survive In positive selection, only cells that contain...cassette, you would plate the cells on kanamycin-containing agar. Only cells carrying plasmids that contain...Therefore, your cloning strategy needs to identify cells containing the plasmid construct you’re seeking....resistance marker. After transformation, plate the cells on medium containing the corresponding antibiotic...these cases, antibiotic selection will select for cells that have been transformed with the plasmid backbone...plasmids to complement auxotrophy. Negative selection: Cells that have lost a specific gene survive Unlike positive...
  8. Understanding GPCR Signaling Using TRUPATH

    Type
    Blog Post
    ... to environmental conditions, cells must be able to detect extracellular stimuli. One way they do so is...bound to the intracellular surface of the GPCR. Binding of a ligand to the extracellular surface of the...play many roles in signaling processes including smell, taste, sight, inflammation, and neurotransmission...complex converts a signal received by a GPCR on the cell’s surface into action that can result in the initiation...number of signaling cascades, inducing different cellular responses. One of the biggest advantages of such...protein transducers. To use the TRUPATH system, cells are transfected with plasmids expressing the GPCR... and the appropriate Gγ-GFP2 and Gβ constructs. Cells are then treated with the luminescent enzyme substrate...
  9. AAVs in Retinal Gene Therapy

    Type
    Blog Post
    ...expression in non-dividing cells because they remain in episomal form in the cell’s nucleus. But since nothing...hope are many more clinical successes for gene (and cell) therapies. One may wonder why the first AAV-based... providing long-term gene expression in retinal cells - AAV - were becoming available. At the same time... lentivirus (LV) are known to transduce retinal cells, AAV quickly became the vector of choice for ocular...long term expression in dividing and non-dividing cells due to its (random) integration into the genome,...genome, and its large DNA packaging capacity is well suited for larger transgenes. Unfortunately it has limited...limited tropism in the retina, primarily infecting cells of the retinal pigmented epithelium (RPE). AAVs...
  10. Viral Vectors 101: The Retroviral Lifecycle

    Type
    Blog Post
    ...synthesized inside of what is called the “target cell” (or host cell) by the viral protein reverse transcriptase...reverse-transcribed DNA into the host cell’s genome and then use cell machinery for transcription and translation...1971). Noninfectious ARK mouse embryo cell lines in which each cell has the capacity to be activated to ...tools in molecular biology. “Retroviruses” is an umbrella term which encompasses 1.) the gamma-retroviruses...gamma-retroviruses have their own unusual sort of virulence as well — namely that they can cause cancer via insertional..., interested in transferring genes to mammalian cells (i.e. transferring DNA), yet retroviruses are RNA-containing...separate set of instructions in the same producer cells as the virus. Because it is made at the same time...
  11. Minigenomes - a Safe Way to Study Dangerous Viruses Like the Ebola Virus

    Type
    Blog Post
    ...choose cell lines that are highly transfectable.  The amounts of each plasmid transfected into cells are ...100 ng L, and 2 μg minigenome plasmid per well (in a 6 well plate format). However, since plasmid quality... polymerase gene or using cells that stably express T7 (e.g. BSR T7/5 cells) (1). We hope that minigenomes...capable of being replicated and transcribed in the cell when the appropriate viral proteins are provided... RNA-dependent RNA polymerase into the infected cells. The EBOV polymerase replicates the viral genome...on separate plasmids and are co-transfected into cells alongside a plasmid encoding the minigenome. These...transcribed (and the viral mRNAs are translated) by cellular machinery. NP encapsidates the negative sense,...
  12. Cpf1: A New Tool for CRISPR Genome Editing

    Type
    Blog Post
    ...new class 2 nuclease, Cpf1 (CRISPR from Prevotella and Francisella), was annotated in several genomes and...orthologs that display cleavage activity in mammalian cells. Like Cas9 nucleases, Cpf1 family members contain...one to characterize the Cpf1 nucleases. Using Francisella Cpf1 (FnCpf1), they employed an E. coli plasmid...GC-content. After sequencing and searching for cellular RNAs important for Cpf1 function, they found that...the PAM. With this information, they turned to a cell culture system to see if any Cpf1 nucleases would...would exhibit in vivo activity in mammalian cells. From 16 diverse Cpf1 candidates, Zetsche et al. found...particularly helpful for targeting non-dividing cells, which are difficult to modify through homology-...
  13. Finding Your Science Policy Path

    Type
    Blog Post
    ...developed by Dr. Kelly Singel which provides an overview of all available science policy fellowships in federal...Steph Guerra, a AAAS Science and Technology Policy Fellow at the Veterans Health Administration. “But, seriously... a variety of science policy roles including fellowships, volunteer positions, and part-time opportunities...current work as a AAAS Science and Technology Policy Fellow (STPF) at the Veterans Health Administration, I...pursue regulatory approval for a new product or a well-endowed philanthropy who can shift the funding landscape...compiled by the AAAS Science and Technology Policy Fellowship Program to learn more about where science policy...policy? Many science policy training programs and fellowships have a strong focus on early career researchers...
  14. Neuronal labeling with Spaghetti Monster

    Type
    Blog Post
    .... FPs are generally bright, stable and well tolerated by cells. They can be used for protein localization...of neuronal sub-cellular structures GFP is limited in its ability to label subcellular structures in the...ability to interact with protein partners within the cell. However, antibodies can have low affinity for these...trigger protein aggregation which is toxic for the cells and affects the labeling of small structures like...team, an ideal probe should combine the solubility, cell tolerance, and optional fluorescence of FPs with...is a symbol of opposition to the teaching of intelligent design in public schools and was started in 2005...used to amplify the direct smFP signal within sub-cellular structures. For instance, smFPs have been used...
  15. Visualizing Genomic Loci with CRISPR-Sirius

    Type
    Blog Post
    ...The catalytically dead Cas9 protein (dCas9) is well known for its ability to bind DNA targets without... to date for visualizing genomic loci in living cells. Previous iterations of genomic loci visualization...labeling system to visualize chromosomal loci in human cells (Ma et al., 2015). To do so, they fused a different...different hairpins will produce a secondary color (yellow, cyan, or magenta) depending on the hairpin combination...visualization of sites on different chromosomes in living cells, the system requires high-copy chromosome-specific... aptamer system to visualize the gRNA in living cells. Broccoli aptamers are nucleic acid sequences that...production needed to deliver CRISPR-Sirius into cells. They named this guide sgRNA-Sirius-8XMS2 which ...
  16. Reagent Repositories Are Speeding up Science During the Pandemic

    Type
    Blog Post
    ...4,000 cell lines. Seventeen of these cell lines were used to investigate the susceptibility of cells from...additional cell line used in this study came from the Japanese Collection of Research Bioresources Cell Bank...that SARS-CoV, which entered human cells via hACE2, could not enter cells expressing murine ACE2 (Subbarao...repositories that distribute mouse strains, plasmids, cell lines, and much more have been critical for pandemic...from Reproducibility for Everyone. Case study 1: Cell lines Many of the reagents used to investigate SARS-CoV...accelerating research into this virus. One such example is cell lines. The American Type Culture Collection (ATCC...of this pathogen. The sharing and distribution of cell lines from repositories on opposite sides of the...
  17. Hot Plasmids - January 2023

    Type
    Blog Post
    ...mCherry for FACS sorting of the weaponized T-cells (CAR-T cells) - and then delivering them to a tumor - ...effectively as standard CAR-T cells, but it reduces the off-target effects caused by T cell migration.  CAR expression...Adapted from Fig. 2 Campbell et al, Nature Methods   Find YFP plasmids here!   Campbell, B.C., et al. Chemically...reducing the on-target off-tumor activity of CAR–T cells was recently devised by the Yingxiao Wang lab.  ...above can be made for expressing your favorite T-cell receptor, or perhaps any other tool that can benefit...  Wu Y, et. al. Control of the activity of CAR-T cells within tumours via focused ultrasound. Nat Biomed... is that some antibodies may just not perform as well in one application as another, so it is always best...
  18. Hot Plasmids - February 2022

    Type
    Blog Post
    ...-binding scFv onto a well-folded scFv scaffold to improve its stability in cells, and use it in a variety... including live-cell imaging, single-molecule tracking, immunolabeling of fixed cells, Western blotting...possibilities in both cell engineering and gene therapy.  Xiaoshu X, et al. Molecular Cell. 2021. https://doi.org...Anti-FLAG Frankenbodies for modular imaging of cellular targets Optimized genetic screening technique ...Anti-FLAG Frankenbodies for modular imaging of cellular targets by: Mike Lacy Adding to their set of anti-HA...frankenbodies to amplify the signal.  Liu et al. Genes Cells. 2021. https://doi.org/10.1111/gtc.12893, Zhao et... Cas12a for multiplexed gene perturbation by: Gabrielle Clouse While many CRISPR-based genetic screening...
  19. With an Eye Towards the Future, We Look Back at the March for Science

    Type
    Blog Post
    ...training, so of course I felt compelled to participate in one of the satellite Marches for Science (my local...currently a post-doctoral fellow at Vanderbilt University. She studies beta-cell function and failure in... duty to tell our science stories in a manner that encourages open discourse with our fellow community...also incredibly impressed with how well organized the march was, as well as the friendly atmosphere that ...constant vigilance and actions beyond marches, as well as allies outside the scientific community. Vanessa...responsibility to join the public conversation and to tell the stories behind our research.  That's why I marched...against legislators and because the march had been so well-publicized, we might encounter hostile anti-science...
  20. Plasmids 101: Modular Cloning Applications and Kits

    Type
    Blog Post
    ...can be used in bacterial and cell-free expression systems, mammalian cells, yeast, flies, and even plants...transport studies in HEK cells, recombinant protein purification in bacterial cells, and a two-hybrid protein...for synthetic biology applications in bacteria or cell-free systems. The approach is particularly useful...tags to your proteins, then the CIDAR Kit is an excellent option (Iverson et al., 2016). CIDAR offers a ...add-on kit and is compatible with E. coli and/or cell-free systems. Protein expression in yeast MoClo ...plant-specific parts you‘ll need, including sub-cellular localization signals, plant markers, and reporters...of expression and integration needed in mammalian cell types, and comes with a large library of common ...
  21. Choosing the B(right)est Fluorescent Protein: Photostability

    Type
    Blog Post
    ...intensity evolves over time in living cells at a power used for live-cell imaging. To conclude, the most photostable...molecule will photobleach at some point. For live-cell imaging, it is desirable to have fluorescent proteins...experiment. The best fluorescent proteins for live cell imaging can be excited many times, thereby producing...these factors, environmental conditions such as cellular redox state and oxygen concentration may affect...protein is a key requirement for quantitative live-cell imaging, it is important to be able to quantify ...it is advisable to perform time-lapse imaging of cells producing the fluorescent protein of interest under... a substrate. These in vitro methods allow for a well-controlled environment, but they do not mimic the...
  22. CRISPR Methods for Bacteria: Genome Engineering, CRISPRa, CRISPRi, Base Editing, and More

    Type
    Blog Post
    ...Leonard SP, Perutka J, Powell JE, Geng P, Richhart DD, Byrom M, Kar S, Davies BW, Ellington AD, Moran NA, Barrick...Control of Gene Expression. Cell 152:1173–1183 . https://doi.org/10.1016/j.cell.2013.02.022 Ronda C, Pedersen... is primarily a means of selection that targets cells in which homologous recombination has not occurred...ensures high editing efficiency; the only non-edited cells to survive have inactivating mutations in the Cas9... E. coli, the system was used successfully in Tatumella citrea, another species of Enterobacteriaceae,...one or more genes in E. coli. and in a mammalian cell line (Qi et al., 2013). Two important features of...other Cas9 orthologs to identify a more efficient, well tolerated, Cas enzyme. They identified the Cas9 ...
  23. Split Fluorescent Proteins for Studying Protein-Protein Interactions

    Type
    Blog Post
    ...measuring protein expression or localization in cells, or even single-particle tracking of the bound complex...) for use with GFP(11) Multiplexed labeling of cellular proteins with split fluorescent protein tags. ...(1-10) and GFP(11) Versatile protein tagging in cells with split fluorescent protein. Kamiyama et al. ... and mNG3A(1-10) for use with mNG2(11) Improved yellow-green split fluorescent proteins for protein labeling... S, Brown D, Huang B. PLoS One. 2020 Bo Huang Yellow Venus pBiFC-VN173, pBiFC-VC155 Identification of...pairs with sfCherry2(11) Multiplexed labeling of cellular proteins with split fluorescent protein tags. ...
  24. The AAVantages of AAV in CRISPR Screens

    Type
    Blog Post
    ...same: Deliver CRISPR library to cells of interest. Select for cells of interest (positive or negative...infect specific cell or tissue types. Using serotypes that have a known tropism for your cells of interest... a host cell’s genome. In this state, AAV cargo can be stably expressed in non-dividing cells for long...mice are involved. Ex vivo starts with transducing cells with the CRISPR library in vitro before transplanting...interest — for example, AAV8 for kidney cells — can help improve infection rates in your experiment. ...AAV vectors, enhancing their affinity for specific cell and tissue types. The combination of serotypes and...integration sites seem to only occur in the target cells or tissues. AAV also shows improved transduction...
  25. Pooled Library Amplifications

    Type
    Blog Post
    ...Genome-wide Inhibition Library. DNA and cell amounts After deciding on a cell type, you will need to determine...DNA and how many cells to use for your transformation(s). The amount of competent cells you need total ... depending on the particular type of cells you are using, as well as other factors, such as your lab’s...generalized amplification protocols tend not to work as well.   Defining your library First, you’ll need to collect... generally electroporated into electrocompetent cells to ensure the highest possible transformation efficiency...efficiency. Using Stbl4 or other ultra-high efficiency cells ensures that plasmid diversity in the library is...transformations, such as splitting 400 ng of DNA in 100 μL of cells over four individual electroporations. The specifics...
  26. Google Forums Round Up: First Impressions of NgAgo

    Type
    Blog Post
    ...degraded by the cellular machinery, leaving a small amount of active NgAgo/ssDNA complex in the cell. As proposed...results of Gao et al 2016 in a letter to Protein & Cell. Update (August 3rd, 2017) THE ORIGINAL NgAgo ARTICLE... guide, it cannot be produced from a plasmid in cells. Additionally, in vitro assembly of NgAgo/ssDNA ...dangerous, non-physiological temperature for mammalian cells and one which diminishes the endonuclease activity...guide. Therefore, researchers must co-transfect cells with 5’-P-ssDNA guides and an NgAgo expression plasmid.... Researchers can conveniently transfect/inject cells with in vitro preassembled Cas9/gRNA complexes or...lipofectamine-based method to deliver NgAgo ingredients into the cell, the same method used by Gao et al, 2016 (1). View...
  27. Plasmids 101: Optimizing Plasmid Yields

    Type
    Blog Post
    ...large amounts of carbohydrates that can inhibit the cell lysis process. To ensure that lysis is complete,...strains adapted for protein purification use the cell’s resources to produce high levels of protein, not...difference? In the simplest of terms, more volume = more cells = more plasmid. Plasmids can vary in copy number...of plasmid copies supported within each bacterial cell in your culture. Copy number is partially specified...richer media or adding supplements can improve your cell density, leading to an improved plasmid DNA yield... supplements to the media You can achieve higher cell density using a nutrient-rich broth such as Terrific...glucose (in moderation) may also serve to increase cell density and plasmid yield. Start with a single, ...
  28. Plasmids 101: Multicistronic Vectors

    Type
    Blog Post
    ...them. Why Use multicistronic vectors? Detecting cells that are expressing your gene, especially if you...reporters allow you to easily screen or select for cells that are expressing your gene of interest at high...promoter, multicistronic plasmids ensure that any cells that are positive for your marker should also be...anytime you want to express multiple genes in the same cell. Although it is possible to drive co-expression ...promotes translation of the viral genome in eukaryotic cells.1,2 Since then, a variety of IRES sequences have...discovered - many from viruses, but also some from cellular mRNAs. What they all have in common is the ability... cistron due to factors such as the experimental cell type and the specific genes cloned into the vector...
  29. What's New in CRISPR - March 2020

    Type
    Blog Post
    ...for studying the bacterial cell cycle, asymmetric cell division, and cellular differentiation, but it takes...crescentus Multiplexed gRNA for human pluripotent stem cells CRISPR-based DNA demethylation Optogenetic repressors...complex remains in the cytoplasm. Read the paper in Cellular and Molecular Bioengineering Find the optogenetic...Figure 1: Serial dilutions of CRISPRi in Caulobacter cells for ctrA gene expression using various dCas9. Image...popular Streptococcus pyogenes system does not work well in Caulobacter). To test their CRISPRi system, the...lab repressed ctrA, a gene encoding an essential cell cycle regulator. The lab expressed both dCas9 and...piggyBac transposon system for human pluripotent stem cells Lindy Barrett’s lab developed new fluorescently ...
  30. Three Key Considerations for Precise Neuronal Targeting Using AAV Technologies

    Type
    Blog Post
    ...Table 1 from the paper. 2. Manipulate your cell of interest: Cell-type specific expression of molecular tools...in their cell bodies. Optical stimulation in a different brain area can then reveal the cells bodies of...with AAV: 1. Getting your viral vector into your cell of interest: AAV tropism and route of administration...transduction, the viral capsid proteins bind to the target cell’s surface proteins and this interaction determines...efficiency of the AAV serotype used for a specific cell type. Find some transduction characteristics of ...by restricting expression to genetically defined cell types. Specific transgene expression can be also...different approaches can increase the specificity of cell targeting even further. For example, injecting AAVs...
Showing: 421 - 450 of 1024 results