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Showing: 181 - 210 of 858 results
  1. Plasmids 101: Control Plasmids

    Type
    Blog Post
    ...two types of replicate controls: technical and biological. In general, technical replicates can be thought... employ transfection, negative, positive, and replicate controls.  Transfection controls: empty vector...the interrogation of the independent variable. Replicate controls: technical and biological Reliable results...derived from one source. Conversely, biological replicates ARE independent and can be thought of as "reproducibility...reproducibility controls". Biological replicates are what makes up your sample size (aka your n value)"... provide more in depth information. Technical replicates An example of a technical control is the transfection...plasmid from the same aliquot/preparation. The replicate control isn’t measuring or assessing reproducibility...
  2. Scientific Reproducibility - Focusing on Solutions at the Minisymposium on Reproducibility

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    Blog Post
    ...someone has replicated it precisely. You can find a great discussion of different types of replication in Nosek...perfect story for a “high impact” publication can lead to the publication of rare flukes showing positive...adoption of policies that promote reproducible publishing practices. One example is the publication of peer...Wednesday we worked with the Harvard GSAS Science Policy Group to organize a Minisymposium on Reproducibility... out on the panel, irreproducibility undermines public trust in science and research. Nonetheless, I’d...difficult to publish so-called “negative” results that conflict with our original hypotheses. Looking for novelty...these positive results will be published. The publication record will then show that the tested hypothesis...
  3. Plasmids 101: Yeast Vectors

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    Blog Post
    ...recombination. Yeast Replicating plasmids (YRp):  These vectors contain an Autonomously Replicating Sequence (ARS...mammalian vectors, will catch you up on the core replication and resistance features of yeast vectors and ...includes but is not limited to: rapid growth, ease of replica plating and mutant isolation, a well-defined genetic...vectors must contain a yeast-specific origin of replication (ORI) and a means of selection in yeast cells...antibiotic selection markers.  The yeast origin of replication (Please note: This first section primarily pertains...ve also noted some features required for the replication of fission yeast, Schizosaccharomyces pombe, ...within a yeast vector determine how the plasmid is replicated and maintained within the yeast cell. These elements...
  4. Delivery Methods for Generating iPSCs

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    Blog Post
    ... to verify there’s no genomic integration Replicating EBNA1 episome Non-integrating Medium Medium ...creates heterogeneous iPSC cell lines, which can complicate comparisons made between lines. Incomplete silencing...Retroviruses are not considered safe for clinical applications.     Lentiviral: Lentiviral vectors infect dividing...unavoidable heterogeneity between clones. This can complicate comparisons made between samples, i.e. transgene...delivery is not considered safe for clinical applications. Excisable Cre-lox lentiviral vectors: This...is still not considered safe for therapeutic applications. piggyBac (PB) transposon: The PB transposon...express reprogramming factors for therapeutic applications. Sendai viral vectors: Sendai virus is a single...
  5. Hot Plasmids Spring 2024

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    Blog Post
    ... to test reconstitution via mRNA trans-splicing. A cis-splicing vector served as positive control (cis-ctrl... vector 2; BD, binding domain; SDS, splice donor site; SAS, splice acceptor site; pA, polyadenylation ...3’ long terminal repeats (LTR). The 3’ LTR is duplicated during lentiviral integration, producing a second...reused from Walton et al. 2024 under a CC-BY-NC-ND license. In this iteration, the size of the lentiviral...Image adapted from Yan et al. 2024 under a CC-BY license. Yan, J., et al. (2024) Improving prime editing...adapted from Serrano et al. 2023 under a CC-BY-NC-ND license.  Integrating hIBA1a promoter into AAV vectors...for microglia research and broader therapeutic applications.  Find microglia-targeting AAV plasmids here...
  6. Antibodies 101: Selecting the Right Antibody

    Type
    Blog Post
    ...your specific application. Consider also that there may be variations within an application. Take immunohistochemistry...website highlights a variation of your application, a publication successfully used it in a similar way...choosing an appropriate antibody first look at the application-specific data provided on the manufacturer’s ... a linear antigen tend to work very well for applications that denature a protein to its primary (linear...the most similar to yours. Take a look at the publications cited on the manufacturer’s website, which may...plan to. To secondary or not to secondary?  The application will also determine whether you should use an... as it will help to amplify the signal. Some applications use either direct (primary-conjugated) or indirect...
  7. A Control for All Seasons

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    Blog Post
    ...results.  Replicates Replicates are another critical control in biological experiments. Replicates can be...of biological replicates such as multiple mice in each group and C, technical replicates or repeated measurements...secondary antibodies.   Application-specific controls Some antibody-based applications have very specific ...then moving on to controls for antibody-related applications. After reading, you will have a better understanding... be able to confirm that the testing protocols elicited the expected response and have a baseline with...statistical power of an experiment. Technical replicates are repeated measurements of the same sample ...difficult to obtain meaningful results.  Biological replicates are distinct samples that are treated identically...
  8. Great Results Start with Great Standard Curves

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    Blog Post
    ... be run in duplicate or triplicate. The closeness of the data points generated by replicate values provides... the standard dilution series in duplicate or triplicate. Replicates allows you to calculate the curve... deviation of each replicate measurement divided by the mean of all the replicates multiplied by 100. ...regularly, and mix samples very well.  Use duplicates or triplicates to increase the accuracy of your experiment... critical for a number of popular scientific applications, and the quality of a standard curve can make...for an acceptable R2 but for many scientific applications users aim for an R2 above 0.95.    Additional...ideal %CV is less than 15%. You should also run replicates for all of the samples in the assay, as this ...
  9. Evolution of Brainbow: Using Cre-lox for Multicolor Labeling of Neurons

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    Blog Post
    ... recombination. In 2007, Joshua Sanes and Jeff Lichtman, both of Harvard’s Department of Molecular and...towards single-cell resolution imaging. Sanes and Lichtman endeavored to create a map of the brain, a connectome...constant inversion of the construct. Sanes and Lichtman used pronuclear injection to insert these Brainbow...table to the right); in various reports, Sanes and Lichtman have observed from 90-160 distinct colors due ...of farnesylated derivatives enables labeling of delicate axonal and dendritic processes not previously ...Between Brainbow Systems   Brainbow variants and applications beyond the mouse brain In addition to improving...improving the Brainbow system, Sanes and Lichtman also developed a complementary Flpbow construct that is ...
  10. Viral Vectors 101: Parts of the AAV Packaging Plasmid

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    Blog Post
    ...Rep78/68 play a key role in AAV genome replication. Replication initiates from the AAV genome ITRs on ...contains the proteins needed for the virus to replicate,  and the transfer plasmid which contains the ...aka the RepCap plasmid encodes two genes: the replication (rep) gene and the capsid (cap) gene. In wild-type...its products. Created with BioRender.com   Replication (rep) gene The rep gene encodes four proteins...proteins that are required for viral genome replication and packaging: Rep78, Rep68, Rep52, and Rep40. Rep gene...small (Rep52 and Rep40) Rep proteins. Alternative splicing generates the different C-terminal regions of ... domains, all four Rep proteins share a common helicase and ATPase domains. To function, the Rep proteins...
  11. DNA Purification Without a Kit

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    Blog Post
    ... DNA to silica columns, it’s bound to glass syringe filters. Normally DNA does not bind silica or glass...Regeneration of silica columns for DNA purification Starting material: PCR product or agarose gel slices Product...Before you reach for that silica spin column, stop to consider some ways to purify DNA without a kit....purification without a kit as well as one way to reuse silica columns from DNA purification kits. Kit-free alkaline...Starting material: bacterial cultures or agarose gel slices Product: plasmids or DNA fragments The plasmid ... with glass milk Starting material: agarose gel slices Product: DNA fragments You might be wondering, ...stick to the glass particles in glass milk, gel slices are first placed in a chaotropic salt sodium iodine...
  12. Sequencing Options for CRISPR Genotyping

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    Blog Post
    ...experiment is targeted amplicon sequencing. The information from targeted amplicon sequencing is highly ...have been widely adopted due to their relative simplicity and low cost. The problem with these assays is... genome for off-target sites irrespective of in silico prediction. These techniques differ in important...heterogenous populations, low sensitivity Targeted Amplicon Sequencing Provided 0.01% (variable) Sequence-...rate and the repair product sequence. Targeted amplicon sequencing doesn’t tell the whole story ...These strategies can be used in concert with in silico prediction to create a more comprehensive list ...unbiased detection isn’t as sensitive as targeted amplicon sequencing. For example, GUIDE-seq seems to have...
  13. CRISPR-based Genome Editing Systems For Editing in E. coli

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    Blog Post
    ...targeting the pMB1 replicon on pTargetF (Jiang et al., 2015). In addition to the pMB1 replicon, pTargetF contains...PrhaB, 2) changed the replicon of pCas into a non-temperature-sensitive replicon, and 3) added the sacB... the S. pyogenes Cas9, a temperature-sensitive replicon for self-curing, an arabinose inducible lambda-red... expression of the sgRNA that targets the pMB1 replicon, resulting in cutting of the plasmid. At this ... the gRNA on pCas that is specific to the pMB1 replicon of pTargetF may exhibit a more serious leaky expression...serve to interrupt genes (or gene clusters) in metabolic engineering. So far, we’ve used the MUCICAT system...when compared to the industrial strain. In our metabolic engineering case study of N-acetylglucosamine ...
  14. Improved Plasmid Maps Powered by SnapGene

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    Blog Post
    ...cutters. You can also sort enzymes by clicking on column heads. Clicking on a particular restriction enzyme...while the SnapGene powered map is on the right (click here to see the new map in action). Read on to learn...simple but powerful display improvements, when you click on any plasmid map, you also have the ability to...analyzer will allow you to dive into the details. Click on the “View all sequences” button to find all available...For more immediate, high-level analysis, you can click directly on the “Analyze Sequence” button to pull...Maps This is the first tab you’ll land on after clicking the “Analyze Sequence” button. The maps hosted...and a description of its function. You can also click one location in the plasmid and then a second location...
  15. Antibodies 101: Single Chain Fragment Variables (scFvs)

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    Blog Post
    ...led to their application for basic and translational research.  Basic research applications of scFvs: ...made up of glycine and serine with dispersed hydrophilic residues for increased solubility (Monnier et...blood clearance, which is useful for imaging applications; better tissue penetration which is useful for... for therapeutic and imaging applications; and reduced immunogenicity when administered in vivo due to...from blood can be a drawback for therapeutic applications where longer retention times often increase ...since it’s genetically encoded.   Translational applications of scFvs: Just like antibodies, there are many...2019).Many of the scFvs designed for oncology applications are reformatted as bispecific molecules which...
  16. Summer SciComm: Preprints

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    Blog Post
    ... and comment online! Want the general public (say, policymakers or community organizations) to use your...poster or talk, or submitting patent or grant applications; to informal settings like lab meetings, Twitter...scientific manuscripts shared by the authors on a public server independent from peer-reviewed publishing...accelerating science! Photo courtesy of under a CC license. Many scientists and advocates have argued ...increasingly growing time from submission to publication. It takes many months, often more than a year...avoid many of these issues, by sharing their work publicly and immediately once the manuscript is drafted...and updated by the authors over time, providing a public record of changes, critiques or endorsements. In...
  17. Science Communication Snapshot: DayCon 2015

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    Blog Post
    ...Organizing a science conference for the public How does one organize a public scientific conference? As a member...DayCon is a one-day conference aimed at the general public that provides an accessible introduction to various...the communication gap between scientists and the public and help make science more transparent. Second,... their communication skills and engage with the public. The organization runs a wide variety of programs...conference-style experience that was accessible to the general public both in terms of cost and content level. Sponsorship...science outreach can be, both for scientists and the public. For students, these opportunities to improve our... alternative careers in science. In return, the public receives trustworthy, intelligible scientific resources...
  18. Open Resources and Plasmid Tools For Studying C. elegans

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    Blog Post
    ...the OpenWorm website. microPublication microPublication is a unique publication for the worm community...into larger publications and would otherwise be lost in lab notebooks forever. microPublications are peer-reviewed...aims and approach of CeNGEN, check out their publication.   3’UTRome The 3’UTRs of mRNA are important ...normally one figure and can be negative and/or even replicated studies to show reproducible results. This a ...referenced. In addition the data published in microPublications is curated and added to other databases including...including wormbase and flybase. microPublication is run and maintained by members of the worm community...introducing point mutations that was published in a microPublication (Schwartz and Jorgensen, 2018).  These are...
  19. Early Career Researcher Toolbox: Finding Relevant Papers

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    Blog Post
    ...searches, such as clicks to read the abstract or full text of the paper, publication date, a relevance...show all publications by an author, total number of citations, and the number of publications that heavily...that term. You can also set up alerts for new publications from a particular author. Saving papers Papers... work, so it’s also a good place to look for publications. Bonus: papers have to be summarized in 280 ...organizations, and universities often tweet about publications in the fields of research they support. Monitoring...Artificial Intelligence. Semantic Scholar analyzes publications and figures using machine learning to extract...your search to a specific window of time for publication. To help you quickly identify papers with greater...
  20. Antibodies 101: Choosing the Right Isotype

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    Blog Post
    ...your experiment (all well validated for your application, of course!) When the stars are aligned and the...factors that affect isotype choice. Target and application should be considered The first question you may... a strong signal and to work in a variety of applications. The desired specificity of your secondary antibody...affect my experiment?” Well, it depends on the application and target. If you are running a basic western...target is expressed at very low levels or your application requires a high degree of affinity, then species...considered when choosing an antibody. In some applications probing species-on-species, i.e. using a mouse...mouse IgG2a and rat IgG1 antibodies in the same application, using a Goat anti-mouse IgG2a cross-adsorbed...
  21. CRISPR 101: Epigenetics and Editing the Epigenome

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    Blog Post
    ...epigenetic modifications across the genome) has been implicated in disease states, and targeting the epigenome...to specific DNA sequences. Non-editing CRISPR applications direct catalytically dead dCas9 fused to a variety...small DNA methyltransferase from the prokaryote Mollicutes spiroplasma (M. Sss1) (termed MQ1.) The Q147L...doi.org/10.1038/nbt.3199 Find plasmids from this publication at Addgene. Klann TS, Black JB, Chellappan M...doi.org/10.1038/nbt.3853 Find plasmids from this publication at Addgene.  Lei Y, Zhang X, Su J, Jeong M, ...10.1038/ncomms16026 Find plasmids from this publication at Addgene. Liu XS, Wu H, Ji X, Stelzer Y, Wu.../j.cell.2016.08.056 Find plasmids from this publication at Addgene. Maeder ML, Angstman JF, Richardson...
  22. Magnetic Control of Proteins: More than a Dream

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    Blog Post
    ... tools for familiar applications. But how does one invent a tool for applications that don’t even exist... Andrew York, Maria Ingaramo, and their team at Calico Life Sciences recently set out to do just that ...phenomenon, improve the tool, and develop new applications for magnetoresponsive proteins. Motivated by...organisms) are opaque, which makes most biomedical applications of these tools difficult or impossible. But ...tool with magnets would enable new research and applications that don’t yet exist, but it wasn’t clear that...reproduced from Frank Hayward et al. 2024 under CC-BY license. They did more experiments to see if any small...reproduced from Frank Hayward et al. 2024 under CC-BY license.   Video 1: Fluorescence movie of E. coli ...
  23. Antibodies 101: Validation

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    Blog Post
    ...intended application - Remember, just because your antibody performs as expected in one application does ...strategies for antibody validation in different applications. Here, I want to highlight the general suggestions...intentionally generalizable and not specific to certain applications or antibody targets. That said, not every strategy...will be suitable for every antibody or every application. The goal is to show that your antibody has been...strategy to use will depend on your intended application and available resources.     Figure 1...confident in your data. This is a good option for applications like immunohistochemistry on human tissues, ...alternative translation start sites or alternative splicing that could lead to some form of the target protein...
  24. Live and Let Dye: Self-Labeling Protein Tags

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    Blog Post
    ...Few Complicated Non-natural amino acids 1 Various Many Complicated   Applications Organic...labeled through click chemistry. Although these multi-component systems can be complicated to implement,...having to clone a whole new construct for every application. Plus, the photophysical properties of chemical...advantages over fluorescent proteins, opening up new applications.   Figure 1: Live-cell labeling strategies...adapted from (Bottanelli et al., 2016) under CC-BY license. Combining orthogonal self-labeling tags on...self-labeling tag and a fluorescent protein) enables applications like multi-color imaging (Figure 2). If you’...reused from (Ulrichs et al., 2023) under CC-BY license.   But these tags aren’t limited to fluorescent...
  25. CRISPR Antimicrobials

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    Blog Post
    ...suppliers, and public health and medical organizations are working to help educate the public about proper...containing a phage origin of replication that can be packaged into replication-incompetent phage particles...Beisel et al., licensed under a Creative Commons Attribution 4.0 International License.   Improving...essential processes: cell wall synthesis, DNA replication, or protein synthesis. Because they target such...mammalian viral vectors in that the vectors are replication-deficient. Thus, a very large number of phagemids...CRISPR antimicrobials combines them with both replication-competent phages and antibiotics. Phage therapy...bacterial host range. To further potential clinical applications, Ando et al. recently engineered synthetic phages...
  26. pSiM24: Simplifying Plant Genetic Engineering

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    Blog Post
    ...for both transient and stable gene expression applications in plants. This smaller, easily customizable...Agrobacterium are termed binary vectors because they must replicate in two species: Agrobacterium and E. coli. Like.... coli. However, they also need to be able to replicate in Agrobacterium to ensure that they are maintained... Thus, binary vectors contain two origins of replication, one each for E. coli and Agrobacterium, along...bases each. By switching the E. coli origin of replication and codon-optimizing the Agrobacterium ORI, they...constitutively active M24 promoter has been modified with duplicated enhancer domains and characterized in studies...these properties of pSiM24 are suitable for many applications, the plasmid can also be customized due to its...
  27. The Open Repository of CRISPR Screens: CRISPR Screen Data in One Place

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    Blog Post
    ...list of individual screens curated for the publication. Clicking on the screen name takes users to a display...favorite gene was described in a CRISPR screen publication. You see this mentioned in the results section...manually curated and annotated from more than 45 publications, beginning with the seminal research articles... makes it possible for researchers to query all public CRISPR results for any gene of interest. In addition...screen curated in ORCS is linked to the original publication via its PubMed identifier, which can also be ...screens of interest.   Figure 3: Each publication featured in BioGRID ORCS has a dedicated summary... supplemental data tables available with the publication are also provided for the user. This approach...
  28. Hot Plasmids - November 2023

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    Blog Post
    ...for your application. Image reused form Doman and Pandey et al., 2023 under CC-BY 4.0 License. Find... CreVLPs, and eVLPs for in vivo and in vitro applications.   Figure 2: Modular features of DIRECTED...Strebinger et al., 2023, reused under CC-BY 4.0 License. Importantly, even commercial antibodies can...approach for experimental therapies and medical applications.  Find DIRECTED plasmids here! Strebinger, D...interactions or map a local proteome, but some applications have been challenging or inaccessible. The Ting...alkyne-phenol, to label proteins with an alkyne group for click chemistry reactions instead of biotin — a valuable...from Lin et al., 2023 bioRxiv, under CC-BY-NC 4.0 license. This system provides a unique new way to record...
  29. Illuminating Choices: A Guide to Selecting Fluorescent Dyes and Ligands

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    Blog Post
    ...emission wavelengths, which are pivotal in their application in biotechnology (Grimm & Lavis, 2022). These... substrates/peptides and antibodies. Example applications of this include coupling to an antibody, whereby...typically bind to. Stability of fluorescence: For applications that involve ranges of pH, and significant lengths...light, is another factor to consider. If your application requires longer periods of exposure, you’ll want...have shown that different fluorescent ligands can elicit varying degrees of β-arrestin-2 recruitment to ...descriptions, or technical manuals. Specific applications and matching dye/ligand choices For effective...beyond the diffraction limit of light. Dyes like silicon-rhodamine or Janelia Fluor (JF) dyes have specific...
  30. 27 Hot Plasmids from 2016

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    Blog Post
    ...to disparate physiological effects and complicate any metabolic study. The Ralser lab has created a unique.... Seeliger MA, Young M, Henderso MN, Pellicena P, King DS, Falick AM, and Kuriyan J. Protein Sci. 2005...brief articles highlight the main features and applications of a partiular plasmid or set of plasmids. We...Wu Lab library can be found in the associated publication. Ma, et al. Cell Rep. 2015. PubMed PMID: 26190106...and ubiquitous reporter assay. In their recent publication, Kroeze et al. describe their enhanced TANGO .... Each gene was chosen to represent the primary splice variant in 38 types of human cancer. Many of the...Sanger sequencing, respectively. The speed and simplicity of GMAP allows scientists to easily design, generate...
Showing: 181 - 210 of 858 results