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Showing: 181 - 200 of 862 results
  1. RUBY-Red Siliques

    Type
    Blog Post
    Published
    March 1, 2022, 2:15 p.m.
    ...Selectable transgene markers for plant transformation fall into two main categories: antibiotic/herbicide...presence of a transgene instead, which can’t be done if your selection method kills the transgene free individual...Arabidopsis seed following floral dip transformation next to an untransformed seed from the same plant beginning...resistance genes usually involves killing the untransformed seedlings or callus (undifferentiated plant ...For example, with CRISPR-Cas9 gene editing, transformation may be identified by resistance to an antibiotic...antibiotic. Successful editing of transformants then typically occurs in T0 plants (from callus) or T1 plants...contaminate it. I have used it for selecting transformation events and am currently planning to use it ...
  2. Antibodies 101: ELISA (Enzyme-linked Immunosorbent Assay)

    Type
    Blog Post
    Published
    Aug. 24, 2021, 1:15 p.m.
    ... the reaction of HRP with its substrate, 3,3′,5,5′-Tetramethylbenzidine (TMB). The addition of hydrochloric...coating the bottom of the well), and then its concentration is detected through visualization of an enzymatic... molecule, such as biotin. Next, a conjugated substrate is added to the wells. In the case where the detection...enzyme horseradish peroxidase (HRP). Finally, the substrate of HRP is added to the wells. This reaction produces...produces a colorimetric reaction that reflects the concentration of your target protein in each well. The reaction...Sandwich ELISA to quantitatively measure protein concentration or antibody specificity via a colorimetric reaction...Competitive ELISA to quantitatively measure protein concentration or antibody specificity via a colorimetric reaction...
  3. The MTA at Addgene

    Type
    Blog Post
    Published
    July 23, 2024, 2:17 p.m.
    ...the material transfer agreement, read on!  What is the MTA?  An MTA is simply a contract or agreement...Biological Material Transfer Agreement (UBMTA) is one of the most commonly used ones for transfers between academic...shine.  These types of agreements allow for centralized tracking when biological reagents are shared — both...for more information. Happy transferring!    Many thanks to our Tech Transfer team members Maura Coughlin...Addgene, then you’ve been involved in the material transfer agreement (MTA) process. Even though this process...the creation of a standardized agreement on the transfer of biological materials in 1995: the UBMTA. Because...most academic and nonprofit institutes, the Tech Transfer department is responsible for managing research...
  4. R Bodies: Membrane-Rupturing Microscopic Tools

    Type
    Blog Post
    Published
    April 14, 2016, 2:30 p.m.
    ...endocytosis, vesicle trafficking, or muscle contractions) are produced by orchestrated movements of networks...explore their ability to penetrate other barriers (like vasculature or extracellular matrices) in response...PMID: 3759909. PubMed Central PMCID: PMC213417. 2. Schrallhammer, M. et al. Tracing the role of R-bodies...learn a lot from Nature’s simpler solutions to transmitting forces over long distances. For instance, how...machines R bodies can repeatedly extend and contract in response to changing pH, and they can rupture...
  5. Harnessing Bacterial Toxins for Allelic Exchange

    Type
    Blog Post
    Published
    Aug. 15, 2019, 12:30 p.m.
    ...rhamnose-inducible promoter, though Khetrapal et al. also demonstrated that the arabinose promoter worked...strong transcriptional terminator BBa_B1002 (from IGEM) upstream of the MCS to reduce transcriptional readthrough...Channarasappa, and Howard M. Salis. "Translation rate is controlled by coupled trade-offs between site accessibility.... PubMed PMID: 23360965. PubMed Central PMCID: PMC3748948.  Khetrapal, Varnica, et al. "A set of powerful...rely on exogenous enzymes, require multiple transformation and plasmid curing steps, and can generate ...toxins to facilitate efficient recombineering (Khetrapal et al., 2015). They created vectors for Lambda...tight (Giacalone et al., 2006). The Chen lab demonstrated excellent counter-selection which enabled very...
  6. SARS-CoV-2/COVID-19 Detection Methods Based on CRISPR/Cas

    Type
    Blog Post
    Published
    May 5, 2020, 1:15 p.m.
    ...and to do so, the WHO recommends one strategy: testing, tracking, and social distancing. With countries...are designed, each binding to one strand of the reverse-transcribed target sequence that are present close... the samples. First, RNA is extracted and subject to reverse transcription. This is then amplified by ...PCR using Taq Polymerase and then transcribed to provide RNA substrates for Cas13. Cas13, upon finding complementarity...block and 62°C heat block Approach: Viral RNA is extracted and subject to isothermal amplification by primers...cleaves the supplied fluorescently labelled ssDNA substrates. Upon cleavage, the fluorescence is no longer...directly using saliva without having to perform RNA extraction but that may work only if there is a high enough...
  7. Thoughts on the Future of Research 2015 Boston Symposium

    Type
    Blog Post
    Published
    Nov. 25, 2015, 4 p.m.
    ...benefits commensurate with work training and experience, better align trainee expectations with job outcomes...that fact that training in the academic research environment is setup to prepare trainees for further work...non-academic careers, much of the training they receive as postdocs is not transferrable to other environments. ... of trainees at low wages will still be there without restructuring. Positive Points for Trainees - Taking...information - all traits you are likely to find in graduate students and postdocs. Trainees however, need ... the mentor and this training is clearly not equitable to that of other trainees despite the fact that...temporary and defined period of mentored advanced training to enhance the professional skills and research...
  8. Viral Vectors 101: Viral Applications

    Type
    Blog Post
    Published
    April 13, 2023, 1:15 p.m.
    ...Viral delivery is attractive due to the ease of transduction in difficult-to-transfect cell types ranging...higher than traditional transfection and random genomic integration of a plasmid. Viral transduction is also...overexpression of all human transcription factors, barcoded libraries to trace cell lineage, and so much...delivered with viral vectors instead of a traditional transfection method. This is because viral systems ...integrated into the genome of the target cell or transiently expressed. It’s important to note that for all...vector can express your construct in target cells transiently or constitutively depending on the virus used...also generally less toxic to cells than transfections, preserving cell viability. Library delivery Screening...
  9. Droplet Digital PCR for AAV Quantitation

    Type
    Blog Post
    Published
    Jan. 16, 2020, 2:18 p.m.
    ...droplets is used to calculate the concentration of the sample. This concentration can then be used to calculate...possible to measure the concentration of multiple targets simultaneously. For AAV titration, you should only ...tool for quantifying AAV for some time now. When titrating AAV by qPCR, viral DNA is amplified and monitored...For these reasons, we are in the process of transitioning our titering method from qPCR to ddPCR. Droplet...needed for your PCR experiment. The process to titrate AAV by ddPCR begins with diluting the virus. It...million.  After making the dilutions, they are transferred to a new plate containing the mastermix which...place.  When the PCR is complete, a droplet reader extracts the droplets from the plate and measures the fluorescence...
  10. 15 Hot Plasmids from 2017

    Type
    Blog Post
    Published
    Jan. 9, 2018, 3:02 p.m.
    ...energy transfer) and FLIM (Fluorescence Lifetime Imaging Microscopy) applications. To demonstrate the power...caging technique to beautifully demonstrate light-dependent Gal4 transcriptional activation and Cre recombination...scientists to quickly and easily generate zebrafish transgenic lines to study neurobiology and neuorodgenerative... six fluorophores with nonoverlapping emission spectra (N- and C-terminal tags for mTagBFP, TagRFPt, EGFP...pluripotent stem cells) through the expression of transcription factors OCT3/4, SOX2, KLF4, and c-MYC is the... method for generating iPSCs to express the transcription factors from a polycistronic cassette. However...comparable experimental results. Using PiggyBac transposons, the Woltjen Lab compared different variants ...
  11. Easi-CRISPR: Generating Knock-In and Conditional Mouse Models

    Type
    Blog Post
    Published
    April 5, 2018, 12:42 p.m.
    ... Wenning Qin. Single-stranded DNA repair templates Short single-stranded DNA templates have been shown...HDR subpathway. It's traditionally been difficult to produce long single-stranded DNA, but Miura et al...perform in vitro transcription, and use the IVT product as a template for reverse transcription to create your...order to insert two loxP sites. Since two double-strand breaks are made, it is common to see deletions ...structure. Today, multiple companies offer long single-stranded DNA production services or kits, including the... the separated guide RNA components (crRNA and tracrRNA) for maximum Easi-CRISPR efficiency. Easi-CRISPR...microinjection and electroporation methods using in mouse transgenics. Designing an Easi-CRISPR knock-in allele To ...
  12. Avoiding the Dark Side of Fluorescent Protein Fusions with mOX FPs

    Type
    Blog Post
    Published
    Oct. 27, 2015, 3 p.m.
    ...via the Sec translocon." Traffic 12.5 (2011): 543-548. Pubmed PMID: 21255213. Pubmed Central PMCID: PMC3079558...[3]. You must therefore determine your cloning strategy and decide whether you will create an N- or C-...mitochondria, lysosomes or they are secreted into the extracellular milieu. Many of the resident proteins within...these compartments undergo significant post-translational modifications including glycosylation, disulfide... addition of N-glycans [9]. Both of these posttranslational modifications can disrupt FP folding rendering...and yellow moxFPs. The inherent brightness and spectral characteristics of the moxFPs are comparable to...non-optimized parental proteins. Our recent publication illustrated the quantitative increase in fluorescent signal...
  13. Hot Plasmids May 2018 - Optogenetics, Decaffeination, Biosensors, and Fluorescent Protein Tools

    Type
    Blog Post
    Published
    May 15, 2018, 12:43 p.m.
    ...changes in intracellular Ca2+ levels than the original version containing CRY2 without the extra peptide....-free drinks. Finally, they demonstrated that the caffeine concentrations in several beverages could be...networks. A major drawback of this method is the stray excitation of neighboring neurons in opsin dense... (Figure 1.) Moreover, the group was able to demonstrate that while illumination of neighboring cells ...expression in E. coli. This operon is under the transcriptional control of a strong constitutive promoter (... required enzymes, including a glutathione S-transferase homolog from a Janthinobacterium sp. Moreover...Moreover, a caffeine “addicted” E. coli strain expressing this operon can serve as a living biosensor for measuring...
  14. Nanoblades: Tiny CRISPR Ninjas for Genome Editing Difficult Cells

    Type
    Blog Post
    Published
    Sept. 26, 2019, 12:50 p.m.
    ...its ability to infiltrate cells. Options for CRISPR delivery include plasmid transfection, RNP electroporation...been used to increase retroviral transduction efficiency by neutralizing the charge repulsion between virions...results demonstrate that Nanoblades are a potential alternative method for generating transgenic mice strains...electroporation, and viral transduction; but these methods aren’t stealthy enough to gain access to some cells...Repair (HDR), CRISPR activation or repression, transgenic mouse line creation, and in vivo gene editing... non-replicative. Nanoblades are produced by transfecting the following four components into 293T cells... can also deliver Cas9 variants, such as a transcriptional activator dCas9-VPR, if these variants are ...
  15. Three Tips for Preventing Viral Plasmid Recombination in Your Samples

    Type
    Blog Post
    Published
    Sept. 14, 2021, 1:15 p.m.
    ...Pick the right strain While common E. coli strains like DH5-alpha are recA-, some strains have been engineered...suggest gel extraction to isolate the full, intact plasmid. Please see our gel extraction protocol for...Learn about the common lab E. coli strains Find tips for viral transduction  ...Repeating sequences within a plasmid can undergo intramolecular DNA recombination. This naturally occurring...recombination, one resulting plasmid carries the transgene of interest (aka the viral genome) and the other...resistance gene and origin will replicate, and the transgene will be lost. Over time, bacteria containing the...further reduce recombination. Recombinase-deficient strains like Stbl2, Stbl3, and NEB stable E. coli reduce...
  16. Rewiring Metabolic Circuitry with CRISPR RNA Scaffolds [Video]

    Type
    Blog Post
    Published
    April 7, 2015, 4:21 p.m.
    ...biofactories by demonstrating the use of CRISPR-based RNA scaffolds to mimic natural transcriptional programs...recent paper, "Engineering Complex Synthetic Transcriptional Programs with CRISPR RNA Scaffolds." Adam has...visualize the concepts discussed in the paper. The transcriptional control of multiple loci is deftly coordinated...cerevisiae with few techniques that are easily transferrable across host species or metabolic pathways. A...synthetic RNA scaffolds that can recruit various transcriptional regulators (Zalatan et al. 2015).  These scaffolds...nucleotide sequence then subsequently recruit a transcriptional regulator to modulate expression at that locus...expression levels dependent upon the type of transcriptional regulator or the number of designed scaffold...
  17. Live and Let Dye: Self-Labeling Protein Tags

    Type
    Blog Post
    Published
    April 16, 2024, 1:15 p.m.
    ...activity and instead become trapped in a covalent bond with its substrate. Then, all it takes is a bit...range of useful molecules linked to that substrate. If the substrate was linked to, say, a chemical dye or...applications.   Figure 1: Live-cell labeling strategies. The green structure represents a fluorophore...a look at some popular self-labeling tools: Tetracysteine: The first reported chemical labeling tag, from... gets covalently linked to derivatives of its substrate O6-benzylguanine (BG) (Keppler et al., 2003). ...The Virginia Cornish and Michael Sheetz labs demonstrated in 2005 that proteins fused with E. coli dihydrofolate...be labeled with fluorescent derivatives of its substrate trimpethoprim (TMP-tag) (Miller et al., 2005)....
  18. "Build Your Plasmid": The Game - Play to Teach

    Type
    Blog Post
    Published
    July 17, 2018, 12:23 p.m.
    ...your strategy. I realized that similar types of thinking go into developing gene therapy strategies for...logic and strategy skills to apply those concepts and understand how therapeutic strategies work. Find...game. They had 35 minutes to develop a strategy and build a transfer plasmid that could be used to genetically... a win-win strategy. After each team presented, all students had to pick the best strategy and propose... This guest post was contributed by Marco Straccia, an Associate Professor at University of Barcelona...the University of Barcelona wanted to develop strategies to make our classes more practical and hands-...biology, microbiology, genetic engineering and strategic knowledge to solve a clinical disease case. As...
  19. CRISPR 101: Ribonucleoprotein (RNP) Delivery

    Type
    Blog Post
    Published
    Sept. 6, 2018, 12:02 p.m.
    ...:     Cells must be amenable to transfection or viral transduction     Appropriate promoters must be...expression     The requirement for Cas9 transcription and translation delays editing What are Cas9-gRNA ... studies in cells that are difficult to transfect or transduce. While using Cas9-gRNA RNPs may require...site of interest. This is commonly performed by transfecting cells with a plasmid, such as PX459, which encodes... often be used in cells that are difficult to transfect, such as primary cells. Using RNPs can also alleviate... are detectable at high levels shortly after transfection, and are quickly cleared from the cell via protein...from Alex Schier’s Lab. gRNAs can be in vitro transcribed from ssDNA, which can be generated by commercial...
  20. Technical Design of a Western Blot

    Type
    Blog Post
    Published
    Aug. 22, 2024, 1:15 p.m.
    ...Types of transfers Your transfer options are wet, semi-dry, or dry/electroblot. A wet transfer is the most... while semi-dry transfers require a semi-dry transfer cell. Dry/electroblot transfers only work in the...) steps to the transfer: you’ll need to pre-wet most PVDF membranes before the transfer and allow them...  Note that each type of transfer requires different equipment. Wet transfers can be done in an insert...strip/reprobe Semi-dry transfer Decreased efficiency Electroblot transfer Increased cost; decreased...strong as DTT, you’ll have to use different concentrations if you switch from one to the other.  Type ... 180 V, 30 minutes Good shelf life; runs at neutral pH (reduced protein alteration) Expensive buffers...
Showing: 181 - 200 of 862 results