Skip to main content
Addgene
Showing: 51 - 100 of 478 results
  1. Antibodies 101: Normalization and Loading Controls for Western Blots

    Type
    Blog Post
    Published
    April 8, 2025, 1:15 p.m.
    ...the resulting fraction is reported. Figure 2: Normalization with loading controls. Under each lane...control band is weaker in condition 1 than condition 2, the normalized values for the two conditions are ...opposite change in your loading control. Assumption #2: The loading control can be accurately quantified ...significantly lighter in “condition 1” than “condition 2.” By eye, the loading control appears about the same...) are smaller than the analogous green “condition 2” points by the exact same value. For the two solid...consider a different loading control. Assumption #2: The loading control can be accurately quantified ...factors we’ve covered in our previous blog posts (1, 2) on western blotting. If the abundance of your POI...
  2. Plasmid Preps: Different Purity, Different Quantities, Different Uses

    Type
    Blog Post
    Published
    June 16, 2020, 1:25 p.m.
    ...electrocompetent cells is minimal (picogram range). It can be extracted from small bacterial cultures (i.e. 2-3 ml...ratios measured at 260 and 280 nm should fall ~1.8 - 2 and give scientists an indication of purity versus...contaminants. The 260 and 230 nm ratios should fall ~2 - 2.2, and provide an indication of purity versus ...hydrochloride used during plasmid extraction. Figure 2: Use cloning grade DNA for direct cloning of your ...lipopolysaccharide of the cell wall of Gram negative bacteria like E. coli that affects tissue culture cell line viability...introduces transformation grade plasmids into a bacterial cell. Transformation grade DNA  Transformation is ...Figure 3: Need to introduce plasmids into mammalian cells? Use transfection grade DNA. Transfection is ...
  3. Hot Plasmids - October 2022

    Type
    Blog Post
    Published
    Oct. 6, 2022, 1:15 p.m.
    ...GEVIs (called ASAP 1 and 2), they found an indicator that is optimized for 2-photon imaging of voltages...challenges in 2-photon in-vivo imaging of voltage fluctuations. Image credit: Liu Z, et al. Cell. 2022.  ...suitable for in vivo optogenetic use.   Fig. 2: A) HcKCR1 is highly selective for K+ over other Na...slice of HcKCR1-EYFP and tdTomato expressed layer 2/3 neurons in mouse. C) Action potential frequencies...two-photon microscopy. Cell, 18, 3408 - 3425.e29. (2022). https://doi.org/10.1016/j.cell.2022.07.013.   ...specific for human c-myc proto-oncogene product. Mol Cell Biol. Dec;5(12):3610-6.(1985). doi: 10.1128/mcb.5.12.3610...
  4. Rosella: A Fluorescent pH-Biosensor for Studying Autophagy

    Type
    Blog Post
    Published
    April 13, 2017, 2:30 p.m.
    ...Table 2 for more details on the effect of pH on the fluorescent properties of Rosella.   Table 2: Effect...in yeast. Autophagy,4(2), 205-213. doi:10.4161/auto.5331. PubMed PMID: 18094608 2. Sargsyan, A., Cai, J...environment like the vacuole or lysosome. See Table 2 for a summary of what color fluorescence Rosella emits...fluorescence accumulates in the vacuole. See Figure 2 for an example of what fluorescence looks like for... Mammalian Autophagy Research. Cell,140(3), 313-326. doi:10.1016/j.cell.2010.01.028. PubMed PMID: 20144757...analyzing autophagy of cytosol and organelles in yeast cells. Autophagy (Greek for “self-eating”) is induced ...radio-labeled long-lived proteins as a proxy for autophagy. Cells are cultured with isotope-labeled amino acids for...
  5. Plasmids 101: Secondary Nanobody Toolbox

    Type
    Blog Post
    Published
    Feb. 27, 2018, 2:04 p.m.
    ...Journal of Cell Biology. PubMed PMID: 29263082 Find plasmids from this publication at Addgene. 2. Bates,...antibody has an antigen binding site for a total of 2 binding sites per antibody. C) IgG’s are big enough...enough that multiple labels (green circles in figure 2 below) can be attached to each antibody. But being...displacement Require separate incubation of 1° and 2° Must use different species and/or different IgG ...Greater resolution due to lower label displacement 2° incubation can be skipped by pre-binding to 1° ...a fluorescent tag and the target antigen to about 2 nm, which can lead to higher resolution for super-...subclass.   Express the Nanobody In Bacteria: Table 2 also has a link to the plasmid you’ll need to express...
  6. The Materials Science of Optogenetics Experiments

    Type
    Blog Post
    Published
    Sept. 17, 2015, 2:30 p.m.
    ...different steps and materials required for each [1, 2]. This protocol [3] provides, in exquisite detail,...stimulation         In the video above, Channelrhodopsin 2 (Chr2) has been expressed in the motor cortex of a...lasers are relatively cheap and will run you about $2-3,000/laser. However, an important caveat is that ... the light-gated cation channel, Channelrhodopsin 2 (ChR2), exists in several states: closed/light receptive...PMID: 21628464; PubMed Central PMCID: PMC3138296. 2. Sparta DR, et al. Construction of implantable optical...board, Jacqueline N Crawley  [et al]. 2012;Chapter 2:Unit2 16. doi: 10.1002/0471142301.ns0216s58. PubMed...Pharmacology and Optogenetics. Cell 162.3 (2015): 662-674. doi: 10.1016/j.cell.2015.06.058. Pubmed PMID: 26189679...
  7. Multiplexed Capture of Promoter-enhancer 3D Chromatin Structures Using CRISPR

    Type
    Blog Post
    Published
    July 2, 2020, 12:40 p.m.
    ...eGFP tag, and 2) gRNAs Number of loci targeted One Many Sample type(s) Cell lines Cell lines, primary...Expression system Stable cell line expressing 1) FLAG-biotin-tagged dCas9, 2) BirA, and 3) one or more...Originally published Dec 7, 2017 and updated Jul 2, 2020. Promoters may be the star of gene regulation...sequence targeted in the experiment. Figure 2: Comparing CAPTURE and CAPTURE 2.0.     Original...identified and the level of on-target enrichment. 2. Determining the spatial and hierarchical organization...Cytogenetics, 11. https://doi.org/10.1186/s13039-018-0368-2  Liu X, Zhang Y, Chen Y, Li M, Zhou F, Li K, Cao H... of cells (~5x107). Together, these two requirements prevent the use of CAPTURE with primary cells or ...
  8. CRISPR Between the Genes: How to Experiment with Enhancers and Epigenomics

    Type
    Blog Post
    Published
    Aug. 9, 2016, 2:30 p.m.
    ...for the 2+ million DHS sites. See below for further details. DNA is a 3D Fractal Figure 2: DNA compaction... we identified in step 2. The result is a heterogenous population of stem cells, usually housed in a single...: 1. Find Enhancers that have NANOG binding sites 2. Design a CRISPR screen to target and disrupt the ...NANOG enhancers 3. CRISPR out the enhancers from step 2. See which ESCs die or differentiate Step 3 reveals...expression for NANOG enhancers, we’re ready for step 2: design a CRISPR screen to disrupt these enhancers... for stem cells, or metastasized tumor cells, or alzheimers-affected neurons, or [your cell line of interest...critical to stem cell survival. Knowing which genes influence the survival of our cell culture is the foundation...
  9. Viral Vectors 101: The Retroviral Lifecycle

    Type
    Blog Post
    Published
    July 27, 2023, 1:15 p.m.
    ...that have been developed into retroviral vectors and 2.) a subclass of retroviruses called the lentiviruses...effectively. Retroviral structure   Figure 2: Structure of a retrovirus. Image re-used from Dong...Dong & Kantor, 2021 under CC-BY license. Figure 2 gives a detailed view of the structure of a retroviral...transfer of RT, which would actually occur in step 2 during uncoating. After uncoating, reverse transcription...one of the two strands’ DNA counterparts from step 2 will be integrated by the viral integrase protein ... Air. Environmental Science & Technology Letters, 2(4), 84. https://doi.org/10.1021/ACS.ESTLETT.5B00050...synthesized inside of what is called the “target cell” (or host cell) by the viral protein reverse transcriptase...
  10. Minigenomes - a Safe Way to Study Dangerous Viruses Like the Ebola Virus

    Type
    Blog Post
    Published
    March 17, 2016, 2:30 p.m.
    ...reviewed in 2, 5). The minigenome is capable of being replicated and transcribed in the cell when the appropriate...study aspects of the EBOV replication cycle under BSL-2 conditions (4). What is a minigenome?   The EBOV ...nonsegmented negative sense RNA viruses (reviewed in 2, 3). Other important components of the Zaire ebola...as it would for a full-length viral genome (Figure 2). While it is technically possible to encode all four...500 ng NP, 500 ng VP35, 100 ng VP30, 100 ng L, and 2 μg minigenome plasmid per well (in a 6 well plate ...PubMed PMID: 9847328. PubMed Central PMCID: PMC103829. 2. Conzelmann, K. K. "Reverse genetics of mononegavirales...choose cell lines that are highly transfectable.  The amounts of each plasmid transfected into cells are ...
  11. Cpf1: A New Tool for CRISPR Genome Editing

    Type
    Blog Post
    Published
    Oct. 14, 2015, 2:30 p.m.
    ...single RNA-guided endonuclease of a class 2 CRISPR-Cas system." Cell (2015). PubMed PMID: 26422227. Find ...Cpf1 is a single RNA-guided endonuclease of a class 2 CRISPR-Cas system. Figure from Zetsche et al., 2015...2015. How was Cpf1 found and tested? Class 2 CRISPR systems, including the type II Cas9-based system...employed by class 1 systems. A putative new class 2 nuclease, Cpf1 (CRISPR from Prevotella and Francisella... the 3’ end of the target sequence. Figure 2: Effects of (A) double and (B) single base pair gRNA-target...Find plasmids from this publication at Addgene. 2. Zetsche, Bernd, et al. "Multiplex Gene Editing by CRISPR–Cpf1...orthologs that display cleavage activity in mammalian cells. Like Cas9 nucleases, Cpf1 family members contain...
  12. Important Considerations When Using AAVs

    Type
    Blog Post
    Published
    June 13, 2017, 2:30 p.m.
    ...University of Manitoba due to their Biosafety Level-2 or 2+. Please Note: Despite the fact that AAVs themselves...Location (1): What tissue? Location (2): Where in the tissue/which cell type? Location (3): Traveling from...in very specific cell populations. Find Ready-to-Use Retrograde AAV Preps at Addgene 2) Comparison of genetically...long and stable expression (up to 9 months in mice [2]). Low Immune Response: Compared to other viral vectors...may be sufficient to overcome the transport issues. 2. Failure to plan (for storage) Is planning to fail...Therapy 15.10 (2007): 1740-1743. PubMed PMID: 17882145. 2. Zincarelli, Carmela, et al. "Analysis of AAV serotypes... tropism and axonal transport of AAV serotypes 1, 2, 5, 6, 8 and 9 in the mouse brain." PloS one 8.9 (...
  13. Fluorescent Proteins 101: Photoactivatable Fluorescent Proteins

    Type
    Blog Post
    Published
    April 25, 2017, 2:30 p.m.
    ...fluorescent state make them useful for 2-color imaging with green PA-FPs. Table 2: Properties of Selected Reversible...PA-FPs come in 2 flavours- monomeric and tetrameric. Tetrameric PA-FPS are better for whole cell imaging and... of proteins and cells." Science 297.5588 (2002): 1873-1877. PubMed PMID:12228718. 2.Subach, Fedor V.,... conventional FP imaging. PA-FPs are divided into 2 main categories - those with irreversible and reversible... forms of the chromophore which contribute to the 2 peaks of wtGFP’s excitation spectrum- a major 397 ... / N99K / S148L / I165V / Q167P / L169V / I203R) (2) and PA-mRFP1(S146H / I161V / I197H) (3) were derived...with two distinct wavelengths of light (see Table 2). The best known reversible PA-FP is the naturally...
  14. Screening for Successful Genome Editing with Digital PCR

    Type
    Blog Post
    Published
    March 30, 2017, 2:30 p.m.
    ... (details in [2]) and can be used to quantify rates of mutation in a bulk or single cell-derived genomic...resulting from non-homologous end joining (NHEJ) (2-5), depending on your desired genome edit. Since exploitation... have been reported for mismatch nuclease assays (2, 6, 7). Ability to distinguish between mono-allelic...assays, in addition to testing their performance (2). Remember that although digital PCR is a great screening...PMID: 24509632. PubMed Central PMCID: PMC4063274. 2. Findlay, S. D., Vincent, K. M., Berman, J. R. & Postovit... successfully analyzed gDNA from a few thousand cells from single wells of a 96-well plate without prior... that they are easily able to distinguish single-cell derived samples with mono-allelic mutations versus...
  15. Finding nucleic acids with SHERLOCK and DETECTR

    Type
    Blog Post
    Published
    April 16, 2020, 1 p.m.
    ...Diverse Class 2 CRISPR-Cas Systems. Molecular Cell 60:385–397 . https://doi.org/10.1016/j.molcel.2015.10.008...Endonuclease of a Class 2 CRISPR-Cas System. Cell 163:759–771 . https://doi.org/10.1016/j.cell.2015.09.038 Additional... can be used to diagnose the presence of SARS-CoV-2 RNA, but inadequate access to reagents and equipment...named this system SHERLOCKv2 for SHERLOCK version 2. Here are some of the improvements: SHERLOCKv2 uses... a protocol for using SHERLOCK to detect SARS-CoV-2 RNA. The test is started using RNA purified from patient...recently adapted the DETECTR platform to detect SARS-CoV-2 using a lateral flow strip format. They published ...CY (2020) CRISPR–Cas12-based detection of SARS-CoV-2. Nature Biotechnology. https://doi.org/10.1038/s41587...
  16. Sleeping Beauty Awakens for Genome Engineering

    Type
    Blog Post
    Published
    June 30, 2015, 2 p.m.
    ... of 2 components: 1) an SB transposase, the enzyme required for catalysis of transposition; and 2) a transposon...stable transgenic cell lines. Biotechnol J. 2015 Feb 4. doi: 10.1002/biot.201400821. PubMed. 2. Mates L, et... gene (red) for expressing the transposase enzyme.2.) The transposase enzyme is expressed (red stars) ...to infect and replicate in host cells, but they are susceptible to cells’ defense mechanisms. The use of... transposon; the plasmid is then degraded by the cell.4.) The transposase creates a double strand break...improve its gene insertion efficiency in primary cells. In 2009, Zsuzsanna Izsvak’s lab screened many SB...tranposase variants for hyperactivity in mammalian cells. Their efforts resulted in a new and improved SB...
  17. CRISPRainbow and Genome Visualization

    Type
    Blog Post
    Published
    Feb. 28, 2017, 3:30 p.m.
    ...Addgene. 2. Ma, Hanhui, et al. “Multicolor CRISPR labeling of chromosomal loci in human cells.” Proc. ...two genes over time, at a range of distances from 2-75 Mbp. Labeling multiple, intrachromosomal loci Building...successfully resolved loci with physical map distances of 2 and 75 Mbp, with the calculated fluorescent distances...established physical map. In comparing pairs of targets ~2 Mbp apart, they noticed that they could evaluate the...dCas9 supplied by a separate vector. Figure 2: CRISPRainbow generates 6 unique colors and a white...Genomic Loci in Living Human Cells by an Optimized CRISPR/Cas System.” Cell 155 (2013): 1379-1491. Pubmed...of 6 chromosome-specific loci in the U20S cancer cell line./ Each color represents a gRNA targeting a ...
  18. Plasmids 101: Modular Cloning

    Type
    Blog Post
    Published
    March 12, 2024, 1:15 p.m.
    ...TUs. Level 2: Assembly of multiple Level 1 TUs into multigene constructs. Figure 2: The three ...can be queried by testing any number in the Level 2 assembly. These pathways can require a lot of optimization... of multigene constructs. PLoS One. 2011 Feb 18;6(2):e16765. doi: 10.1371/journal.pone.0016765.  Hahn,... (2020). https://doi.org/10.1186/s12870-020-02388-2 Resources on Addgene.org Addgene’s Modular Cloning...complex cellular behaviors requires making complex manipulations to cells. For example: in a cell there ... yield a cellular phenotype, translational output, etc., which can support a larger cellular engineering...TU, or even an individual part, will behave in a cell. For unpredictable cases, MoClo provides two answers...
  19. CRISPR 101: Multiplex Expression of gRNAs

    Type
    Blog Post
    Published
    Sept. 10, 2020, 11:45 a.m.
    ...illustrated in the schematic below.   Figure 2: gRNA target sequences (colored rectangles) are cloned... plasmids: This plasmid set allows you to express 2-4 gRNAs, with four being the ideal number. First you...the total number of gRNAs you wish to clone, from 2-7. For example, if you’re expressing 4 gRNAs, you’...gRNAs into spectinomycin-resistant plasmids pX330S-2 to pX330S-(last gRNA number). The 5’ most gRNA is ...Multiplexing Plasmids: These plasmids allow you to assemble 2-4 gRNAs through Golden Gate or Gibson Assembly. gRNAs...Multiplex Plasmids: These plasmids allow expression of 2-5 gRNAs in zebrafish. Custom destination vectors are...and a subsequent curing protocol that requires only 2-3 hours incubation. Kondo Lab multiplexed base editing...
  20. Multiplex Genome Editing with CRISPR-Cpf1

    Type
    Blog Post
    Published
    May 9, 2017, 2:12 p.m.
    ...expression and needing to work with a transfectable cell line. 2) They require larger expression vectors which...Single RNA-Guided Endonuclease of a Class 2 CRISPR-Cas System. Cell,163(3), 759-771. PubMed PMID: 26422227...are also larger than their Cpf1 counterparts. Table 2. Cas9 Multiplexing Options  Multiplexing Method... Cpf1 expression vector.  See the graph in figure 2 for a comparison of editing frequency resulting from...Biotechnology 35.1 (2016): 31-34. Pubmed PMID: 27918548. 2. Zetsche, B., Gootenberg, J., Abudayyeh, O., Slaymaker... of 4 crRNAs in vitro and when expressed in 293 cells. This allows for a single promoter to drive expression... were used.  With transfection, 6.4% of HEK293T cells had edits at 4 of 4 targets when an array of 4 crRNAs...
  21. Antibodies 101: Designing Your First Flow Panel

    Type
    Blog Post
    Published
    May 28, 2024, 1:45 p.m.
    ...Table 2, Figure 5) for a hypothetical experiment in the lab. Let's say I am culturing HEK 293T cells in ... weak. Table 2: A simple flow panel to detect live, transduced, and CD45-expressing cells. Marker .... To understand why that is, let's look at Figure 2. The blue laser excites at a wavelength of 488 nm ... of PE's excitation spectrum (dotted line, Figure 2). The yellow/green laser, however, excites at 561 ... stronger — or brighter — signal.   Figure 2: Excitation and emission spectra for PE. The excitation...efficiency (eGFP expression).     The first item in Table 2 is a standard and should always be included—the live...from the other fluorophores to avoid bleeding and 2) BV421 is a very bright fluorophore, which makes it...
  22. Genome-wide Screening Using CRISPR

    Type
    Blog Post
    Published
    Aug. 18, 2015, 2:30 p.m.
    ...plasmid, or a 2-plasmid system in which Cas9 must be delivered separately.  Mutant cells are enriched ...diseases causing uncontrolled cell growth, such as cancer. Figure 2: The CRISPR library must be ...targeting a specific gene within the genome (see Fig. 2). Individual gRNAs are designed in silico using publicly...mouse, human, fly, E. coli, and T. gondii genes.  2) What genetic modification are you trying to make?...CRISPR libraries is a multi-step process (see Fig. 2). In most cases, CRISPR libraries are provided at ...heterogeneous population of mutant cells, with each cell or set of cells containing a mutation in a different...fluorescence-based cell sorting and screened for a particular phenotype. For example, mutant cells can be used...
  23. A Primer on Optogenetics: Introduction and Opsin Delivery

    Type
    Blog Post
    Published
    Sept. 10, 2015, 2:30 p.m.
    ...: PMC3337962. 8. Zhao S, et al. Cell type-specific channelrhodopsin-2 transgenic mice for optogenetic ...commonly used in optogenetics: 1) electrophysiology and 2) behavioral experiments. I’m not an electrophysiologist...choice in the brain region you wish to stimulate 2) Fabrication and implantation of the optical fiber...thoroughly elsewhere (here and here for instance) [2], [3]. Karl Deisseroth of Stanford University , one...reviews for a discussion of the different variants [1, 2, 4]. And, of course, the best way to learn about the...monitor expression at various time points (e.g. every 1-2 weeks over 8 weeks) in order to determine the optimal...(4):251-66. doi: 10.1038/nrn3171. PMID: 22430017. 2. Fenno L, et al. The development and application of...
  24. Five Popular Model Organisms, Part 2

    Type
    Blog Post
    Published
    Sept. 29, 2020, 1:15 p.m.
    ... H. J. (2009). Rats! Disease Models & Mechanisms, 2(5–6), 206–210. https://doi.org/10.1242/dmm.002733 ...are often used to study vertebrate embryology and cell development. One major resource for frog research...Organism to Study and Model Human Genetic Disease. Cells Tissues Organs, 205(5–6), 303–313. https://doi.org...
  25. Viral Vectors 101: Optogenetic Tools

    Type
    Blog Post
    Published
    June 27, 2023, 1:15 p.m.
    ...Optogenetic control of intracellular signaling pathways. Trends in Biotechnology, 33(2), 92–100. https://doi.org...for controlling neuronal activity, channelrhodopsin-2 (ChR2), a blue light-activated cation channel, from...used in tandem with the opsin.      Figure 2: Diagram of excitatory (ChR2) activation by light ...) domains, phytochrome B (PhyB), and cryptochrome 2 (CRY2) (Zhang & Cui, 2015). When stimulated with light...comparative analysis of microbial opsins. Nature Methods, 9(2), 159–172. https://doi.org/10.1038/nmeth.1808 References...comparative analysis of microbial opsins. Nature Methods, 9(2), 159–172. https://doi.org/10.1038/nmeth.1808 Nagel...Hegemann, P., & Bamberg, E. (2003). Channelrhodopsin-2, a directly light-gated cation-selective membrane ...
  26. Plasmids 101: Dimers and Multimers

    Type
    Blog Post
    Published
    Jan. 10, 2023, 2:15 p.m.
    ...identification.   Fig. 2: Gel image of Plasmid 61564: pBAMD1-2 (~4.7 kb) digested with SpeI and...to the formation of plasmid multimers. Cell. 1976 Dec;9(4 PT 2):707-16. doi: 10.1016/0092-8674(76)90134... at ~3.6 kb and ~1.1 kb (lane 3). Uncut DNA (lane 2) has a band at <3 kb, which corresponds to the supercoiled...dimers in Escherichia coli K-12. Plasmid. 1989 Mar;21(2):138-41. doi: 10.1016/0147-619x(89)90057-7. PMID: ...Plasmids and Chromosomes. Microbiol Spectr. 2014 Oct;2(5). doi: 10.1128/microbiolspec.PLAS-0025-2014. PMID...Behavior of Plasmid DNA. Microbiol Spectr. 2015 Apr;3(2):10.1128/microbiolspec.PLAS-0036-2014. doi: 10.1128...at lower copy numbers within bacterial cells, and bacterial cells with multimers grow more slowly compared...
  27. Flow Cytometry Readouts: Yes, No, and Everything in Between

    Type
    Blog Post
    Published
    Aug. 20, 2024, 1:15 p.m.
    ...low expression, and everything in between (Figure 2). These smears tend to occur when you are looking ...on your experiment. You can see from Figure 2 that determining where to place your gate based on the dot... dot plot would be complicated.  Figure 2: (A) a smeary dot plot showing a range of antibody readouts...plot in Figure 4 compared to the dot plot in Figure 2. Quantification using MFI makes it easier to identify...percentage of total live cells are GFP+. In this plot, with adjusted voltage, cells that did not receive ...would serve you well. Percentage of cells in a parent gate (all live cells for example) that are positive ...example, you have introduced a GFP protein into your cells (visualized via the FITC channel) and you are trying...
  28. CRISPR 101: Targeting RNA with Cas13a (C2c2)

    Type
    Blog Post
    Published
    Sept. 21, 2017, 2:07 p.m.
    ...question: C2c1, C2c2 and C2c3 (short for Class 2, candidate 1, 2, or 3). C2c1 and C2c3 are related to Cpf1,...characterization of diverse class 2 CRISPR-Cas systems." Molecular cell 60.3 (2015): 385-397. PubMed PMID...however cutting efficiency of Cas13a is reduced when 2 mismatches are present. The protospacer flanking sequence...PMC5127784. Find plasmids from this paper at Addgene. 2. East-Seletsky, Alexandra, et al. "Two distinct RNase...thought to activate programmed cell death or a dormant state for bacterial cells that have been infected with...bacterial cells, LwaCas13a does not display nonspecific RNA cleavage activity in eukaryotic cells. They arrived...target RNAs, although its usefulness in bacterial cells will likely be limited by the propensity of Cas13a...
  29. MXS Chaining

    Type
    Blog Post
    Published
    Feb. 7, 2017, 3:30 p.m.
    ...Tethering partner Subcellular localization 1 TagBFP 399nm/ 456nm histone 2B (H2B) Chromatin 2 Cerulean 433nm...based (chaining-based) cloning. The modules (Figure 2) are contained in individual plasmids and are each...between various cloning methods are listed in Table 2. For example,  chaining-based cloning methods require...suitable for combining endogenous sequences. Table 2: High Throughput Cloning Strategies Method Technology...PMID: 20205762. PubMed Central PMCID: PMC2822740. 2. Engler C, Kandzia R, Marillonnet S. A one pot, one...protein localization, as well as cellular processes like gene expression and cell migration (Sladitschek and... MXS-chaining were used to label subcellular structures in live cells. Four individual expression constructs...
  30. AAV Titers: Where Do They Come From And What Do They Mean?

    Type
    Blog Post
    Published
    Nov. 15, 2017, 3 p.m.
    ...PubMed Central PMCID: PMC3640491. 2. Grimm, D., et al. "Titration of AAV-2 particles via a novel capsid ELISA...report the physical titer of a viral solution (Figure 2). Because physical titers are used for dosing purposes...mean and how they can be compared.   Figure 2: Label that comes on Addgene’s AAV aliquots. Our titer...of genomes can limit production of recombinant AAV-2." Gene therapy 6.7 (1999). PubMed PMID: 10455443. ...Characterization of a recombinant adeno-associated virus type 2 Reference Standard Material." Human gene therapy 21.10...particles that can transduce cells. Infectious titers are typically quantified by cell transduction assays. Wild-type...
  31. CRISPR Antimicrobials

    Type
    Blog Post
    Published
    May 3, 2016, 2:30 p.m.
    ...Citorik Plasmids here). In both cases, they used 1-2 CRISPR crRNAs targeting sequences found only in certain...resensitize antibiotic-resistant bacteria (Figure 2). The first phage introduced is lysogenic, integrating...machinery targeting 1) the given resistance gene and 2) a second lytic phage. Bacteria that receive this ...bacteria have previously flourished.   Figure 2: Two-phage strategies to resensitize bacteria to antibiotics...237163. Find plasmids from this paper at Addgene. 2. Bikard, David, et al. “Exploiting CRISPR-Cas nucleases...reach essentially every cell or else small pools of antibiotic resistant cells could repopulate the environment...strategies are nonspecific - they harm any bacterial cell without a resistance gene, allowing resistant bacteria...
  32. New Neuroscience Tool: The iGluSnFR3 Glutamate Sensor

    Type
    Blog Post
    Published
    April 7, 2022, 1:15 p.m.
    ...kinetics which are illustrated in figures 2 and 3.  Figure 2: Glutamate titration curves for the different...signals upon sensing glutamate using both 1-photon and 2-photon imaging.   Figure 1: 1P and 2P excitation...adapted from Aggarwal et al…, Supplementary Figure 2.   Improved trafficking and localization through... glutamate release from neurons and other brain cells in vivo. Glutamate plays a variety of roles in synaptic...sensor to the membrane and displays it on the extracellular side. In addition to the original PDGFR TMD,...promoter, FLEXed for expression in Cre-expressing cells hSynap: Human Synapsin-1 promoter. Good for neuronal...promoter, FLEXed for expression in Cre-expressing cells. hSynap-FLP: Synapsin-1 promoter, FLP-dependent ...
  33. Common Injection Routes in Mice

    Type
    Blog Post
    Published
    Jan. 22, 2025, 9:42 p.m.
    ...Location: peritoneal cavity Gauge: 25–27 Volume: < 2–3 ml Skill required: intermediate Intramuscular Intramuscular...Location: back or hind legs Gauge: 25–27 Volume: < 2–3 ml (~1 ml per site) Skill required: beginner Intradermal...Intraperitoneal Scruffing Peritoneal cavity 25–27 < 2–3 mL Intermediate Intramuscular Mechanical restrainer...Back or hind legs; between skin and muscle 25–27 < 2–3 mL (~1 mL per site) Beginner Intradermal Anesthesia...Addgene blog Mouse Modeling Part 1 Mouse Modeling Part 2 Five Popular Model Organisms Additional resources ...different substances can be injected, including cells, drugs, DNA, viral vectors, and viruses. All researchers... injections are most often used when injecting a cell suspension to create xenograft models. Restraint...
  34. 22 Hot Plasmid Technologies from 2014

    Type
    Blog Post
    Published
    Jan. 6, 2015, 5:21 p.m.
    ...Currently available from the Kim lab are 2 presynaptic and 2 postsynaptic targeting mGRASP plasmids. Additionally... Robinson et al., Dev Cell 2010 Feb 16;18(2):324-31. Cheeseman et al., J Cell Sci 2013 May 1;126(Pt ... 2µg/ml of Doxycycline for 2 hours, and imaged on the Keyence BZ-9000 fluorescence microscope 8 hours ...promotes the formation of an isopeptide bond between 2 peptide tags, SpyTag and KTag. The group demonstrated... of three sets of cloning vectors (Level 0, 1, or 2) which can be utilized in three successive assembly...1 modules can be similarly assembled into a Level 2 vector, thus forming a functional genetic circuit....circuit. Flexibility has been built into the Level 2 vectors to allow for additional iterations of Level 1 assembly...
  35. Hassle-free 96-well Format Epitope Tagging Using Cas9 Ribonucleoprotein

    Type
    Blog Post
    Published
    June 28, 2018, 3:01 p.m.
    ...purify IVT sgRNA in the lab. Figure 2: Cas9 RNP complexed with 2-part cr:tracrRNA tags genes more effectively...is then transfected into stem cells. Cells are allowed to recover for 2-5 days and then analyzed for tagging...transfect and let cells recover for 2-5 days.Note: We use the Nucleofection method for delivery of csRNP... knock-in efficiency (<2% positive by ICC for the tag) or do not see any cells positive for tag insertion...stem cells. Development 144: 635-648. PubMed PMID: 28096221. PubMed Central PMCID: PMC5312033. 2. Dewari...IVT sgRNA) approach (Dewari et al. 2018 and Figure 2). Not only is the cr:tracrRNA approach highly efficient...transfected cells, we count the number of tag-positive cells (tag ICC) as a percentage of total cells in the...
  36. Easi-CRISPR: Generating Knock-In and Conditional Mouse Models

    Type
    Blog Post
    Published
    April 5, 2018, 12:42 p.m.
    ...of conventional gene targeting is lowered to about 2-3 months. But certain models remain more difficult...included in the final ssDNA template. Figure 2: Overview of ivTRT to generate an ssDNA repair template... floxed conditional allele requires you to target 2 loxP sites to intronic regions 0.5 - 0.8 kb apart....Typically, Easi-CRISPR works best with insertions of 2 kb or less. Luckily, most of the commonly used cassettes... induction systems (ttA or rtTA) are between 1 to 2 kb in length. There are plenty of Addgene plasmid ...create the ssDNA construct as described in Figure 2.  You can also use Addgene plasmids to purify Cas9...desired mutation in mouse ES cells, select for the mutation and inject the ES cells into a mouse embryo to ...
  37. An Introduction to Adenovirus

    Type
    Blog Post
    Published
    Oct. 3, 2023, 1:15 p.m.
    ...either SARS-CoV-2, Adenovirus type 41 (AdV-41), or Adenovirus-Associated Virus type 2 (AAV2) – or some... was either 1) a physiological effect of SARS-CoV-2 toward destabilizing one’s natural immune response...response to Adenovirus (and/or to its partner, AAV) or 2) a sociological effect of the COVID-19 lockdowns causing...… Chiu, C. Y. (2023). Adeno-associated virus type 2 in US children with acute severe hepatitis. Nature... AdVs is dependent on modulation of the host cell’s cell cycle; inhibition of the innate immune system... in the producer cells where there is E1 and E3 gene complementation. In target cells that are infected...hexon), as well as other intracellularly-exposed proteins and downstream cellular events, all recruit strong...
  38. Viral Vectors 101: An Introduction to AAV

    Type
    Blog Post
    Published
    May 30, 2023, 1:15 p.m.
    ..., AAV2/8 has a type 2 ITR and a type 8 serotype. Almost all vectors contain type 2 ITRs, which comes from...terminally differentiated, non-dividing cells.   Figure 2: DNA rescue and transduction of a conventional...quantitative PCR-based method for the titration of AAV-2 vector stocks."Molecular Therapy 6.2 (2002): 272. ...Time to expression AAVs have to infect cells, hijack host cell machinery, and synthesize a second strand...that can be used to express genes of interest in cell and animal models. AAVs are non-pathogenic, do not...be specifically targeted to a number of different cell types even when systemically administered in an ...ranging from transient gene expression in a particular cell type to CRISPR genome editing, optogenetics, and...
  39. Plasmids 101: Modular Cloning Applications and Kits

    Type
    Blog Post
    Published
    May 14, 2024, 1:15 p.m.
    ... Multiple Introns.” Plant Communications, vol. 2, no. 2, Elsevier BV, Mar. 2021, p. 100135. Crossref, ...Constructs.” PLoS ONE, edited by Jean Peccoud, vol. 6, no. 2, Public Library of Science (PLoS), 18 Feb. 2011, p... vol. 5, no. 10, American Chemical Society (ACS), 2 May 2016, pp. 1059–69. Crossref, https://doi.org/10.1021...of Plant Genomes.” The Plant Genome, vol. 16, no. 2, Wiley, 9 Mar. 2023. Crossref, https://doi.org/10.1002...Crossref, https://doi.org/10.1186/s12870-020-02388-2. Stuttmann, Johannes, et al. “Highly Efficient Multiplex...Crossref, https://doi.org/10.1038/s41598-019-46171-2. Resources on Addgene.org Modular Cloning (MoClo...can be used in bacterial and cell-free expression systems, mammalian cells, yeast, flies, and even plants...
  40. CRISPR-based Genome Editing Systems For Editing in E. coli

    Type
    Blog Post
    Published
    April 13, 2021, 1:15 p.m.
    ...place. Then plasmids are cured from the cell. Steps 1-1 and 1-2 can be done simultaneously. Image from ...1) replaced the promoter of gRNA-pMB1 with PrhaB, 2) changed the replicon of pCas into a non-temperature-sensitive... pEcCas/pEcgRNA system in 4 E. coli K-12 strains, 2 E. coli B strains, 1 E. coli W strain, and 1 Tatumella...MUCICAT better, it is faster. Using MUCICAT only needs 2 newly constructed plasmids (pDonor and pQCascade) ...rounds of transformation in 30 days. Figure 2: (A) MUCICAT plasmids for multicopy integration. (...construct and then introduce both plasmids into the cell. The edit in the chromosome can now take place. .... After editing, pTargetF can be cured from the cell by inducing expression of the sgRNA that targets ...
  41. Rett Syndrome: A History of Research and Therapeutic Outlooks

    Type
    Blog Post
    Published
    Nov. 19, 2020, 2:15 p.m.
    ...//doi.org/10.1002/1096-8628(200022)97:2<147::aid-ajmg6>3.0.co;2-o Baker SA, Chen L, Wilkins AD, Yu P, ...Caused by a mutation in the methyl-CpG binding protein 2 (MECP2) gene, Rett Syndrome is a rare, progressive...X-linked MECP2, encoding methyl-CpG-binding protein 2. Nat Genet 23:185–188 . https://doi.org/10.1038/13810... (2000) Rett syndrome: Methyl-CpG-binding protein 2 mutations and phenotype-genotype correlations. Am ...Syndrome and Related Disorders. Cell 152:984–996 . https://doi.org/10.1016/j.cell.2013.01.038 Guy J, Gan J, ...Programmable RNA Editing. Cell Reports 32:107878 . https://doi.org/10.1016/j.celrep.2020.107878 Sinnett SE...deliver the precise amount of protein to each brain cell to restore physiological levels. Much research is...
  42. Viral Vectors 101: AAV Variables That Matter

    Type
    Blog Post
    Published
    June 1, 2023, 1:15 p.m.
    ...testing your AAV.  Figure 2: Comparison of AAV serotypes 1, 2, 5, 6, 8, and 9 in two different ...your experimental conditions and measurements; (2) the cells you’re targeting; (3) how much expression is... Tropism and Axonal Transport of AAV Serotypes 1, 2, 5, 6, 8 and 9 in the Mouse Brain. PLOS ONE, 8(9),... Comparison of four promoters. Gene Therapy, 28(1–2), 56–74. https://doi.org/10.1038/s41434-020-0169-1...analyses of adeno-associated viral vector serotypes 1, 2, 5, 8 and 9 in marmoset, mouse and macaque cerebral... where many different cell types, or even different phenotypes of the same cell type, are intermingled...postsynaptic cells when used at very high titers (Zingg et al., 2017), which can lead to cells in far away...
  43. Plasmids 101: FLEx Vectors

    Type
    Blog Post
    Published
    April 28, 2016, 2:30 p.m.
    ... recombination at the cellular level in the mouse. 2003 PubMed PMID: 12665802. 2. Branda, CS and Dymecki...2008. A FLEX switch targets Channelrhodopsin-2 to multiple cell types for imaging and long-range circuit ...conditional knock-in cassette. As shown in Figure 2, the cassette should contain a reporter DNA sequence...a targeted neuronal population.    Figure 2 (modified from Schnutgen et al. Nat Biotech 2003):...delivered using AAV injection, the majority of the cells surrounding the injection site will become infected... ensure that the reporter remains silent until a cell or tissue-specific Cre is provided. Since the FLEx...used to study the physiology or behavior of certain cell populations.  Acknowledgement:Through a partnership...
  44. Using AAV for Neuronal Tracing

    Type
    Blog Post
    Published
    Aug. 9, 2018, 1:04 p.m.
    ...for retrograde transport has been found for AAV1, -2, -5, -7, -8 (Taymans et al., 2007), AAV1 (Hollis et... tropism and axonal transport of AAV serotypes 1, 2, 5, 6, 8 and 9 in the mouse brain. PLoS One 8:e76310...reveal novel hippocampal CA2 circuits. Nat Neurosci 17(2), 269–279. PubMed PMID: 24336151. PubMed Central PMCID... Mechanisms of Motility and Regulation. Neuron 84(2), 292–309. PubMed PMID: 25374356. PubMed Central PMCID...transduction efficiency of recombinant AAV serotypes 1, 2, 5 and 8 in the rat nigrostriatal system. J Neurochem...analysis of adeno-associated viral vector serotypes 1, 2, 5, 7 and 8 in mouse brain. Hum Gene Ther 18, 195–...retrograde access to projection neurons. Neuron 92(2), 372–382. PubMed PMID: 27720486. PubMed Central PMCID...
  45. Tips for Getting a Faculty Position

    Type
    Blog Post
    Published
    July 20, 2023, 1:15 p.m.
    ... this problem? (2-3 sentences) What will be the focus of your first grant? (1-2 sentences) ...of scientific success is publications and grants. 2. Write succinct and easy to understand documents A...consideration. 3. Present an easy to follow seminar See item 2. Attendees will include grad students (that are solicited...people would agree is important to understand. (1-2 sentences). For example: Distinguishing correctly ...patterning of cells and tissues is fundamental to development. I'm interested in how cells find their way...competitive CV You don't necessarily need a Nature/Cell/Science paper. You do need multiple first/corresponding... optimization of fluorescent proteins,  and live cell imaging approaches. Erik is also an avid long distance...
  46. Hot Plasmids and Viral Preps - January 2021

    Type
    Blog Post
    Published
    Jan. 5, 2021, 2:15 p.m.
    ... Opto-Cre-Vvd is fast and can cut in as little as 2 hours.  Sheets, MB, et al., ACS Synth Biol. 2020....they investigated three Casɸ orthologs, Casɸ-1, Casɸ-2, and Casɸ-3. This system is notable for several reasons...a minimal PAM requirement. For instance, for Casɸ-2 the PAM sequence is 5’-TBN-3’ (where B is G, T, or...deposited by Leopold Parts. This library delivers 2 randomly paired guides per construct and allows a ...fluorescence-activated cell sorting (FACS) helps researchers sift through thousands of cells to identify cells exhibiting...target single cells. Now, Francois St-Pierre’s lab developed a new form of FACS-based cell screening, Single-cell...individual cells with unique spatiotemporal phenotypes from large heterogeneous cultures.  HeLa cells expressed...
  47. Controlling for Off-target Effects with a New Genome-wide CRISPR Screen Design

    Type
    Blog Post
    Published
    Sept. 13, 2018, 1:55 p.m.
    ...guide expression and dsDNA breaks. Figure 2: Non-targeting vs. safe-targeting guides. The genome-wide...target all protein-coding genes present in the genome; 2) non-targeting guides (red), which target no sequence...guides that had zero mismatch off-targets. Guides with 2-bp mismatch off-targets were only toxic if they had...tolerated than mismatches more distal to the PAM, and 2) guides with high GC content have greater off-target...PMID: 28474669. Pubmed Central PMCID: PMC5424143. 2. Tsai, Shengdar Q., et al. "GUIDE-seq enables genome-wide...delivered as a pooled library via a lentiviral vector to cell lines that either stably expressed Cas9 or that ...almost all genes involved in the production of a cell surface glycan that’s required for ricin uptake....
  48. 15 Hot Plasmids from 2017

    Type
    Blog Post
    Published
    Jan. 9, 2018, 3:02 p.m.
    ...NGG)  Editing window ~2 nt  85175  pBK-EE-BE3  SpCas9 (NGG)  Editing window ~2 nt  85176  pBK-YE2-...quantum yield of 0.54) and mScarlet-H with M164H (2-fold improvement in photostability compared to mScarlet...SpCas9 base editors with editing windows as small as 1-2 nucleotides! To reduce off-target effects associated...pBK-YE2-BE3  SpCas9 (NGG)  Editing window ~2 nt  85177  pBK-YEE-BE3  SpCas9 (NGG)  Lower on-target activity...activity than BE3; editing window ~1-2 nt  87438  pET42b-HF-BE3  HF-Cas9 (NGG)  Very low off-target activity...Ladders Are Awesome Tools: They are comprised of 2 plasmids, pPSU1 and pPSU2, that can be amplified affordably...libraries The Gross Lab at UCSF recently deposited 2 Bacillus subtilis libraries with Addgene – the B. ...
  49. Viral Vectors 101: Integrase-Deficient Lentiviral Vectors

    Type
    Blog Post
    Published
    May 13, 2025, 1:15 p.m.
    ...or non-homologous end joining (see Figure 2).  Figure 2: Schematic representation of integration...developing T-cell acute lymphoblastic leukemia due to insertional mutagenesis (Howe et al., 2008). 2. Transient...vectors: progress and applications. Gene Therapy, 17(2), 150–157. https://doi.org/10.1038/gt.2009.135. PubMed...efficiently during infection. Journal of Virology, 70(2), 721–728. https://doi.org/10.1128/JVI.70.2.721-728.1996...purposes, like creating stable cell lines, delivering CRISPR/Cas9 to cells for genome editing, and introducing... chromosome of the cell. This integrated viral genome is then part of the cellular DNA… forever!  This...viral entry into the host cell.  Transfecting these three plasmids into cells enables the production of...
  50. Viral Vectors 101: What is a Virus (and a Viral Vector)?

    Type
    Blog Post
    Published
    Aug. 18, 2023, 4:15 p.m.
    ...developed around how they replicate (Figure 2). Figure 2: Baltimore replication classes. Image credit...safer viral vectors that can be used in BSL-1 or BSL-2 labs. Viral vectors are viruses that have been genetically...hijacking the machinery of the cells they infect. Once they enter a cell, they treat their viral genome...genome as a “payload” that is delivered to the cell. The cell then uses its own machinery to replicate the...replication process whereby one cell copies itself and “splits” into two cells. Viral vectors Viruses are ...virus. From one, come many After a virion infects a cell, the single particle creates many copies of itself...millions of new copies, which are released from the cell like baby spiders from an egg sac. (Okay, some enveloped...
Showing: 51 - 100 of 478 results