We narrowed to 522 results for: des.2
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TypeBlog PostPublishedSept. 10, 2020, 11:45 a.m....different destination vectors depending on the total number of gRNAs you wish to clone, from 2-7. For example... plasmids allow expression of 2-5 gRNAs in zebrafish. Custom destination vectors are used depending upon...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...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...and a subsequent curing protocol that requires only 2-3 hours incubation. Kondo Lab multiplexed base editing...
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Cpf1: A New Tool for CRISPR Genome Editing
TypeBlog PostPublishedOct. 14, 2015, 2:30 p.m....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...Cpf1 is a single RNA-guided endonuclease of a class 2 CRISPR-Cas system." Cell (2015). PubMed PMID: 26422227... Find plasmids from this publication at Addgene. 2. Zetsche, Bernd, et al. "Multiplex Gene Editing by... crRNAs for Cpf1-mediated cleavage are 42-44 nucleotides in length, about the same size as Cas9’s, but... -
Important Considerations When Using AAVs
TypeBlog PostPublishedJune 13, 2017, 2:30 p.m....Manitoba due to their Biosafety Level-2 or 2+. Please Note: Despite the fact that AAVs themselves are not...long and stable expression (up to 9 months in mice [2]). Low Immune Response: Compared to other viral vectors... location. Location (1): What tissue? Location (2): Where in the tissue/which cell type? Location (3...may be sufficient to overcome the transport issues. 2. Failure to plan (for storage) Is planning to fail...Find Ready-to-Use Retrograde AAV Preps at Addgene 2) Comparison of genetically engineered receptors (i.e...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 (... -
Starter Guide to induced Pluripotent Stem Cells (iPSCs) Part 2: Reprogramming and Transdifferentiation
TypeBlog PostPublishedNov. 6, 2018, 1:12 p.m....revert back to a pluripotent stage (iPSC formation) [2, 3]. The iPSCs then proliferate and redifferentiate... more common delivery methods include retrovirus [2], lentivirus [4], adenovirus [5], Sendai virus [6]...2006. 441(7097): p. 1061-7. PubMed PMID: 16810240. 2. Takahashi, K., et al., Induction of pluripotent stem... Pluripotent Stem Cells. Cell Stem Cell, 2015. 17(2): p. 178-94. PubMed PMID: 26189426. 15. Si-Tayeb, ...induced pluripotent stem cells. Stem Cell Rev, 2015. 11(2): p. 242-53. PubMed PMID: 25578634. PubMed Central... to regeneration. Nat Rev Mol Cell Biol, 2011. 12(2): p. 79-89. PubMed PMID: 21252997. 37. Merrell, A.... and B.Z. Stanger, Adult cell plasticity in vivo: de-differentiation and transdifferentiation are back... -
SciComm with the Experts at Science in the News Part 2
TypeBlog PostPublishedApril 27, 2017, 2:30 p.m....and Amy tell us a little about themselves. Chapter 2: What is Science in the News (SITN)? - SITN is a graduate... discusses some of the programs SITN runs and describes some of the more popular topics from the Science... fields as well as students from the ed school, design school, and Kennedy school to discuss the impacts...impacts of science in a social context. Episodes are driven by narrative and story telling. Chapter 5: The...The SITN Blog - Vini and Amy describe how the SITN blog is a source of scientific information for the ...underwater? Chapter 8: Work-Life Balance - Vini describes how she balances working in the lab and working... -
The Materials Science of Optogenetics Experiments
TypeBlog PostPublishedSept. 17, 2015, 2:30 p.m....and materials required for each [1, 2]. This protocol [3] provides, in exquisite detail, the various steps...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... -
Plasmids 101: Modular Cloning
TypeBlog PostPublishedMarch 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...cloning, or MoClo, is a systematic cloning strategy designed by synthetic biologists to perform large scale...specifically refers to the organizational schema described above, and not any particular cloning technique...example of an individual part, this category also includes promoters, UTRs, terminators, etc. Once selected... -
Five Popular Model Organisms, Part 2
TypeBlog PostPublishedSept. 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 ...pathological developments (Vieira et al., 2019) Besides their ability to regenerate, the axolotl has several...scientific history, highly characterized genome, and widespread utilization, Arabidopsis has made significant...Arabidopsis genome project marked the beginning of widespread Arabidopsis genetics research development. Arabidopsis...allows for easy cloning of constructs specifically designed for use in Arabidopsis. There are also important... -
Fluorescent Proteins 101: Photoactivatable Fluorescent Proteins
TypeBlog PostPublishedApril 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...tetroxide). These conditions destroy most PA-FPs, but, in 2015, the Looger Lab designed 2 variants of EosFP that... 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... above background. The majority of PA-FPs come in 2 flavours- monomeric and tetrameric. Tetrameric PA-... -
Viral Vectors 101: The Retroviral Lifecycle
TypeBlog PostPublishedJuly 27, 2023, 1:15 p.m....pseudotransduction” — to describe the direct protein transfer of RT, which would actually occur in step 2 during uncoating...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...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...Biology (gDNA → mRNA → protein): their roadmap includes RNA → DNA (Cooper & Temin, 1974), as one of its... -
Finding nucleic acids with SHERLOCK and DETECTR
TypeBlog PostPublishedApril 16, 2020, 1 p.m.... 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... and Functional Characterization of Diverse Class 2 CRISPR-Cas Systems. Molecular Cell 60:385–397 . https...Cpf1 Is a Single RNA-Guided Endonuclease of a Class 2 CRISPR-Cas System. Cell 163:759–771 . https://doi.... -
3 Tips to Improve HDR Efficiency for CRISPR Editing in Human Cells
TypeBlog PostPublishedSept. 5, 2017, 1:58 p.m....improving editing accuracy by preventing re-editing and (2) optimizing “cut-to-mutation distance”. Furthermore...also takes into account that HDR is rare, usually 2-5% of the edited cells in our hands, these combined...screen a few hundred clones to find the right one Step 2 – Edit the cells a second time using a repair template...Additional CRISPR Resources on Addgene's CRISPR Guide Page 2. Optimizing "cut-to-mutation distance" Even though... wisely (and let them cut close). Figure 2: Relationship between cut site to mutation distance...PMID: 23287718. PubMed Central PMCID: PMC3795411. 2. Mali, Prashant, et al. "RNA-guided human genome engineering...overall HDR rates, we have shown recently that desired genome-editing events by HDR can be generated more... -
Multiplex Genome Editing with CRISPR-Cpf1
TypeBlog PostPublishedMay 9, 2017, 2:12 p.m.... needing to work with a transfectable cell line. 2) They require larger expression vectors which are ...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...Cpf1 Is a Single RNA-Guided Endonuclease of a Class 2 CRISPR-Cas System. Cell,163(3), 759-771. PubMed PMID...editing! A recent paper from Feng Zhang's lab describes how to use Cpf1 for multiplex genome editing. ...sequence NGG TTTV PAM site preserved? Usually Destroyed Yes, Cpf1 cleaves 5' of the protospacer Multiplexing... -
CRISPRainbow and Genome Visualization
TypeBlog PostPublishedFeb. 28, 2017, 3:30 p.m....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... Find plasmids from this publication at Addgene. 2. Ma, Hanhui, et al. “Multicolor CRISPR labeling of...ortholog requires a different PAM sequence, a gRNA designed for one dCas9 should be specific to that ortholog...boxB Magenta boxB-MS2 White boxB-MS2-PP7 Despite the success of Ma et al.’s approach, fluorescently... -
Sleeping Beauty Awakens for Genome Engineering
TypeBlog PostPublishedJune 30, 2015, 2 p.m....which has been designed to perform gene transfer in vertebrates. The system is comprised of 2 components:... gene (red) for expressing the transposase enzyme.2.) The transposase enzyme is expressed (red stars) ...enzyme required for catalysis of transposition; and 2) a transposon containing the gene-expression cassette... 2015 Feb 4. doi: 10.1002/biot.201400821. PubMed. 2. Mates L, et al. Molecular evolution of a novel hyperactive...whose use is only likely to grow in the coming decades. References 1. Kowarz E, et al. Optimized Sleeping... -
Genome-wide Screening Using CRISPR
TypeBlog PostPublishedAug. 18, 2015, 2:30 p.m.... (see Fig. 2). Individual gRNAs are designed in silico using publicly available gRNA design software and...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 ... is included on the gRNA-containing plasmid, or a 2-plasmid system in which Cas9 must be delivered separately...uncontrolled cell growth, such as cancer. Figure 2: The CRISPR library must be amplified (A) to be used... be independently validated to ensure that the desired modification produces the phenotype you screened...in the first place. With the proper experimental design and validation practices, CRISPR libraries can ... -
Multiplexed Capture of Promoter-enhancer 3D Chromatin Structures Using CRISPR
TypeBlog PostPublishedJuly 2, 2020, 12:40 p.m....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...cell line expressing 1) FLAG-biotin-tagged dCas9, 2) BirA, and 3) one or more gRNAs Two separate lentiviruses...delivering 1) a BioTAP-tagged dCas9 and an eGFP tag, and 2) gRNAs Number of loci targeted One Many Sample...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...Variant for Your Next Experiment Learn More About Designing gRNAs Against Your Favorite CREs Here Additional... -
Minigenomes - a Safe Way to Study Dangerous Viruses Like the Ebola Virus
TypeBlog PostPublishedMarch 17, 2016, 2:30 p.m....study aspects of the EBOV replication cycle under BSL-2 conditions (4). What is a minigenome? The EBOV ...transcription by the EBOV polymerase (reviewed in 2, 5). The minigenome is capable of being replicated...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...minigenome system Minigenome systems, such as the one described here, are extremely useful research tools. In ... -
A Primer on Optogenetics: Introduction and Opsin Delivery
TypeBlog PostPublishedSept. 10, 2015, 2:30 p.m....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...analysis of microbial opsins. Nature methods. 2012;9(2):159-72. doi: 10.1038/nmeth.1808. PMID: 22179551; ... -
Viral Vectors 101: Optogenetic Tools
TypeBlog PostPublishedJune 27, 2023, 1:15 p.m....al. described the first light-activated tool for controlling neuronal activity, channelrhodopsin-2 (ChR2...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 ...intracellular signaling pathways. Trends in Biotechnology, 33(2), 92–100. https://doi.org/10.1016/j.tibtech.2014.11.007...