... Gen AdVs were designed to have increased cloning capacity, decreased  potential for the generation of...E4 are deleted in 2nd generation AdVs, thereby increasing cloning capacity to ~12 Kb. The ever popular ...generated high interest for gene therapy due their increased cloning capacity (up to 36 kb!), long-term transgene...AdEasyTM system is the most popular method for creating adenoviral vector constructs. It consists of 2...can be repeated multiple times (2-4 rounds) at increasing scale over the course of 1-2 weeks. Each round...of amplification should result in a 10-100-fold increase in virus. Purification (2 days) - Purification...

... prior to their transduction has been shown to increase AAV transduction efficiency by approximately 15...efficiency depends on viral titer Both of these can be increased by concentrating a viral stock. Different titering... virus-cell contact A variety of reagents can increase transduction efficiency. These reagents typically...reagent that is commonly used and has been shown to increase transduction efficiency by 10-fold (Davis et al...hematopoietic or primary cells), and has been shown to increase transduction efficiency by 1.5-fold (Stockschläder...12705861. 3. Chen, Sifeng, et al. "Freeze-thaw increases adeno-associated virus transduction of cells."... R. Morgan, and Martin L. Yarmush. "Polybrene increases retrovirus gene transfer efficiency by enhancing...

...different compositions of the Cascade complex. Created with BioRender.com.   The Cascade complex Cascade...Figure 2: Cascade complex from CRISPR type I-E. Created with BioRender.com. Thanks to this complex,...Tomoji Mashimo lab and the Tilmann Weber lab — to increase efficiency of these systems, though consistent...General overview of the Cascade-Cas3 mechanism. Created with BioRender.com.   The reeling mechanism...unwinding of dsDNA occur simultaneously, which creates a loop in the target strand that is cut occasionally...repair without the section between the two gRNAs, creating a deletion. However, there is the chance of a .... Future targets Cas3 has the potential to be incredibly useful in therapeutics. Imagine deleting a problematic...

...Factors to consider when creating a pooled library amplification protocol. Created with BioRender.com. ...Re-transformation of the SPLINTR Libraries (PDF, 401 KB) Screening Zhang Lab - Multiplexed Overexpression of Regulatory...et al. Nat Protoc. 2017 with modifications Screening pCMV-Rep78/68 Scanning Saturation Mutagenesis...Amplification and Sequencing Protocol (DOCX, 32 KB) Screening Rinehart Lab Iterative Synthetically Phosphorylated...-Cas9 knockout and transcriptional activation screening, a protocol paper by the Zhang lab, and the Broad...More resources on the Addgene blog Genome-Wide Screening Using CRISPR Preparing Pooled Libraries NGS Quality...

...expression? Are you trying to create a single point mutation? Do you want to create a fusion with a reporter...include a homology directed repair (HDR) template to create knock-ins, point mutations, or to add a tag, you...vivo. A common choice for conducting genome-wide screens using CRISPR. AAV transduction Only compatible...Transient expression of CRISPR components, expression decreases as RNA is degraded within the cell. Can be used...Transient expression of CRISPR components, expression decreases as gRNA and Cas9 protein are degraded within the...validated tools.  Special thanks to Joel McDade for creating the Expression Systems table. Marcy Patrick contributed...

...and found that 50 nt spacers increase editing efficiency but also increase off-target editing within the...1090), which decreases the REPAIRv1 construct size from 4,473 bp to 4,152 bp without decreasing editing efficiency..., which deaminate adenosine to inosine in RNA, creating a functional A->G change. They fused ADAR deaminase...to dPspCas13b, but observed low RNA editing. To increase A->G editing, they employed hyperactive ADAR constructs... they hoped to destabilize ADAR-RNA binding to decrease off-targets. Of the tested constructs, ADAR2DD...

...generation oil are moved through small channels to create a water-in-oil emulsion containing approximately...the number of positive droplets as the dilutions increase. The ddPCR software uses the ratio of positive...parameters, here are a few things you can try: Increase the number of cycles. After additional rounds ...amplification, your fluorescence amplitude will increase, leading to greater separation of your positive...droplets. No more than 50 cycles is recommended. Decrease your ramp rate. A rate of 2C/s is recommended ... the droplets, but you can go as low as 1C/s. Increasing the elongation time to 2 minutes and the denaturation...denaturation time to 1 minute has been shown to increase droplet separation (Witte et al., 2016). This is...

...CRISPR screen to disrupt these enhancers. The third and final step is to conduct our CRISPR screen. We start... the marvel of DNA compaction, an enhancer can increase the expression of a gene that is millions of base...stem cells, and conclude with a targeted CRISPR screen that can disrupt these enhancers. A real-world ...that have NANOG binding sites 2. Design a CRISPR screen to target and disrupt the NANOG enhancers 3. CRISPR...you’re interested in designing your own CRISPR screens for enhancers, check out the Appendix. Conclusion...precision medicine. We can apply this knowledge to create targeted disease therapies with minimal side-effects...

...Website: http://protocols.io/ Protocols.io is the creation of ZappyLabs. Currently in beta testing, the software...courses, as well as a space for research labs to create their own lab or group websites. OWW is managed... cells. If you’re familiar with the process of creating and editing Wikipedia pages, OWW will be relatively...The site allows you to comment on protocols and create lists of your favorite protocols for future reference...of the early protocol sharing websites. It was created in 1999 and allows scientists to contribute protocols...web-based lab management tool that allows labs to create accounts in which their members can share protcols...your lab’s needs. At Addgene, we’ll continue to create new molecular biology educational resources, such...

...Fluorescent Protein (GFP) has likely existed in creatures such as jellyfish for millions of years; however...physiological processes. Re-engineering GFP to increase its range of color and application Almost as.... Tsien described an S65T point mutation that increased the fluorescence intensity and photostability ...derivatives Mutation Known Function S65T Increased fluorescence, photostability, and a shift of the... the major excitation peak to 488 nm F64L Increased folding efficiency at 37C Y66W Causes the chromophore...Blue-shifts the wavelength (blue derivatives) Y145F Increases quantum yield for BFP Y145A and H148D Stabilizes...to identify particular cell populations in drug screens, to visualize micrometastases in nude mice in cancer...

...USA have used AAV1 and AAV2 serotypes in order to create an atlas of the mouse brain. This atlas enables...antibody recognition of epitope tags. Thus they have created antigenic protein tags called “spaghetti monster... FPs fused to multiple epitope tags. Indeed, to create the smFPs Looger’s team strategically inserted ...antibody-based amplification of their signals is weak and increases background fluorescence. Furthermore, many of ...instance, smFPs have been used to visualize “thorny excrescence” (TE) spines in the Hippocampal CA3 pyramidal...sites and primary antibody-based detection, smFPs create much brighter signals for weakly expressed proteins...: Making the journey from axon to nucleus AAVs CREATEd for gene delivery to the CNS and PNS Resources...

...significant knowledge gap in your field or even creating a new field. A knowledge gap is an impediment ...of experiments or a laundry list of molecules to screen has unclear utility. You cannot predict what will... have no hook. A battery of new assays for your screen result may or may not actually help. Ultimately...distinguish mechanistic questions from open ended screens and data collection. Organize your research vision...want to know the answer to your research problem. Creating a coherent unified story and model can help make...Consider going beyond the whiteboard. You may wish to create a sculpture or print a 3D model to better illustrate... His interests include the quality control of secretory proteins in the Endoplasmic Reticulum, optimization...

...level of antigen in the sample. This figure was created with BioRender.com  Direct ELISAs A direct ... bind non-specifically to assay components and increase background staining. Direct ELISAs also lack the... antibody. Incorporating a secondary antibody increases the sensitivity of the assay, since multiple secondary... both primary and secondary incubation steps, increasing the workload and time commitment for users. This...antibodies for the capture and detection steps, which increases the specificity of the assay. The assay is also...antibody availability Longer protocolLess specificityIncreased chance of cross-reactivity Sandwich ... High specificityHigh sensitivity Longer protocolIncreased chance of cross-reactivityChallenging to develop...

...they function in nature can inform us on how to create better recombinant vectors. In this blog post, ...provide tips on how we can harness those features to create broad host range recombinant vectors.  A plasmid... host range in plasmids? Not all plasmids were created equally. Only a handful of plasmids have been identified..., from broad host range plasmids can be used to create recombinant vectors that can replicate in different...vinelandii, Brevibacterium methylicum, Caulobacter crescentus, Desulfovibrio vulgaris, Erwinia carotovora, ..., Bordetella spp., Brucella spp., Caulobacter crescentus, Escherichia coli, Gluconacetobacter xylinus,...recombinant vectors can be modified further to increase the range of hosts in which proteins can be expressed...

...Villarreal. By the late 1980s, scientists even created a codon adaptation index (CAI) that is based on... (Sharp and Li, 1987). In 2000 the Ikemura lab created the Codon Usage Tabulated from GenBank database...interest based on an organisms codon usage bias to increase translational efficiency and thus protein expression...across an entire polypeptide. Many researchers have created codon-optimization algorithms/resources (Athey ...study, codon optimization resulted in a 6-9 fold increase in expression of these channels providing scientists...to codon optimize? Although codon optimization increases protein production in certain systems, synonymous...optimization may not always be the optimal strategy for increasing protein production. If you are trying to express...

...s lab performed a series of positive selection screens in bacteria to identify mutants of S. pyogenes ...sequences (Kleinstiver et al. 2015). From these screens, they identified four novel SpCas9 variants with...some cleavage with an NGA PAM. This variant may increase the specificity of genome modifications at DNA...allows for expanded PAM recognition as well as increased specificity and lower off-target activity (Hu ...proteins has and will continue to dramatically increase the number of CRISPR applications. The first non-Cas9...formation of “sticky ends” rather than the blunt ends created by Cas9. Cas12a  displays lower off-target editing...) system fuses Cas13b to RNA deaminase ADAR2 to create a specific RNA editor. Cas13 enzymes are advantageous...

...limitations to facilities and indirect costs, and increased tariffs present an unprecedented challenge to ...to help research institutions maximize their increasingly limited resources: Preserving scientific assets...authenticated materials at a fraction of the cost of creating and verifying them independently — particularly..., and antibody production that labs may find increasingly difficult to maintain or access. These services...with industry and public and private partners to create additional pathways for critical scientific work...community has demonstrated remarkable resilience and creativity in the face of funding challenges. By strengthening...

...was Addgene's first distributed plasmid and was created in the lab of my thesis advisor, Dr. Bruce Spiegelman...requested item of 2005. shRNA - In 2006, we saw an increase in popularity of empty backbones for shRNA expression...requested. Ubiquitin - One particular gene we saw increased interest in from 2008 to 2009 was ubiquitin. The...popular with scientists, but 2012 was marked by increased deposits (and requests) of biosensors, optogenetics...and for so many different purposes that we had to create a CRISPR page to keep up with all the new plasmids...of plasmid sharing? Check out this infographic created by our own Addgenie, Laura Veckerelli. Click on...

...also helps confirm that lanes are loaded evenly. Created with BioRender.com. Loading controls are even...normalized values for the two conditions are equal. Created with BioRender.com. This kind of normalization...must be addressed with separate controls (green). Created with BioRender.com. Researchers often rely ... of the assay is between the two dotted lines. Created with BioRender.com. To see why this S-shaped...protein abundance versus band intensity (right). Created with BioRender.com. On this gel, the protein...loading control that can be used for normalization. Created with BioRender.com. Assumption #1: The loading...protein approach. By eye, it’s difficult to see an increasing concentration of β-actin in panel A. Indeed, ...

...Harvard. There’s an astounding number of ways to create chromosomal mutations in bacteria, so many that...of surrounding genes. However, there are ways to create scarless mutations, ones that don’t leave any undesired..., CRISPR-Cas9 technology has also aided in the creation of scarless mutations, both in stand-alone systems...systems (Jiang et al., 2013), and those which increase the efficiency of Lambda red (Pyne et al., 2015;... recombineering (Khetrapal et al., 2015). They created vectors for Lambda Red that contained one of eight...aeruginosa. These toxins were a mix of Type VI secreted effector toxins, toxin-antitoxin type toxins, ...Enterobacter cloacae, and Serratia marcescens and have created dozens of deletions as well as insertions with ...

...therapeutic interventions for cancer. This screening platform is an incredible boost to the cancer research community...Barcoding (HiTMMoB) technique (Tsang et al., 2016), creating a collection of plasmids each carrying a single...mutations The researchers used the collection to screen individual perturbations in vitro using Ba/F3 and...~22% of the mutations, however, significantly increased cell viability, and these “activators” may be ...annotation of rare gene aberration drivers of pancreatic cancer." Nature communications 7 (2016): 10500...

... in yeast Base editing CRISPRi in Caulobacter crescentus Multiplexed gRNA for human pluripotent stem cells...editing. Using several rapid and cost-effective screening methods, David Liu’s lab identified and validated... base editor plasmids CRISPRi in Caulobacter crescentus Figure 1: Serial dilutions of CRISPRi in...adapted from Guzzo et al., 2020. Caulobacter crescentus is a popular model organism for studying the ...ctrA sgRNA and saw that the levels of ctrA mRNA decreased after 20 minutes in xylose (which controls expression...methylcytosine oxidation to DNA repair, which increases activation of methylation-silenced genes. Read...

...membrane depolarization increases the BRET signal whereas hyperpolarization decreases the signal. The authors...technologies that can accelerate your research. The creation of NanoLuc® Luciferase from a rather dull 19kDa... by NanoLuc® luciferase (NLuc) and set about to create an in vivo imaging reporter by linking two CyOFP1...-Lanterns with NLuc and called their improved creations Enhanced Nano-Lanterns. These great imaging tools...the two fluorescent proteins together thereby increasing their FRET signal. FRET is a non-radiative transfer...overlap with this optogenetic tool, they needed to create a calcium sensor with the following characteristics...

...International Mentorship Program (IMP) USA-Europe was created. IMP as an idea was conceived and developed by ...the specific technical and logistic support to increase the chances of success, but also nurture a supportive...country of origin with an international mentor creates a closer and more approachable relationship for...at IMP In these sessions, mentors helped mentees create “Career Development Plans” which provided paths...developmental needs and resources needed to pursue them, increased their network of contacts important for their ...Conference highlights included remarks by the Spanish Secretary of Research, Development, and Innovation, D. Carmen... as they witness their student’s progress and increases in self confidence. These improvements, combined...

... biosensor creation, and custom FRET biosensors can be created using the cpFRET kit created by Olivier...Robert Campbell’s lab display calcium-dependent increases in fluorescence of up to 11,000-fold. FRET biosensors...biosensors. Blue flame “cameleon” calcium sensors created by Roger Tsien’s lab contain two fluorescent proteins...calcium binds, it triggers CaM/M13 interaction that increases FRET transfer between the fluorescent proteins...

...experiments but we can definitely give you credit for it and increase your impact! Download ReFigure extension...along with the article metadata, legend and user created notes on a “Pinterest for scientists”? ReFigure...Linkedin and ResearchGate profile. To see how to create ReFigures in a few minutes, visit our YouTube [email protected] Please support ReFigure by creating ReFigures and answering this 2 minute survey! ...impact of teaching and doing science is rapid, concrete and open to innovation by all.  Additional Resources...

...positive selection, negative selection, and/or screening. We’re focusing on positive and negative selection...in this blog post, but don’t worry, we’ll cover screens in a future post. Positive selection: Cells that...with or without your inserted DNA) and further screening will help you determine if the plasmid backbone...arises in yeast. For example, Markus Ralser’s lab created a yeast prototrophy kit containing 23 plasmids ...bacteria to grow on sucrose. Plasmid cloning: Creativity with naturally occurring genes  At this point... scientists are finding more and more ways to creatively perform selections in plasmid cloning. Additional...

...are under a Creative Commons 3.0 license, which requires users to give appropriate credit, provide a link...about new scientific techniques and cool plasmids. Creating graphics were usually the last thing I thought..., I found some free design software that let me create graphics that better communicated the science in...reasons why this was the first program I used to create graphics for the Addgene blog. However, it has ...requested, although there’s no guarantee Biorender will create it. Additionally, you can upload your own images...

...CRISPR pooled gRNA libraries that can be used to screen for genes involved in a wide variety of cellular...processes. While these are widely requested and incredibly useful tools, they require extensive background... infect target cells, and, finally, conduct the screen. To help alleviate some of this labor for our ...optimization-scale infection and at least one screening-scale experiment achieving the gRNA representation...) says: "When you're setting up to do a genetic screen, you need to focus on building a really good model...use along with lentiviral packaging plasmids to create your own lentivirus stocks. Our research scientists...

...Natsume et al., 2016). Now, the Kanemaki lab has created a new toolkit of plasmids for the N- or C- terminal...makes it easy to tag your protein of interest to create conditional human cell lines. Lastly, the Kanemaki...sites adjacent to an NG PAM in human cells. The increased versatility of the engineered SpCas9-NG and its...enhancers, or have attempted to engineer loops to create genomic interactions that wouldn’t normally occur...develop dCas9 for synthetic looping, the Phillips-Cremins lab developed the light-activated-dynamic-looping...were able to observe loop formation as well as increased Zfp462 expression within 4 hours of blue light...

...self-assembling split GFP (GFP1-10 and GFP11) to increase fluorescence 10-fold after protease activity (... (To et al., 2016). However, the lab wanted to increase the fluorescence range to better study the spatio-temporal...β-strand of GFP, hence the name FlipGFP. FlipGFP increases fluorescence 100-fold compared to other reporters...can be applied to other fluorescent proteins to create an array of multicolor reporters that will enable...apoptosis during embryo development. GFP fluorescence increased over time and showed a clear pattern in the developing... This reporter achieves approximately 100-fold increase in fluorescence after cleavage by executioner ...

...CIB1 to regulate botulinum neurotoxin were also created. The depositors demonstrated the utility of light-mediated...these gas vesicle proteins scatter sound waves and create ultrasound contrast. At a very low volumetric density...s lab at MIT pushed the field further with the creation of the largest miRNA sensor collection reported...al., Nat Commun, 2019. PubMed PMID: 29934631. Screening immune cell lineages in vivo using the CRISPR-...tools have been used in immunology for in vitro screens of immune cell activity. However, a CRISPR-based...gene. CHIME can also be used for high throughput screens using pooled libraries. Find the CHIME plasmids...

...targeted via RNAi. Recently the Vellai lab has created an improved RNAi vector that leads to significantly...non-specific nucleotides into the dsRNA leading to increased RNAi efficiency. Find the T444T plasmid here... used yeast display-based directed evolution to create APEX2. They have now applied the same directed ...the biotin ligase from which BioID was derived, creating a pair of enzymes that overcome both the speed...BioID, which only functions optimally at 37℃. The increased efficiency of TurboID and miniTurbo makes PL a...include protein stability, small molecule binding screens, peptide arrays, and phage display selections. ...

...recording data. Increasing the voltage will shift the population to the right while decreasing the voltage...clearly distinguishable as two separate populations. Created with biorender.com. Pro tip! If your samples...smeary dot plot shows the population of interest. Created with biorender.com.   In such cases, instead...histogram plot for a yes/no flow cytometry readout. Created with biorender.com.   Using histogram plots...baseline expression of the protein of interest. Created with biorender.com. The plot above is for a...

...David Liu’s lab created the first base editor in 2016 (Komor et al., 2016) and since then has been trying...David Liu’s lab set out to evolve ABEs with an increased compatibility to Cas homologs. Evolving better...bacteriophage, which rely on the expression of gene III to create infectious particles. A plasmid-based genetic circuit...III to base editor activity and editing speed. Created with BioRender.com. Introducing ABE8e - a fast...about 7 times higher than ABE7.10. However, the increased editing speed and targeting scope of ABE8e comes...comes with a price: ABE8e showed increased off-target DNA and off-target RNA activity. To mitigate this...

...could mean needing to increase crosslinking to counteract the effects of increased sample agitation; a ...such as qPCR or next-gen sequencing. ChIP is an incredibly useful application for exploring these interactions...crosslinking, which uses formaldehyde or UV light to create strong but reversible bonds. This will keep the... necessary for most ChIP experiences, but the increased binding can mask the epitopes antibodies recognize...shorter sonication time could be an opportunity to decrease crosslinking. (Homogenization for a tissue sample...

...psychological sciences were called into question after credible attempts to replicate major findings could not...our readers into believing the results are more credible than they actually are. Throwing out plates that...preregistration Preregistration is the process of creating a time-stamped research plan in a public repository...the Center for Open Science in order to reward increased transparency and reduced bias in scientific research...Openness Promotion Guidelines; preregistration to increase clarity in study design and analysis; removing...bias with Registered Reports; and recognizing increased transparency with badges. Before coming to the...

... technology has been used to optimize protein secretion and expression in the biotech workhorse yeast ...Engineering disease resistance through gene stacking, increasing production of a protein of interest, and improving...genetic circuits with multiplexed guides, mini screening libraries, direct edit optimization, and more....can be invaluable for more complex editing and screening experiments in organisms that don’t yet have these...modify it as necessary. And remember, if you end up creating a really cool MoClo kit, we would love for you...Modular Toolkit for Generating Pichia Pastoris Secretion Libraries.” ACS Synthetic Biology, vol. 6, no.... of the GoldenBraid Modular Cloning System and Creation of a Toolkit for the Expression of Heterologous...

...assaying a secreted protein, first block the Golgi apparatus with Brefeldin A to inhibit secretion and then...through the cell membrane. Formaldehyde fixation creates cross-links between lysine residues thus preserving...flow cytometry data users will typically start by creating a dot plot of FSC versus SSC that allows them ...initially gating the lymphocytes, one could then create a dot plot of CD3 (T cell marker) versus CD19 (...cells, might then gate the B cell population and create a histogram of CD19-containing cells versus total...cells in that sample. Alternatively, they could create additional dot plots of various CD markers to further...

...may not result in any cells, or all the colonies screened might not contain the correct plasmid. There’s...and if the sequence has high GC or AT content, increase the overlapping region of the primer to 40-60 ...buffers used in the previous reactions. This will increase your chances to have a successful and ultimately...pick the big colony and you are safe! Colony screening Pick a few colonies (5-10) and grow them in a ... you've identified potential clones after the screening, sequence the plasmid. Many vectors contain sequences...can use the chromatogram to spot whether any discrepancies between your sequencing result and the expected...