... integration of a novel gene randomly into their genome, some transgenic strains are difficult to breed...expression level of the transgene. In existing strains of mice, the transgene can be maintained on a hemizygous...are many types of genetically engineered mice: transgenic mice, knockin and knockout mice, and conditional...that only one chromosome needs to contain the transgene in order to see an effect. Hemizygous mice can...breed. Some problems with transgenic mice that can impact reproduction include embryonic lethality, a short...expression level, and site of integration of the transgene. These problems can be mitigated in different ...different ways. Prior to engineering a transgenic strain, the promoter being used should be tested in cell lines...

...AAAS Science and Technology Policy Fellow at the Veterans Health Administration. “But, seriously, what even...Science and Technology Policy Fellow (STPF) at the Veterans Health Administration, I could never get one straight...variety of backgrounds with technical expertise that ranges from astronomy to bioethics to chemical engineering...happen at the national level within the executive branch or in Congress, or can also happen at the state... early career researchers who have decided to transition out of academia from graduate school or a postdoc... came to DC to do either a sabbatical year or transition away from academia as tenured professors. There...taken through your own personal lens.  For me, the Veterans Health Administration was the perfect position...

...vivo starts with transducing cells with the CRISPR library in vitro before transplanting them into mice....time. This reduces the chance of integration at random locations that could cause deleterious effects....portions of the AAV genome can integrate at double-stranded break points caused by CRISPR-Cas9 editing. The...The good news is that this integration is not random, nor is it a global occurrence, as integration sites...target cells or tissues. AAV also shows improved transduction efficiency over lentivirus in many mouse tissues...019-12449-2 Pupo, A., Fernández, A., Low, S. H., François, A., Suárez-Amarán, L., & Samulski, R. J. (2022..., U., Jabaudon, D., & Platt, R. J. (2023). Transcriptional linkage analysis with in vivo AAV-Perturb-seq...

...only have to worry about cloning your transfer plasmid. The transfer plasmids have different packaging capacities...AAV and lentivirus requires three plasmids — a transfer plasmid containing your gene of interest plus ...in mammalian cells is relatively quick. After transfection, HEK-293T cells start producing virus within...systems, it is standard to do only one passage (transfection). This differs from typical insect cell preparations...an additional couple of days, as it requires transduction of more cells, while AAV can be titrated following... baculovirus requires only two plasmids — your transfer plasmid and the baculovirus construct, called ...between insect and mammalian systems. Baculovirus transfer plasmids have a much larger packaging capacity...

...tool that responds strongly to magnetic fields (Frank Hayward et al., 2024). They deposited their plasmid...proteins. Motivated by curiosity Although a wide range of fluorescent proteins and optogenetic tools exist...when a small magnet was passed over the sample (Frank Hayward et al., 2024). The fluorescence intensity...the magnetic field is on. Image reproduced from Frank Hayward et al. 2024 under CC-BY license. They...mScarlet, and AsLOV2. After several rounds of semi-random mutagenesis and screening, the EGFP and mScarlet...the magnetic field is on. Image reproduced from Frank Hayward et al. 2024 under CC-BY license.   ...tools for biological applications across a wide range of topics. He embraces open science, self-publishing...

...separation of the two DNA strands.  Annealing- The temperature is then dropped to a range in which the forward...the primers can anneal to the single stranded DNA template strands. DNA polymerase is also stable at this...template DNA to amplify from and unique single stranded DNA primers that bind upstream (5’) and downstream... process as DNA polymerases require an existing strand of DNA to add nucleotides to.  Using these reagents...reaction:  Denaturation- To amplify DNA, the two strands of the template DNA first have to be separated....used to quantitate RNA levels using reverse transcription-qPCR (RT-qPCR). The first step of this process...requires RNA to be converted to cDNA using reverse transcription and the cDNA is subsequently quantified by qPCR...

...or Förster] resonance energy transfer). FRET occurs when energy transfer from one FP (e.g. CFP) excites...classified by the emission color (emission wavelength range) FPs are usually classified by emission color as...as outlined below (or emission wavelenght range).  By mutating GFP, the variants blue FP (BFP), cyan FP...nm Green 499 - 519 nm Yellow 524 - 538 nm Orange 559 - 572 nm Red 574 - 610 nm Far-Red 625 -... ≥ 670 nm In addition to emission wavelength range, there are other traits that need to be considered... green or red light. For example, T-Sapphire, LSSmOrange, and LSSmKate. Fluorescent Sensors: These FPs...related colors. Furthermore, most FPs  have a broad range of emission which will be detected by longer-wavelength...

...Uniform Biological Material Transfer Agreement (UBMTA) for its material transfers. The UBMTA was drafted by...organizations Assurance that recipient may not use the material for a commercial purpose Assurance that recipient... has time for paperwork? Here’s why a Material Transfer Agreement (MTA) matters: Science thrives on collaboration...universities and institutions require them for material transfers. When Addgene entered the plasmid sharing space...receiving institution. Therefore, many technology transfer officers are familiar with the UBMTA and are happy...  material transfer agreement...

... dilution should fall within the range of the assay for a wide range of titers. We usually dilute our ...determine if your titers are within the expected range. We have also found that generating the standard...For these reasons, we are in the process of transitioning our titering method from qPCR to ddPCR. Droplet...virus. It is important to note that the dynamic range of the ddPCR is between 1 and 100,000 genome copies...per reaction. Since AAV titers tend to be in the range of 1012 to 1013 GC/mL, you must serially dilute ...million.  After making the dilutions, they are transferred to a new plate containing the mastermix which...generator, you will have to be careful about transferring your droplets from the droplet generator to ...

...dCas9 has focused on transcriptional activation using a fusion to a transcriptional activator such as VP64...repression of transcription through binding a promoter region to inhibit association of transcriptional activators...locus of interest, the promoter region of the transcription factor IRF-1. Immunoprecipitation, using an ...2018). Furthermore, the Fujii Lab generated a transgenic mouse line and retroviral expression system for...Tapscott Lab identified regulators of DUX4, a transcriptional regulator that when inappropriately expressed...PMCID: PMC6001023. Fujita, Toshitsugu, et al. "Transgenic mouse lines expressing the 3x FLAG‐dC as9 protein...CRISPR-mediated modular RNA-guided regulation of transcription in eukaryotes." Cell 154.2 (2013): 442-451. ...

...false positive colonies. Transformation - the linear fragments are transformed into E. coli and plasmid...assembly of a circular plasmid in vitro, before transforming it into E. coli for propagation. However, while...using a simple two-step, 2 hr protocol prior to transformation (Figure 1). As this approach requires no special... encode homology arms to allow immediate co-transformation with linearized vector backbone. DpnI digestion...failed so far. What is most important is the transformation efficiency of the strain: when asking the cell...high fidelity DNA polymerase This will minimize random errors during PCR: we recommend Phusion or Q5. ...investigating the molecular biology of synaptic transmission and plasticity.     Javier García-Nafría is ...

... inducible translocation trap (ITT) system to analyze signal-induced nuclear translocation of proteins...functions such as epigenetic regulation and transcription by using locus-specific chromatin immunoprecipitation...biochemical analysis of genome functions such as transcription and epigenetic regulation. To elucidate molecular...Addgene realizes the One-Stop shopping for a wide range of plasmids. The merit of depositing plasmids to...considering the peer-review system of journals and grant applications, for example. However, at the same ...living for Japanese, which is not trivial, and the grant situation is currently much better than that in ...tough competition for academic positions and poor grant situation. So, young researchers need to publish...

... of fluorescence: For applications that involve ranges of pH, and significant lengths of time, the stability...receptor conformation and signaling activity​​ (Sridharan et al., 2014). It's also crucial to evaluate how...the background. Dyes that can pass through cell membranes can prove useful for live-cell imaging. Experimental...considerations regarding the choice of fluorescent dyes (Sridharan et al., 2014). Manufacturers will typically recommend...accurate tagging. In Fluorescence Resonance Energy Transfer (FRET) applications, the dyes need to have compatible...and emission profiles to enable effective energy transfer, which is key to observing interactions and conformational... specifically to the AT-rich regions of double-stranded DNA and exhibits a blue-fluorescent light when...

...injections can be found here [5, 6]. Opsin transgenic mice Transgenic mouse lines have also been engineered...specific brain region can result in a particular neurotransmitter release or post-synaptic current. Fortunately...available, instructions for obtaining a material transfer agreement, and list of vendors (such as the vector...at a similar spectrum as HR and also results in membrane hyperpolarization but unlike HR, this is achieved...[10]. Unfortunately, opsins are not actively transported and must passively diffuse so, depending on the...axonal tracing with fluorescent proteins in nontransgenic and cre driver mice. Current protocols in neuroscience...et al. A toolbox of Cre-dependent optogenetic transgenic mice for light-induced activation and silencing...

...protease allows a transcription factor to enter the nucleus and modulate transcription of the mCitrine ...HeLa cells were transfected with plasmids encoding FPs tagged with the plasma membrane targetin sequence...non-specific labeling. For labeling the plasma membrane, they tested different target sequences for improved...expression can vary significantly depending on transgene design and delivery. To overcome these variations...into genomic DNA with the help of the piggyBa transposase. Image from Hazelbaker et al., 2020. The lab...activating expression of TCF4 while monitoring transcript and protein levels. Plasmids for multiplexed ... new serotype PHP.V1 that exhibits efficient transduction of vesicular brain cells. Find this AAV at ...

...amplification) or reverse transcriptase (RT)-RPA, respectively. RPA is coupled with T7 transcription to convert amplified... method termed DNA Endonuclease Targeted CRISPR Trans Reporter (DETECTR) (Chen et al., 2018). Both SHERLOCK...almost anywhere as lateral flow strips are easy to transport and work rapidly, providing reliable results in...    DETECTR- DNA Endonuclease Targeted CRISPR Trans Reporter Cas12a (Cpf1) is a CRISPR Cas variant that...discovered Cas12a’s ability to cleave non-specific (trans) ssDNA and harnessed this ability to create a DNA...DNase activity of Cas12a is initiated. Surrounding trans-ssDNA, including the ssDNA-FQ reporter are subsequently...Servellita V, Singh J, Miao X, Streithorst JA, Granados A, Sotomayor-Gonzalez A, Zorn K, Gopez A, Hsu ...

...promoter of another gene, thereby driving aberrant transcription. That being said, we generally pick guides...been significant work on constructing Cas9 transcriptional activators. These constructs allow for the ...Cas9 deficient in DNA cutting activity to a transcriptional activation domain (Fig 1). Two ways to use...picking whichever guides are closest to the transcription start site (TSS). We recommend targeting the...Latency Reversal Using CRISPR/Cas9-Derived Transcriptional Activator Systems. PLoS ONE 11:e0158294 . https...Church GM (2015) Highly efficient Cas9-mediated transcriptional programming. Nat Methods 12:326–328 . https...Nishimasu H, Nureki O, Zhang F (2014) Genome-scale transcriptional activation by an engineered CRISPR-Cas9 complex...

... cell types. Specific transgene expression can be also achieved in nontransgenic animals by using cis ...delivery by increasing transgene cargo capacity, enhancing anterograde transport efficiency, and engineering...proteins that determine the AAV serotype. During transduction, the viral capsid proteins bind to the target...serotype used for a specific cell type. Find some transduction characteristics of select AAV serotypes in Table... AAV vectors are common approaches to control transgene expression by restricting expression to genetically...enhancers, multicistronic vectors, and post-translational regulatory elements. Examples of these approaches...

...enzyme or transcriptional activation, conformational changes, translation, and protein translocation. Targeting...triggers CaM/M13 interaction that increases FRET transfer between the fluorescent proteins. FRET is highly...characteristics like pH, redox state, and voltage across membranes. These sensors generally follow the same pattern...an organelle-specific targeting signal or a transmembrane domain, biosensors can be targeted to a particular...endoplasmic reticulum (ER), vacuole or cellular membranes. Examples include blue flame mitochondria-targeted...

... the CAR facilitates signal transduction and release of cytotoxic granules from the T cell. When a CAR...., 2012, Bates and Power., 2019): rapid blood clearance, which is useful for imaging applications; better...small size (Bates and Power., 2019). Their rapid clearance from blood can be a drawback for therapeutic applications... has led to their application for basic and translational research.  Basic research applications of scFvs...single molecule tracking in living cells. The HA frankenbody is an HA tag detection probe. It contains an ...to a fluorescent protein such as GFP. The HA frankenbody works just like an antibody-based probe, but ...generate since it’s genetically encoded.   Translational applications of scFvs: Just like antibodies...

...fluorescent protein (XFP) genes in a transgene. When multiple copies of the transgene cassette are introduced, stochasticity...fluorescent proteins is only possible at low copy number ranges, resulting in low fluorescent protein level. The...gene delivery is more common than conventional transgenic strategies. In such vector-based gene delivery...in the original method, we used the Tetracycline trans-activator system to boost the expression levels,...levels, and we named the system Tetbow (Tetracycline trans-activator Brainbow) (Sakaguchi et al., 2018) (Figure...expression level of XFPs, most likely by suppressing transcription. It is critical to express a minimal amount ...Bio-Protocol 8 (2018): e3046. Livet, Jean, et al. "Transgenic strategies for combinatorial expression of fluorescent...

...ready-to-use viral preps   Improved cell-free transcription/translation system to examine biosynthetic pathways... Gabrielle Clouse Recently, cell-free transcription/translation systems (also referred to as TX-TL systems...modifications to edit DNA without requiring a double-stranded break. The Xiao Wang Lab has recently deposited.... These plasmids use “Cas9-mediated adenosine transient reporter for editing enrichment”, or XMAS-TREE...and enrichment use of XMAS-TREE. a) Cells are transfected with three different vectors and flow cytometry...identification of essential MYC binding sites in a wide range of human cells.  A new pooled library from Junjie...

... and not in academia is run by grant funding. Learning to write grants quickly, efficiently and effectively...apply to or offer to help with lab grant writing. You may not get the grant or your PI may edit everything...thinking about future career options. 5. Write a grant - even if you don’t need one A lot of science in...valuable skill. There are many different kinds of grants that you can apply for. If you are in a lab, your...Here are some sites that have compiled lists of grants: Science: Where to Search for Funding The Ohio...For Your Research University of Florida: Training Grants and Other Funding Opportunities L’oreal USA For...

...grateful to the grant officers at Fast Grants. We received a miraculous grant from Fast Grants, which was ...studying the coronavirus. Addgene’s Technology Transfer Team also moved fast to ensure that the majority...collaborations as well as provides visibility for grant-driven research being done in all labs sharing materials...materials via Addgene. Perhaps if each of many grantors supporting research could provide Addgene with... for supporting Addgene by providing a generous grant. This support will enable us to continue all operations...

...method is transfection of short interfering RNA (siRNA). Knockdown caused by siRNA is also transient, and ...interest. This approach often involves the transient transfection of expression plasmids in a given cell ...commercially available. Various proteomic and transcriptomic datasets can be used to select a candidate ...antibody should be able to detect even in cells transfected with low efficacy. But since there can be large...differences between endogenous expression and transfected overexpression, this approach cannot confirm ...workshops. Let’s use TIM-1 (Single pass type-1 membrane protein), which has been designated CD365 in the...the antibodies both recognized the target when transiently overexpressed in CHO cells and displayed similar...

...differently. Communication comes in many forms—from transparency about data to allow others to see what you actually...communication and sharing fits together to make for a transparent and collaborative research environment. Journals...Currently, most of the burden for pushing for more transparency in science communication falls on the shoulders...developed STAR Methods to improve the structure and transparency of methods sections, including clear information...researchers are not strongly rewarded for being transparent in their communication or making their data and... to a large extent, hold the keys to getting transparency and communication further up the collective ...management plans and for evidence of sharing for grant renewal—but there is clearly room to do more. If...

...2015, there were six of us. We were initially strangers but we all shared a passion for DIY Biology and...December 2015 we held our first intro to bacterial transformation course (read our blog post on it and to see...consisting of over twenty members and volunteers. Transforming citizens into scientists Anyone can become a...dedicated time at BosLab, he became our bacterial transformation guru and instructor for our intro to biohacking...biohacking courses. Our members pursue a diverse range of projects at BosLab. Some are entrepreneurs using...RNA with small molecules. Other members’ projects range from hacking probiotics to filming educational lab...BosLab. Once he optimizes plant cell culture and transgenesis he wants to share his knowledge with the community...

...covalently joined, scarless DNA – perfect for transforma­­­tion or as a PCR template. Some of the applications...by using NEBuilder which requires only a single-stranded synthetic oligo to generate a single-guide RNA...RNA (sgRNA). Using only one single-stranded oligo, instead of the more typical two oligos, is more cost...annealing step usually used to create a double-stranded oligo. Generating an sgRNA construct becomes as...target region. Assembled plasmids can be directly transformed into E.coli for plating, screening and generation...complexity, is achieved with synthetic oligos with a randomized region between the regions of homology. Producing..., generating expression cassettes for yeast transformation can take 5 days. NEBuilder shortens that time...

...Cas enzymes) cleaves both strands of its dsDNA target in cis and has no trans activity. AsCas12a, on the...cleaves ssDNA in trans. In sum, CasPEDIA documents the target substrate (DNA/RNA and strandedness) along with...Cas enzyme: Nuclease properties (CasID): Cis/trans activity, PAM requirement, gRNA, and multiplex ability...features: CasID CasPEDIA will display both the cis and trans activity of each entry. For example, SpyCas9a (one...can manually enter details to refine your search (trans activity, multiplex ability, gRNA design, etc.).....32942/X2C31F     Makarova, K. S., Wolf, Y. I., Iranzo, J., et al. (2019). Evolutionary classification...

...lactose analogue, IPTG (isopropyl β-D-1-thiogalactopyranoside). (To be completely accurate, IPTG binds...x-gal (5-bromo-4-chloro-3-indolyl-β-D-galacto-pyranoside) into galactose and an insoluble blue pigment...α-peptide) to a lacZΔM15-mutant bacterial cell in trans complements the mutation allowing for a functional...site (MCS) into the α-peptide (represented as an orange wedge in the figure on the left) and inserted it...produces pigment from x-gal (included in the transformation plate medium), turning the bacterial colony...IPTG is also included in the medium to ensure transcription of the lac operon.   Tips for blue-white screening...screening Use a good control: Transform the backbone plasmid without insert. All colonies on this plate...

...split-vector systems’ by separating viral genes and transgene expression across several plasmids. The most commonly...separate envelope and packaging plasmids as well as transfer plasmids. This concept ensures safe handling and...Gamma-retroviral vectors have a relatively high transduction efficiency, but in contrast to lentiviral vectors... are very versatile tools as they are able to transduce dividing and non-dividing cells. More detailed...Gamma-retroviral vectors Popular gamma-Retroviral Transfer Vectors   Expressing your gene of interest pMKO...events and is widely used in the field of mouse transgenics. Experimental uses include: Cre-dependent gene... lab. Learn more about CRISPR plasmids for transcriptional inhibition. Retroviral Plasmid Kit Retroviral...

...students first transform the S. cerevisiae met deletion strains and then isolate transformed strains on media...organism into overexpression plasmids. Students next transform deletion strains from the reference organisms ...to a whole genome duplication and extensive rearrangements in the S. cerevisiae lineage (7). In our class...class research project, students transform S. cerevisiae met deletion strains with overexpression plasmids...expression of the plasmid-encoded MET gene allows the transformed strain to grow in the absence of methionine (... to select yeast that have been successfully transformed with the plasmids, because the S. cerevisiae ...of MET/Met genes from the plasmids allows the transformed strains to grow in the absence of methionine....

...and spread over the second quadrant. The process continues until all quadrants are used, hopefully revealing...students transform them into different strains of E. coli,” says Westenberg. During the transformation experiment...plate, first the bacteria are inoculated over a quadrant of an agar plate. Then, a stick is dragged through...revealing single, isolated colonies in the last quadrant after incubation. The challenge is usually successful...genetic backgrounds of the host strains affect transformation efficiency.  Aside from the Streak Plate Challenge...

...growth rate/transfection efficiency is not known, this is easily achieved by splitting transfected cells into...specific cell line, and its transfection efficiency. We often trypsinize the transfected cells on the day after...after transfection into plates containing selection agent at different densities, then dispose of the plates...under-expressing clones. If GFP-encoding cDNA is co-transfected at a favorable ratio to the gene of interest ...such as the Viaflo from Integra Biosciences) to transition from a 48-well cell plate to a 96-well assay ...expression characteristics from a population of transfected clones. The technique is applicable to a wide...

...epithelial origin. Suppressing function, creating tolerance, and evading recognition are a few methods by ...regulatory cells to suppress function. Creating Tolerance T-regs in the tumor microenvironment produce CTL... This in turn regulates the expression of the tolerance-producing antigens enunciated above. Finally, ...released from the microenvironment help create tolerance beyond direct proximity to the tumor; chemokine-aided...relapse. Chemical and radiation therapies cause a transient shutdown of the immune system, hampering its ability...microenvironment. Antibodies that block cell-surface tolerance-producing proteins are one of the most commonly...cells to knockout proteins involved in immune tolerance. Recently, China spearheaded the first ever CRISPR-based...

...for a growing organism to make the complicated transition from a clump of cells to a fully differentiated...cooperate to cause a higher-energy electronic transition in a fluorescent molecule (see figure to the ...past 15 years efforts have been made to create transgenic mice expressing fluorescent protein reporter ...microscopy enabled scientists to see how chaotic and random the scanning was and how fast T cells could jump...Blue-green fluorescent proteins like EGFP Yellow-orange fluorescent proteins like TagRFP, tdTomato, DsRed...tdKatushka2 (Drobizhev et al. 2011) The commonly used orange and red fluorescent proteins are excited by 750...essential role for neutrophils in leishmaniasis transmitted by sand flies." Science 321.5891 (2008): 970-...

...applicant to the Addgene, Seeding Labs Plasmid Grant. For this grant, we’re working with fellow nonprofit, Seeding...about the Addgene, Seeding Labs Plasmid Grant Read about Plasmid Grant Recipient, Gladys Kaba Resources on...their research. Kwabena came across the plasmid grant in Seeding Lab’s Newsletter and recently visited...Kwabena applied for the Addgene, Seeding Labs plasmid grant. 7:12 - 7:11 : Kwabena's work in Christopher E. ... recipient of the Addgene, Seeding Labs Plasmid grant and is working on a variety of projects in Ghana...

...of customizable DNA-binding domains based on transcription-activator-like effectors (TALEs) as anchors ... thaliana. The results are light-inducible transcriptional effectors (LITEs) designed to bind specific.... Genes under LITE control showed a rise in transcription in as little as 30 minutes after light stimulation... universally abundant. Second, induction of transcription occurs within minutes of light exposure. Third...really flexible and modular,” Konermann said. “Transcriptional activators are easy to expand or combine with...For those who do want to apply LITEs for the transformation of neurons, she offers a tip: save yourself...al. "Optical control of mammalian endogenous transcription and epigenetic states." Nature. 500, 472–476...

... and inhibit its own transcription. As copy number increases, RepA transcription is repressed and replication...indirectly inhibit replication through inhibiting translation of replication machinery proteins, or directly... division. They don’t simply rely on chance (or random diffusion) to make this happen.  There are several...CBPs and NTPase to go around, the plasmids are randomly positioned, leading to plasmid loss (Diaz et al... if these do not provide clarity, a wet lab transformation experiment will ultimately inform whether your... Partition-associated incompatibility caused by random assortment of pure plasmid clusters. Molecular ...classification and identification based on replication and transfer systems and host taxonomy. Frontiers in Microbiology...

... the P and V proteins of Simian virus 5 (SV5) (Randall et al., 1987). The epitope (GKPIPNPLLGLDST) has...10.57733/addgene.l0ulu4. Hanke, T., Szawlowski, P., & Randall, R. E. (1992). Construction of solid matrix-antibody-antigen....org/10.1099/0022-1317-73-3-653. PMID 1372038. Randall, R. E., Young, D. F., Goswami, K. K., & Russell...functional properties, and is amenable to a wide range of biophysical assays (Kroupova et al., 2024). They...using mCherry for selection of sgRNA plasmid transformants, they avoid M. abscessus’ high rate of spontaneous...workflow in M. abscessus. A) Sth1Cas9 mediates double strand break at the target site, which results in either...indels after DNA repair. B) M. abscessus is first transformed with Cas9 on an integrative plasmid containing...