...changing transfection ratios can affect transfection efficiency. For some transgenes, transfection optimization...containing structural genes and a transfer plasmid carrying the transfer gene. By dividing the viral elements... structural elements, envelope, and transfer gene are transfected into a packaging cell line, usually ...may not translate to the target cell line. To overcome this issue, we recommend using a range of doses...systems such that it no longer requires the viral transactivator, Tat. For more information on the different...requirement for additional DNA can impact the transfection efficiency of the packaging cell line and thereby...recommended that you try a few different ratios of transfer, envelope, and packaging plasmids in order to ...

...binding to the template strand (strand used by RNA polymerase II for transcription) are more effective for...complex. This complete transfection mix, i.e. csRNP plus ssODN, is then transfected into stem cells. Cells... were transfected in 96-well format using an Amaxa Shuttle device; 5 days after the transfection, the ...template strand. Therefore, I suggest that picking a crRNA complementary to the template strand could increase...Prepare cells for transfection, add csRNP and ssODN to the cell suspension, transfect and let cells recover...selection of transfection buffer and electroporation pulse program to achieve high transfection efficiency... contact me at Pooran.Dewari@ed.ac.uk. Keep pipetting and happy genome editing! Pooran Dewari is a postdoc...

...protocols can transfer CRISPRi into a single bacterial strain, such as a B. subtilis, or a narrow range of bacterial...can be introduced into a broader range of bacteria. Once transferred, Mobile-CRISPRi stably integrates...bacterial Tn7 transposon system. This system has two parts: a plasmid expressing the Tn7 transposition genes ...chromosomal copy of the RP4 transfer machinery mobilize these plasmids for transfer to recipient cells during...: A Tn7 transposon containing the CRISPRi components and a plasmid with the Tn7 transposition genes are...disease. However, the rate of transfer was variable. They measured transfer rates by comparing the number... P. mirabilis, had only ~1 transfer per 1,000,000 colonies. Higher transfer rates are better suited for...

...., 2017), axonal transport  (Murlidharan et al., 2014), and postsynaptic transmission (Oh et al., 2020... S. (2013). Analysis of Transduction Efficiency, Tropism and Axonal Transport of AAV Serotypes 1, 2, 5...Tetracycline-Dependent Transactivator Correlates with Long-Term Doxycycline-Regulated Transgene Expression in ...Specificity of gfaABC1D-Driven Transgene Expression in AAV-Mediated Gene Transfer. Molecular Therapy - Nucleic...great in a GABA neuron, for instance, may not transduce the adjacent norepinephrine neuron at all. There... more than one serotype that will efficiently transduce your cells. In fact, we usually recommend testing...primate. Likewise, in vitro efficacy doesn’t always translate to in vivo efficacy. You’ll therefore need to ...

...expression, Aranda-Díaz et al transformed yeast with both a GAL4/estradiol controlled transcription factor ... a broad pH range. The four biometric probes successfully targeted endosomes under a range of pH conditions...ligand binding domains and the MSN2 transactivation domain. Transcription factor activation via the appropriate...progesterone controlled transcription factor as well as reporters specific to each transcription factor. They then...together. Aranda-Diaz et al additionally show that it is possible to use synthetic transcription factors... levels. That is, if transcription factor 1 controls expression of transcription factor 2, which directly...by modulating the induction of transcription factors 1 and 2. See Aranda-Díaz et al. for more information...

...loxp pair, and flips the transgene into the correct orientation for transcription. Upon recombination one...end of the transgene. Since loxp and lox2272 can not recombine, this ensures that the transgene is no longer...flank a transgene (homologous pairs) or used different scrambled sequences to flank the transgenes (non-...Rumpel S (2013) Analysis of Transduction Efficiency, Tropism and Axonal Transport of AAV Serotypes 1, 2, 5...gene expression in a specific cell type rely on transgenic models that express recombinases like Cre or ...recombinase-dependent AAV vectors for selective transgene expression. While this is a powerful experimental...sequence prior to an ATG start codon to prevent transcription in cells where the recombinase was not present...

...optimized your transduction conditions, you’re ready to transduce! Addgene has a transduction protocol you... the pooled library is transformed into E. coli for amplification. Transformed E. coli are allowed to ...functional titering and optimize transduction efficiency. Transduction efficiency can vary with titer, ...cells to transduce, you may want to consider spinfection. Spinfection is the process of transducing cells...this post, I’ll walk you through how to prep and transduce your pooled library.  Pooled libraries Scientists...lentiviral production steps before you can start transducing your virus. Let’s start there!     Figure...sequencing to confirm library representation. Transfection of the DNA pooled library and appropriate packaging...

...effects of the transfection itself (i.e., the vector used in transfection, transfection reagent, or transfection...experiments employ transfection, negative, positive, and replicate controls.  Transfection controls: empty...vector and internal control A transfection control measures transfection efficiency and enables observation... allows you to examine if the transfection reagents or the transfection process itself has any cytotoxic...Another type of transfection control is an internal control vector, which measures transfection efficiency....luciferase) that is either co-transfected with the test plasmid or transfected into a separate well of your...due to the original transfection conditions. Now that we have successfully transfected our cells (Figure...

...control exactly in which locus your transgene ends up (1): Random insertion has the advantage that you...you need to combine multiple transgenes in one fly, having the transgenes in different loci allows for...use? Random insertions take longer because you need to determine in which chromosome your transgene has...brief introduction as to how you can engineer new transgenic flies to study your favorite gene (YFG).  Sometimes... is thrillingly new, you might have to make a transgenic fly in order to study it. The process is fairly...plasmids at Addgene Choosing a vector to generate a transgenic fly There are a few important points to consider...genome? Some vectors incorporate into the genome randomly, while others use attP sequence docking sites ...

...light to regulate transcription, also includes light-regulated histone methyltransferases and deacetylases...CRISPR Epigenetics resource. Transcriptional activation p300 acetyltransferase dCas9 fused to the catalytic...other Tet1 delivery systems. Transcriptional repression DNA Methyltransferase 3 Alpha (DNMT3A) Vlatka Zoldoš... PuroR enable sorting and selection of transduced cells. Grant Challen’s lab also created constitutive...associated with transcriptional repression. Created with BioRender.com. DNA Methyltransferase MQ1 Margaret...Fusing dCas9 to a transcriptional activator like VP64 or VPR activates transcription, whereas dCas9-KRAB...domain, could mediate demethylation and induce transcription at CpG regions of various promoters. Other researchers...

...most cases, interested in transferring genes to mammalian cells (i.e. transferring DNA), yet retroviruses...still direct the translation of proteins because they integrate this reverse-transcribed DNA into the host...genome and then use cell machinery for transcription and translation. Here, we will discuss several aspects...worthwhile to generalize the idea of “transduction” to mean any transfer of material from the virus to the...a turn of phrase — “pseudotransduction” — to describe the direct protein transfer of RT, which would actually...After uncoating, reverse transcription follows the release of the two strands of viral RNA and of the ...structural proteins expressed from a reverse-transcribed piece of DNA called a “provirus.” This DNA is...

...modify a given gene. CRISPR-tranposons By combining CRISPR editing and transposons, the Sternberg and Zhang...developed CRISPR-transposons. The Sternberg lab's system called INTEGRATE (Insertion of Transposable Elements ... CAST (CRISPR-associated Transposase) both enable gRNA-directed transposition. INTEGRATE consists of four...multi-spacer CRISPR array, CRISPR-transposons can be multiplexed. Transcriptional repression (CRISPRi) in bacteria...proteins involved in the activation of transcription including transcription factors, phage proteins, and RNAP... unlike other organisms, CRISPR-induced double stranded breaks are lethal because the non-homologous end-joining...ineffective in bacteria, CRISPR-induced double stranded breaks (DSB) are lethal. Addgene depositor Luciano...

...Addgene Help Center: Tech Transfer Technology Transfer Information Tech Transfer News: A Reintroduction ...Addgene account for Tech Transfer Offices. They’re packed with tech transfer resources (summaries, electronic...question? Refer them to Addgene’s Tech Transfer Team: techtransfer@addgene.org Congratulations to the Golden...stats and strategies with tech transfer offices. Drop us a line at techtransfer@addgene.org. Albert Einstein...requests from Addgene MTA: material transfer agreement Technology Transfer: the exchange of intellectual property...addgene.org identifies the hold-up. Your Material Transfer Agreement is stuck in “pending.” Fear not, there... to make MTA turnaround faster with technology transfer offices (TTOs). The latest of these efforts is...

...protein Tat. Although CPP fusions can translocate a cell membrane, the presence of the CPP may alter protein... (78-79% after two rounds of transduction.) Compared to CCP transduction, iTOP is at least four times ..., and cell death post-transduction is low. Neuronal stem cells transduced with iTOP resulting in...lab suggests that primary cells may be better transduced using only protein. Read on for a description...description of the lab’s iTOP protein-only transduction method and its potential applications to CRISPR/Cas9 genome...genome editing.   Protein-only transduction? Niels Geijsen’s group in Utrecht wanted to pursue a nonviral...nonviral strategy for transducing primary cells. What if, instead of supplying a DNA construct, they could...

...can find the subsequent transformation protocols below: OpenWetWare Transforming chemically competent ...Untergasser Lab Transformation of chemically competent cells (protocol)  Transformation of electrocompetent... easily transformed without a heat-shock step. Because of the large number of transformations being performed...that transforms well in other competent cells) to ensure that your cells can be readily transformed. Compare...Want even more tips for transforming your cells? Check out our transformation guide.   ...We perform over 100 transformations each week at Addgene, so we need to be cost and time efficient. We...a little-known reagent for streamlining the transformation step. Read on to find protocols and tips that...

...reagents can be delivered via transfection, nucleofection, viral transduction or injection as either protein...cell line that can be transfected at high efficiency. Lentiviral transduction Cas9 and gRNA can be present... present in a single lentiviral transfer vector or separate transfer vectors. May contain reporter gene...inserted into an AAV transfer vector and used to generate AAV particles. Transient or stable expression...Chemical transfection   Lipid mediated Cationic polymers Calcium phosphate Cells Transformed cell lines... lines Transformed cell lines Transformed cell lines Cargo Nucleic acids or protein Nucleic acids Nucleic... method: Do you need stable integration or is transient expression sufficient? Which cell types will you...

... not appear to mind extraneous proteins bound to its outer mitochondrial membrane. Sequestration is accomplished...Updated mini-transposon vector for bacterial mutagenesis or gene targeting Victor de Lorenzo's lab...modular mini-Tn5 vector that can be used to generate random mutagenesis libraries or to insert heterologous...selecting the important elements from existing transposon and vector systems and creating an all-synthetic...validated this vector, called pBAM1, by conducting random mutagenesis in the soil bacterium Pseudomonas putida...family of GFP proteins in the cephalochordate Branchiostoma floridae, named bfloGFPs. They went on to characterize...mitochondrial turnover Mitochondrial health, transport and turnover are important features to be monitored...

... could infect. Finally, the transfer plasmid encoded the desired transgene flanked by HIV-1 long terminal...integration. After co-transfection of these plasmids, 293T cells released transgene-containing lentiviral...protein), Pol (polymerase), Tat (viral transactivator for transcriptional activation from the 5’ LTR) and Rev...capacity of a lentiviral vector but for which transient transgene expression is sufficient. Lentiviral vector...include a large genetic capacity and the ability to transduce both dividing and non-dividing cells. Lentiviral...integrate into the genome, permitting long-term transgene expression, but they could only infect actively...infect non-dividing cells, but without sustained transgene expression. To design a viral vector system that...

...PHP.B has a >40-fold increase in CNS transduction and transduces the majority of astrocytes and neurons... mice whose CNS was transduced by PHP.B but absent in mice who were not transduced by PHP.B. The Deverman...These results were surprising because in vivo transduction of AAV serotypes generally tracks between strains...diverse library of AAV9 mutants that had a small randomized peptide loop inserted in the AAV9 capsid. This... an enhanced version of PHP.B, shows similar transduction efficiency, but at a log lower dose than PHP.B...permissive and six as non-permissive to PHP.B CNS transduction. Two genes were associated with the PHP.B permissive...outbred mice (F1) had half the level of CNS PHP.B transduction as their C57BL/6J parent. The second generation...

...libraries, chemical transformations can also be used. Efficiency for chemical transformations is less than that...for your transformation(s). The amount of competent cells you need total and per transformation may vary...the manufacturer’s protocol for transformation and expected transformation efficiency, or more specifically...with a large backbone might be more difficult to transform.    Figure 1: Factors to consider when ... coverage, since this will help decide what transformation efficiency you need to achieve. Most pooled...contains 5,000 plasmids, your goal for your transformation would be to obtain 100 x 5,000 = 500,000 colonies...likely rely on serial dilutions to estimate transformation efficiency (Figure 2).    Figure 2: ...