...expression by various mechanisms. The RNA guide is typically 20 nts and the genomic locus must often be proximal... to keep in mind, but likely will not have a significant impact on your data. You are trying to generate...product with CRISPR to (hopefully) be used in human clinical trials. An off-target rate of 5% is far too high...Cas-OFFinder, CCTop, and many more. While such software typically only considers DNA sequence and doesn’t take into...sequencing. While this may be unnecessary for many applications, it is the only comprehensive method available...selectively sequenced to determine if there are significant editing events, serving as a proxy for total ...For a candidate site-specific approach, mRNA quantification or western blot of putative off-targets would...

...and can be specifically targeted to a number of different cell types even when systemically administered... of AAVs contain two numerical designations, separated by a slash, that indicate the ITR and serotype,...experiments. Recombinant AAVs (rAAVs) The primary application of AAV is delivery of genetic cargo to a host...with maximum “trunk” space for genetic cargo. Typically, when researchers speak about AAVs, they are actually...transduced gene is episomal and does not divide and replicate in the same way the host DNA does. Because of ... since you don’t have to wait for the host to replicate the DNA before expression. Now that you’ve got... S., et al. “Various AAV Serotypes and Their Applications in Gene Therapy: An Overview.” Cells, 12(5),...

... antibodies may be indicated on occasion, usually after other signal amplification techniques have been...IgG2 or IgG4. This can be important for some applications. Assay use While secondary antibodies are useful..., the flexibility of their use varies across applications. Western blots, for instance, almost always ...For the latter three, secondary antibodies are indicated when the protein of interest is found in low amounts...been ruled out.  Ease of access Signal amplification isn’t the only benefit of secondary antibodies. Finding...which means that indirect methods are often significantly longer than direct ones.  Even though the secondary...quantitative analysis of a sample. Instead, relative quantification can be done using either the direct or the ...

...from the serum. Protein A/G purification Protein A or Protein G purification is one common method. These... the desired level of antibodies is reached - typically within 2-4 months. After the animal has the desired...reagent that works for your species. Affinity purification Only up to 5% of the IgG antibodies produced...specific for the immunogen. A different type of purification can be performed to isolate antibodies only ...inexpensive. Their short production time and the bulk purification steps keep the cost low compared to other antibody...are particularly useful for certain research applications. Many secondary antibodies are polyclonal, as...target protein thereby greatly increasing signal amplification.  When to stay away from polyclonal antibodies...

...since other signaling networks can also be non-specifically activated and, like the game of telephone, often...must be transmitted by intermediate messengers. Optical control of kinase activity can provide greater ...greater spatiotemporal resolution than pharmacological or genetic approaches, but only a few such methods exist...Problem:  There is no common method for creating optically controlled kinases. The Solution: In Zhou et al...and MEK1 is active or “on.” Dronpa’s color thus indicates MEK1’s current state (Green when off, dark when...kinases good for? There are a number of potential applications for photoswitchable kinases.  Below are a few...endogenous ERK, and its localization serves as an indicator of MEK1 activity. When MEK1 is active, it phosphorylates...

...degraders provide distinct advantages over pharmacological inhibitors including rapidly depleting a protein-of-interest...resistance to inhibitors, and inducing prolonged biological effects. While targeted degradation of endogenous...here. The Methods section of Nabet et al., Nature Chemical Biology additionally provides detailed information...FKBP12F36V binding ligand (ortho-AP1867) via various chemical linkers. Our current lead dTAG molecule is dTAG...FKBP12F36V-tagged LACZ) with dTAG molecules in your biological assay of choice to ensure that there are no toxicities...µM (see Figures 3 and 5 in Nabet et al., Nature Chemical Biology for examples). Monitor neo-substrates ...experiments (Nabet et al. and Weintraub et al.), chemical and genetic rescue experiments (Nabet et al.),...

...pathways and how they lead to neurological phenotypes observed.” Using genetically-encoded biosensors and iPSC-derived...Scientific Advisor. It’s possible that solute channels typically expressed on other cell types can compensate for.... “This proof of concept study will help in identification of new targets that could greatly enhance our...understand so that we could possibly develop pharmaceutical interventions that would inhibit IL-36 release...genes from the X chromosome are expressed at significantly reduced levels in women with TS (Trolle et al...Terry Hébert, a professor and assistant dean of biomedical science education at McGill University.  These...58 individuals with GNB1 disorder since the identification of this disease in 2016. The lab aims to “expand...

...propagated it, separated it into roughly identical replicate groups, and treated these groups with the...among the separate replicates would have different labels - i.e. they would stochastically arise from different...summarized in a recent Nature Medicine paper. In the publication, Bhang and coworkers used the ClonTracer library...below): 1. Resistant cells among the separate replicates would contain the same labels - i.e. they would... Looking at barcode abundances among multiple replicate populations, they found that similar barcodes ...populations were shared by at least one other replicate; prior to treatment, there are small (previously...such that initial resistant populations can be eradicated up-front quickly. This approach is in contrast...

... utilize an array of tools that rely on DNA amplification and manipulation to produce and edit plasmids...plasmids. These are prone to error — both human and biological. Even the most high-fidelity polymerases can ...Potential points where DNA errors can be introduced, indicated by exclamation marks. Error points include places...places where DNA is being created, such as PCR amplification or bacterial growth. Created with BioRender....the correct inserts, tags, promoters, and other critical functional components. Fun fact! Some older plasmids...sequences. These sequences can also be confirmed or theoretical. No matter the level of information that is provided...elements, and nucleotide indels or mismatches in significant plasmid elements. Which differences are considered...

...such as affinity purification mass spectrometry (AP-MS), lack the ability to specifically identify proteins...the validation of a binary PPI as well as the identification of additional interacting factors. Problems...detect weak and/or transient PPIs. Many PPI identification techniques rely on protein interactors to stay... AP-MS. This requirement often prevents the identification of weak and/or transient interacting proteins...lysed before the bait protein is pulled down, typically with an antibody. This can artificially select...controllable version of the BioID protocol. The critical component for both BioID and Split-BioID is BirA...Further characterization of these candidates is critical to understanding how they interact with the bait...

...past decade, primary cells remain difficult to genetically edit due to toxicity from electroporation or ...some cases) and minimal toxicity, including in clinically-relevant lines such as CAR-T cells. Plus, this..., its dimeric nature can interfere with some applications. Several labs have been working to produce monomeric... for molecular fusion and membrane-targeting applications. Nature Methods, 1–9. https://doi.org/10.1038...library generation and screening that led to identification and characterization of AAV.CAP-Mac. Image ...endothelial cell-specific tropism, with slightly reduced efficacy compared to AA9-X1.1. Importantly, AAV1-X1 is ...rodents and broad tropism in primates. Nature Communications, 14(1), 3345. https://doi.org/10.1038/s41467...

... series.  “The only healthy communication style is assertive communication.” - Jim Rohn, Author, Entrepreneur...Assertiveness? An assertive person is able to communicate their ideas confidently while also considering...of the most frequent sources of conflict is miscommunication. For example, you might misunderstand your...the wrong direction. The best way to avoid miscommunication is to follow up after every meeting with an...workplace, these strategies will help you to communicate with confidence earn respect from your supervisor...in an email, there is a high likelihood of miscommunication, which can lead to even more conflicts. If...manager, you can resolve most conflicts if you communicate your ideas assertively, listen to his or her ...

...most transposable elements (TEs) results in the duplication of this target site sequence at the site of insertion...This is similar to how retroviruses, like HIV, replicate. Class I TEs do not encode a transposase enzyme...enzyme.  Class I TEs are considered replicative since every time they jump they make a copy of themselves...retroviruses both in their structure and mechanism of replication. They contain two genes: gag and pol. The pol...they move. Most Class II transposons have a non-replicative “cut and paste” mechanism of transposition: they... it integrates, which produces a target site duplication (TSD). Created in BioRender.com.   Autonomous...transposition activity  Tol2 transposon plasmids    Applications of transposons Now that you’ve learned about...

...Sontheimer EJ, Mello CC (2018) 5′ Modifications Improve Potency and Efficacy of DNA Donors for Precision Genome...repair of a temperature-sensitive pha-1 mutation significantly enriches for knock-in of 2x and 3xFLAG epitopes...Mello lab also reported that modifying the 5’ modification of oligos used to generate linear dsDNA repair...melting and rapidly cooling dsDNA repair templates dramatically boosted editing efficiency (Ghanta et al., 2020... more efficient. Pure PCR repair templates are critical for efficient knock-ins (Ghanta et al., 2020)....Farboud et al., 2019). Work from the Mello lab has dramatically improved RNP editing with linear repair templates...Efficient Marker-Free Recovery of Custom Genetic Modifications with CRISPR/Cas9 in Caenorhabditis elegans. ...

...lines of communication Few people actually like meetings, but run well, meetings can be a critical part of...depositors; Gizela, the lab member who knows how the physical kits are made and shipped; Chiara, the tech transfer...transfer expert who understands the somewhat complicated Material Transfer Agreement process that kits...repository, performing quality control, and providing technical customer service. Team members are highly trained...But this is a blog post, so here are just a few critical features based on my own experience: Leadership...should be on the team. As a team leader, I’ve (diplomatically) booted people off teams. I’ve also kicked ...are helpful, they are certainly not the only communication options. Addgene, along with an increasing number...

...the cell type under study. Many AAVs will show significant expression in a variety of cell types, but you...previous literature using AAVs for DREADD delivery indicates ~7-21 days are required for the onset of gene ...rate limiting step and can immediately undergo replication and transcription. However, with scAAV the effective...by the use of AAVs? 1) Combined functional and anatomical mapping of circuits In our lab, we use AAV-DREADD...these complexes are so robustly expressed that anatomical assessments can be easily performed too. While...identified this feature of AAVs as a new tool for neuroanatomical tracing (11). With the ability to produce neuron...Retrograde AAV Preps at Addgene 2) Comparison of genetically engineered receptors (i.e. chemogenetics vs. ...

... difficult to eradicate. You can suppress the growth of mycoplasma but cannot eradicate it completely....Contamination! Tissue culture media often have indicators included in the media that turns yellow from ...contamination Detection of mycoplasma by naked eyes or optical microscope can be very difficult, so how do you...cells detect mycoplasmas, they trigger a series of chemical reactions and this induces a noticeable color ...contamination, before using the cell lines for assay or analytical purposes. Use 0.1-micron filters as are they ...Fumigate the laminar airflow and the lab facility periodically. The CO2 incubators, used for maintaining cell...cleaned regularly and checked for contamination periodically. For more tips, check out Addgene's video Getting...

...one another, and a value of “1” indicating those markers are identical and completely indistinguishable... tumors, and moreso than other methods, the identification and isolation of rare cell types. In recent...relies on “unmixing.” Unmixing uses a complex mathematical algorithm and single stained reference controls...spectral flow experiment and panel, there are a few critical factors to keep in mind in order to get the best...autofluorescence across various tissue types varies, it is critical to include an unstained sample for each tissue...complexity index ranges from 0-1, with a value of “0” indicating those markers are completely distinct from one...samples. If you are using conjugated dyes, it is critical that your controls and your sample antibodies ...

... molecular biology-grade agarose containing physiological concentrations of salts and glucose. If we circled...diluted from 10X and containing both Hepes and bicarbonate) is brought to room temperature and placed in..., and making sure we always maintain a backup replicates of each clone in case of contamination. We do...fluorescent protein), fluorescence microscopy can theoretically be used to select specific wells from the 48...further analysis. To assess CRISPR/Cas9 knockout efficacy, we have used both Western blotting and PCR, depending...population of transfected clones. The technique is applicable to a wide variety of cell lines, from HEK to ... terms of growth rates, morphology or other physiological properties. An advantage of this technique is...

...in normal biological processes and disease states. While LITE plasmids have clear application to anyone...effectors (TALEs) as anchors for genome engineering applications was still very new. Now, Konermann and her colleagues.... All of this requires genes to be regulated dynamically.” To understand how that works in memory formation...they could package LITEs in viral vectors and genetically target them to specific cell populations. They... the brains of living mice both quickly and significantly. Genes under LITE control showed a rise in transcription...prove the causal role of specific epigenetic modifications in the genome,” Zhang said in MIT’s press release...with LITE? Reference: Silvana Konermann et al. "Optical control of mammalian endogenous transcription and...