We narrowed to 814 results for: Ran;

...non-target strand. The helicase domain is then activated, and Cas3 begins unraveling the double-stranded DNA ...cleaving the ssDNA strands. In this way, Cas3 eats away at both the non-target and target strands by making cuts...every so often. Cutting both strands ensures that there isn’t a template strand left behind that the cell... regions on the non-target strand. Occasional cleaving of the target strand is not as well understood ...bypassed by leaving out Cas3 — a tactic some CRISPR transposase systems utilize with type I-F Cascades. ... section for details). The newly formed single-stranded DNA (ssDNA) is then pulled through Cas3. After...implies — after nicking, Cas3 reels in the non-target strand of DNA much like a fisherman would reel in a big...

...which cleaves one strand of DNA upon binding the protospacer. The resulting double strand break (DSB) stimulates...two catalytic domains, HNH and RuvC, cleave DNA strands complementary and non-complementary to the gRNA... binds the target site, but does not cut either strand of DNA. Traditional Cas9 regulators In addition... then be fused to effector domains such as transcriptional activators or repressors. These fusion proteins...loci within a single cell. One might imagine transfecting cells with both the nuclease-positive and nuclease-null...Consequently, fewer genetic tools for targeted transcriptional and epigenetic regulation have been validated...inexpensively generate a potent Cas9-based transcriptional regulator without making any functional changes...

...contacts that bring apposing membranes together and can wrap the membranes into stacked structures including...dimerization.   1. Transmembrane fluorescent protein fusions Transmembrane proteins, i.e. receptors...receptors and transporters, are integrated into lipid bilayers. Fusion of an FP to a transmembrane protein significantly...Green Fluorescent Protein (GFP/EGFP) for a transcriptional reporter or as a general cytoplasmic label ...making FPs monomeric, yet many investigators remain ignorant of FP dimerization. Equally problematic, several...they cannot tumble in 720°, i.e. they are on a membrane or in an organelle, then their effective concentration...dimerizing fluorescent proteins is illustrated. 1) Membrane proteins fused to FPs that dimerize can form dynamic...

...activation of transcription in bacteria by co-opting σ54-based transcription. Transcription from σ54 promoters...enables researchers to maximize the chance of transducing a only a single gRNA per cell. The viral DNA ...genomic DNA. However, some cell types are poorly transduced by lentivirus, and thus screening with available...not possible. Primary murine T cells cannot be transduced by lentivirus and have been difficult to manipulate...Yusa Lab. This retroviral library was used to transduce T helper type 2 (Th2) cells from mice that constitutively...screening of cells that are refractory to lentiviral transduction, now enabling forward genetic screens in cells...they develop rapidly, they are small, and their transparency allows for whole organism imaging. They created...

...containing transcription factor binding sites can increase transgene expression and transduction efficiency...as the gene that they package. In a transfer plasmid, the transgene is flanked by two ITRs, and the ITRs...vectors, modifications can affect gene transfer efficiency and transgene expression (Zhou et al. 2017). For...these mutations can affect transduction efficiency and subsequent transgene expression. Replacing the ...nucleotide sequences that flank the ends of the single stranded DNA genome of AAV in the native virus. Since the... the feature its characteristic T-shape. The arrangement of the B-B’ and C-C’ palindromic sequences determines... reduce the packaging efficiency but increase transgene expression (Zhou et al., 2017). The most common...

...engineered combinations of transcriptional activators to induce gene transcription at genomic sites targeted...p65-HSF1 transcriptional activator to each genome-bound dCas9 (see Figure 1a for the transgenic construct...different untranslated or coding regions. Typically, each gene isoform has a distinct transcriptional start...investigation. Co-transduction of primary rat neurons with dCas9-VPR and sgRNAs targeting either transcript variant...activation (CRISPRa) tools for neuroscience, including transgenic mice, neuron-optimized viral vectors, and high-throughput...with the development of a Suntag-p65-HSF1 (SPH) transgenic mouse (Zhou et al., 2018). This mouse expresses...CRISPRa to selectively target these different transcriptional start sites in order to better understand isoform-specific...

...structures in RNA transcripts Effects on transcription (remember, it’s not all about translation - e.g. codon... you cannot choose among the possible codons at random and expect your sequence to express well in any...therefore may need fewer resources for the entire translation process. For example, during high growth rate... tRNAs. For example Tuller et al. found that translation efficiency is well correlated with codon bias...tRNAs, different regions of the protein may be translated at different rates. The ribosome will move quickly...the ribosome stalls, this may give the swiftly translated regions a chance to fold properly. For example...codon preferences online). Even if the gene is translated, it may not function properly. This is the result...

...changing its double-strand cut to a single-stranded nick. In order to produce a double stranded break, two sgRNAs...place on the free strand of DNA and converts a C to U without producing a double strand break.   Prime... target DNA. The reverse transcriptase polymerizes DNA onto the target strand based on the sequence of...targeting dCas9 to transcriptional start sites was sufficient to repress transcription by blocking its initiation...approach is that two sgRNAs targeting opposite strands must be available in moderate proximity to each...desired edit adjoined to the sgRNA, a reverse transcriptase, and a nCas9. While this system has been shown...been exploited to localize factors such as transcriptional activators and repressors to target genes. ...

...RNA polymerase III transcript, the sgRNAs were encoded on the lentiviral minus strand in the 3’ LTR. These...HeLa cells transduced with SARS-CoV-2 nucleocapsid protein (Plasmid #141391-LV [+N]) or membrane protein ...high microglia transduction efficiency for the indicated ssAAV5s. Figure adapted from Serrano et al. 2023... with tRNAs, which are cleaved out of the RNA transcript by endogenous processing enzymes (Figure 1). ...including modifications to the Cas9 or reverse transcriptase enzymes, inhibition of host cell proteins, and...microglia are notoriously resistant to viral transduction. Through in vivo screening of human promoters...scAAV vectors have limited size compared to single-strand AAV (ssAAV). To maintain the packaging capacity...

...small, double stranded RNA molecules that degrade target mRNA transcripts. When transiently introduced, ...fused to a transcriptional repressor to your gene of interest. It will inhibit transcription instead of...of introducing a DNA double strand break. Transient introduction of CRISPRi or inducible expression (more...LoxP vector.   Turn it off for a little while Transient suppression of expression is faster and easier...expression. Addgene has a dCas9 KRAB plasmid for transient knockouts!  Turn it on Turn it on forever Permanently...for integration at a specific genomic site, or randomly integrated (once or many times) into the genome...that, too! CRISPR activators (CRISPRa) are transcriptional activators fused to a dead Cas9. The system...

...and GFP reporters, as well as multiple transient and transgenic systems, Sahoo et al. showed that gene...commonly used 35S promoter. Transgenes are also efficiently inherited in both transgenic tobacco and Arabidopsis...tumor-inducing” or Ti plasmid, which allows it to transfer genetic material into the host plant genome. Scientists...Scientists have worked to optimize this system for gene transfer, studying the stability of modified Ti plasmids...a new and versatile binary Ti vector for both transient and stable gene expression applications in plants...borders specify the region of DNA that will be transferred to the plant, similar to viral vectors’ terminal...binary vectors are quite large (>10 kb.) Since transformation efficiency is inversely proportional to size...

...non-exclusive gene silencing pathways: transcriptional and post-transcriptional gene silencing (PTGS). In either...silence the target gene(s) either transcriptionally or post-transcriptionally. In plants, different dicer-like...where approximately 20-30 nucleotides of double-stranded RNA (dsRNA) results in downregulation, or “silencing...either pathway, short double-stranded RNA fragments (siRNAs) are produced from long dsRNA via an RNase III... through targeted mRNA degradation, blocking translation, or chromatin modifications of complementary ... Figure 1: Schematic of an RNAi-inducing transgene. Typically, the desired target of RNAi is expressed...alternative start codons, and/or the phenomenon of transcriptional adaptation (Smits et al., 2019; Sztal and Stainier...

...affiliated TniQ protein recruits transposition cofactors. The transposon proteins integrate a payload sequence... like we finish writing about one dual CRISPR-transposon system before another exciting new advance emerges...combined with the large sequence capacity of transposons open whole new worlds to explore. The newest ...called evoCAST — an evolved CRISPR-associated transposase (CAST). Back up a second. What are CASTs? CASTs...bacteria. In the course of evolution, Tn7-like transposons captured and repurposed nuclease-deficient CRISPR-Cas...Conveniently, the process doesn’t cause double-stranded breaks and can deliver large sequences and even...Cascade shown) combines with a donor template and transposon proteins (Tns) to integrate large sequences into...

...signal downstream of the transcription start site will terminate transcription of most of the ncRNA (Figure... coming, right? Non-coding RNAs (ncRNAs) are transcribed but do not encode proteins. They play important...Using a single guide RNA (sgRNA) to create a double-strand break works well because very small deletions and...sequence can completely disrupt expression of the transcribed ncRNA (Jiang et al. 2014).  Simple knock-out ...lncRNA regulatory elements that are crucial for transcription and downstream function. Rather than attempting...the lncRNA locus, scientists can mutate the transcription start site, splice sites, exons, and/or promoters...the removal of exons. Disrupting promoter or transcription start site function would also help to reveal...

...the zeptomolar range while One-step-SHERLOCK has a sensitivity in the femto-aptomolar range. For more details...are designed, each binding to one strand of the reverse-transcribed target sequence that are present close...reverse transcription. This is then amplified by PCR using Taq Polymerase and then transcribed to provide...LED and an orange filter to detect fluorescence upon cleavage. Highlights: Reverse-transcribed RNA samples... Suresh from Iowa State University. Since its appearance, SARS-CoV-2 has spread to almost every part of... milliliter can be detected – in the zeptomolar range Time: ~1 hour Equipment required: 37°C water bath...amplified. RPA reactions also contain reverse transcriptase to produce cDNA. Isothermal amplification is...

...proteins to process a double-stranded intermediate into the single-stranded genome that's then packaged...viral replication; and 3) the transfer plasmid which encodes a transgene of interest that’s packaged into...XmaI restriction sites). Another way is to transform AAV transfer plasmids into bacterial strains, like NEB...Overview: The first step in packaging AAV is transfecting HEK293 cells with AAV packaging plasmids. The... into the virus. Two to five days after transfection, the AAV-containing cells and media are harvested...more details. Pro tips I’m not going to lie, AAV transfer plasmids are kind of a pain to work with. These...structures that are prone to deletion from the transfer plasmid. The good news is there’s a few simple...

...Transcription factors (TFs) act as the gate keepers for gene expression, turning transcription on and... regulatory network. The transcription atlas and library The transcription factor library The human...lentiviral particles and used to transduce human embryonic stem cells. Transduced stem cells were differentiated...approximately 1,800 TFs, with >3,500 unique isoforms transcribed from these sites. The Zhang lab generated a comprehensive... contribute to differentiation, the Zhang lab transduced human embryonic stem cells with the viral TF ...differentiation outcomes as well as global transcriptional changes. Using this road map, and what was ... uncharacterized TFs is a useful finding. Transcriptional program changes from this screen successfully...

...is codon usage important? Translation and protein synthesis relies on transfer RNAs (tRNAs). tRNAs bind...rate of translation and thus protein expression. In fact studies have shown that translational efficiency...on an organisms codon usage bias to increase translational efficiency and thus protein expression without...mammalian cells. This was the first codon optimized membrane protein expressed in mammalian cells. In this ...conformation, folding and stability, change post-translational modification sites and even affect protein function...Mauro and Chappell, 2014). Different rates of translation by different tRNAs, including those that exhibit...actually be critical for determining the rate of translation. The ribosome may slow and pause during elongation...

...concentration of FLEx vectors guarantees that most cells are transfected with all labeling plasmids and...PMCID: PMC2593125. 2. Buchholz, F, P O Angrand, and A. Francis Stewart. 1998. “Improved Properties of ... sites can lead to excision, inversion, and translocation of DNA in a similar fashion as between loxP ... has a temperature optimum of 37 °C (Buchholz, Angrand, and Stewart 1998). FLPe’s performance was further...in FLPO, which shows similar efficiency to Cre (Kranz et al. 2010). These differences in recombinase efficiency...-LDB domains of the fusions allowing Cre/FLP translocate to the nucleus where they exert their recombinase...brain? Cells of a specific brain area can be transfected by in utero electroporation. To achieve sparse...

...Importantly, they allow transient delivery, enabling transgene-free genome editing (no transgene integration), ..." (one for each strand), while TnpB, like Cas12a, uses just one to cleave both strands. Similar to how...lab recently harnessed TnpB from Deinococcus radiodurans (Dra2TnpB) to create a genome editing system ...also need a short sequence motif called a TAM (transposon-associated motif), which is positioned like Cas12a...species. For instance, the TnpB from Deinococcus radiodurans (Dra2TnpB) recognizes the TAM sequence 5′-TTGAT...parts: a structural scaffold derived from the transposon's right-end element, and a 20-nucleotide (nt) ...downstream of the TAM, creating staggered double-strand breaks like those created by Cas12a. Applications...