...SpCas9, is NGG. Assuming all nucleotides are represented equally, that’s only a 1/16 chance of having a PAM... NYN/NRN NYN is less effective than NRN Table 1 - Summary of PAM-flexible Cas enzymes Are we truly...editable with CRISPR technology.     Fig. 1: SpCas9 has sparse PAM coverage in the human genome. ...editing landscape. The need for PAM-less editing   Guides for CRISPR are typically selected by the ‘quality...sequence is suitable, but there is no PAM next to the desired cut site, then a further-away gRNA where there ... may wonder: how close is close enough for the desired edit to still occur if the cut site is sub-optimal...it depends, but generally the efficiency of the desired edit is reduced by over 50% when the cut site is...

...Zhang et al., 2015). In this system a modified TIR-1 protein can degrade degron-tagged proteins in an auxin...splitting cGAL4 in two and binding each half to a gp41-1-N-intein. Split inteins are protein domains that naturally...mutations with unc- 119 + selection." MicroPublication 1 (2018): 2–3. Wang, Han, et al. "cGAL, a temperature-robust...of 3’UTRs, the Arizona State University (ASU) Biodesign institute developed a 3’UTR database specifically...specifically for C. elegans. This database provides detailed information about C. elegans 3’UTRs structures, ...imaging processing. The combination of these methods provides unique opportunities to develop computational ...Addgene In addition to the wealth of open resources described above, there were many plasmid tools presented...

...learn more about each reporter or check out table 1 for a summary. HRP HRP tagged RANbodies don’t require...with a standard primary/secondary antibody. Table 1: Summary of the Key Features of HRP, Spaghetti Monster...NIH’s Developmental Studies Hybridoma Bank (DSHB). 1 ml of antibody-containing hybridoma supernatant is...overcomes this limitation and allows for the flexible design and small scale production of antibodies. Problems...Their His tags allow for further purification, if desired, but it's not required for their use. Each RANbody...

...current state (Green when off, dark when on). Figure 1: Photoswitchable MEK1 (psMEK1). Is it possible to ...Below are a few examples demonstrated in Zhou et al. 1. Testing kinase inhibitors Zhou et al examined the...the protein and pdDronpa are preserved. References 1. Zhou, Xin X., Linlin Z. Fan, Pengpeng Li, Kang Shen...Solution: In Zhou et al, the Lin lab present a generic design for creating photoswitchable kinases and use MEK1...create other photoswitchable kinases? The general design of psMEK1 also worked for creating three other ...

... products). I picked this post for a few reasons: 1) I think phage are super cool and have considered ...Connect the Research Community Grad School Advice Part 1: Picking a Lab and a Project That’s it for now. As...record breaking month and to find other posts that deserve a second look. 5 Great Apps for Lab Life This very...Stacey from Eastern Tennessee State University and provides a brief rundown of Sean’s top five smartphone ...Jessica Sacher from the University of Alberta and describes a technique you can use to find phage proteins...molecular biology tool, P1 phage. 2) The post describes an ingenious but simple technique to screen for...that, while affecting a small number of people, deserves our attention and has huge potential for the development...

...cleavage of the transcript.   Figure 1: A predicted conserved secondary structure and sequence conserved...prokaryotic terminators and deposited several with Addgene (1). Prokaryotic polyadenylation Although mostly thought...constitutive RNA transport element lead to enhanced HIV-1 Gag expression in a context-dependent manner. Nucleic...Plasmids designed to express genes in a given host cell type are generally broken down into two broad...post-transcriptional additional of multiple adenine (A) nucleotides to the tail of a messenger RNA transcript. The...structure of the hairpin-DNA complex is thought to destabilize the transcription complex, initiating cleavage...transcription of the template and initiating the desired cleavage event, although some engineered terminators...

..., check out Addgene's CRISPR Guide. Figure 1: Like this jar of jellybeans, a pooled CRISPR library... selecting a CRISPR library for your experiments. 1.  What species are your cells derived from? Currently...a different gene. Libraries may be available in a 1-plasmid system, in which Cas9 is included on the gRNA-containing.... Individual gRNAs are designed in silico using publicly available gRNA design software and synthesized... be independently validated to ensure that the desired modification produces the phenotype you screened...in the first place. With the proper experimental design and validation practices, CRISPR libraries can ...CRISPR Plasmids Read our CRISPR Guide Find tools to design your gRNA ...

... the samples stored in our lentivirus tubes (Fig. 1). However, once thawed, there was a substantial reduction...in the pH of samples stored in our AAV tubes (Fig. 1). It’s important to note that the change in pH only...using the thawed virus within 24 hours. References 1. Murphy BM, Swarts S, Mueller BM, van der Geer P, ...shipment processes. After reading a publication describing how short term storage on dry ice can shift sample...

...s pLKO.1 protocol. Pro-tip: this plasmid grows more slowly than standard plasmids. Find pLKO.1 - TRC cloning...experiments.  Find the scrambled shRNA vector. pLKO.1 - TRC cloning vector - This vector from the David ...2A-Puro (PX459) - This mammalian expression vector encodes both SpCas9 and your gRNA. It’s the former version...

...step to colony PCR is designing primers. There are 3 strategies for primer design: 1) insert-specific primers... less money. The key steps to colony PCR are: 1) design primers to detect the presence of your insert;...the three primers previously described. When using insert-specific primers (1), positive clones (+) will... second option is to design backbone-specific primers. These primers are designed to anneal to sites that...things to consider when performing colony PCR.   Designing colony PCR primers The first and perhaps most ...-specific primers: Insert-specific primers are designed to anneal to an insert-specific sequence. This...backbone but that contain different inserts. When you design primers to anneal outside the cloning site, it ...

...active for greater than 50 generations. Figure 1: Mobile-CRISPRi's modular components. Image from Peters...on a non-selective plate. Most bacteria tested had 1 transfer in every ~100 to 1,000 colonies, but some...including E. faecalis and P. mirabilis, had only ~1 transfer per 1,000,000 colonies. Higher transfer rates... human gut flora. Guides targeted essential and non-essential genes with two guides per gene. The library...expressing guides that target essential genes were less represented while bacteria containing guides targeting... Jason Peters, Oren Rosenberg, and Carol Gross provides a streamlined suite of tools for using CRISPRi...existing bacterial CRISPRi methods. First, its modular design allows for customization with strain-specific promoters...

...unlimited supply of identical antibodies (See Fig 1.). rAbs are a relatively new technology that takes...conveniently modified and engineered.   Fig. 1: Antibody production methods    NeuroMab and others... the signal. If the exposure time is long (e.g. > 1/7s) then the signal is weak and vice versa for a strong...perform differently over time), compatible with the desired applications (such as immunohistochemistry (IHC...antibodies, we have developed a criterion that includes accuracy, strength, and reproducibility. We test...

...homologies. Abbreviated protocol for PITCh Step 1: Generate microhomologies in the PITCh vector ~20...editing possibilities MMEJ can enable. References 1. Sakuma, Tatsushi, et al. (2016).  “MMEJ-assisted ...CRISPR-Cas9 with the PITCh systems.” Nat Protoc. 11(1): 118-33. PMID: 26678082. Find the plasmids from ...such a system is likely to introduce additional nucleotides flanking the insertion. If the DNA ends anneal...MMEJ may also introduce, substitute, or delete nucleotides in addition to the expected deletion, but the...Building on the lab’s previous work, Sakuma et al. describe a detailed protocol for MMEJ-mediated knock-in...PITCh vector via In-Fusion or SLIC cloning. Step 2: Design an insertion locus-specific gRNA The gRNA should...

...expected in another. You’ll need to validate that points 1 and 2 hold true under your specific experimental conditions...application and available resources.     Figure 1: Table summarizing the IWGAV five proposed antibody...like immunohistochemistry on human tissues, when (1) other strategies may not be feasible and (2) large-scale...validation: A view from the mountains. New Biotechnol 45:1–8. https://doi.org/10.1016/j.nbt.2018.08.002  Uhlen...to be present and recognizable by your antibody despite the manipulation. Additionally, not all sample ...large deletion that removes the entire exon that codes for the epitope recognized by your antibody. You...specific, then you expect that the bulk of the peptides identified to be from the target protein. This...

...glassware should be treated with a DEPC solution for 1 hour, and autoclaved to remove residual DEPC. Alternatively...more large, expensive ultracentrifuge.  Figure 1: An outline of the different steps in RNA extraction...extraction: twenty-something years on. Nature Protocols 1:581–585. https://doi.org/10.1038/nprot.2006.83 Additional...Allewell and Sarma, 1974). Additionally, ThermoFisher provides a protocol on how to integrate RNAlater® with ...

...cell with the images from the Allen Cell Explorer (1). When studying the function of a protein or its role...various subcellular structures. Please see Figure 1 for commonly used markers for major mammalian organelles...Subcellular Localization Poster here! References 1. Allen Institute Plasmid Pages 2. Cooper GM. 2000....interest from its production site to its final destination. As an example, most secreted proteins are produced...pathway to their subcellular or extracellular destination. At the end of their life cycle, proteins may... about the subcellular structures your protein resides in and potentially which other proteins it forms...in Figure 2 (adapted from 4) - Dunn et al. 2011 provides an in-depth review of quantitative colocalization...

...Listen to the interview with Darrell Kotton Chapter 1: Introduction to Darrell Kotton and the Boston University...Unit, the Pulmonary Consultation Service, the Alpha-1 Center, and the Pulmonary outpatient clinic, all at...University Center for Regenerative Medicine. Darrell describes his career goals and what drives him as a praticing...

...some technical obstacles when working with virus: 1. Viral vectors undergo DNA rearrangements. Depending...approximately 20–50% of the packaging cells after 1–3 days of selection. A lower percentage of surviving...up-to-date tips for your virus experiments. References 1. Anthony, Simon J., et al. "A strategy to estimate... try amplifying the viral vector with bacteria designed to minimize rearrangements such as NEB Stable ...production of virus. Alternatively, if the virus encodes a fluorescent protein, the packaging cells could...working with, there’s a lot that goes into virus design, production, and transduction. Once you’ve harvested...

...tethered to bring them into close proximity (Figure 1). Formation of the complete FP results in a fluorescent...detected by fluorescence microscopy. Figure 1: How BiFC works. A split FP (e.g., yellow fluorescent... protein interactions in living cells. Nat Protoc 1:1278–1286. https://doi.org/10.1038/nprot.2006.201 ...This post was contributed by Patrick Miller-Rhodes from the University of Rochester Medical Center.  ...plasmids for your experiment at Addgene! How to Design a BiFC Experiment Much like FRET, BiFC experiments...quantification (Kerppola, 2006, 2013). These are described in more detail below: Fusion protein construction...each PIP and empirically test which combination provides the best fluorescent signal. As for linker sequences...

...process is explained more fully in the animated Fig. 1 below. Normalization is a fundamental and often understated...plexWell™ libraries is well suited to large-scale de novo assemblies of short constructs like plasmids...all over the world. The rest of this piece will describe plexWell™ in more detail, and how we are using... containing fragments carrying sample-specific barcodes. Rather than continuing to process 100s to 1000s...