...currently doing this using two approaches: single-cell RNA-sequencing to identify neuronal class and deep...WDDD aims to acquire quantitative data on all the cell divisions of the C. elegans embryo when all essential...Wang et al., 2018).” With the split system, only cells that have both halves of cGAL can drive expression...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...C.elegans neural network, and Sibernetic, a fluid mechanics simulator that can be used to simulate muscle ...

...Making contact with a cell Although an individual AAV particle’s ability to infect a cell is dependent on its...construction and the cell it’s infecting, getting these particles to infect cells is also very titer-dependent... particle to infect a cell, it has to come into physical contact with that cell. Since there is a limited...of surface area on each cell, the way to get more AAV in contact with the cell is to increase the AAV ...between the cell and any individual AAV particle is rare. But simply getting into the cell may not always...particles that have entered the cell now have to travel up the axon, through the cell, and potentially spread ...particles per cell, you may not be able to detect AAV-mediated gene expression in a target cell. Practical...

...the producer cells and purification protocols often describe a process that begins with cell lysis to release... steps to separate cell culture supernatant containing exo-AVVs from producer cells, and then to enrich...effectively target less accessible cells, such as brain tumor stromal cells in a mouse model of glioblastoma...particles is able to infect more cells (as demonstrated in different cellular environments such as retina ...Exosomal vesicles secreted from producer cells also contain cellular macromolecules (e.g. proteins, nucleic...Standard AAV vectors are generated with a producer cell line like the widely used 293T. During vector production... to be spontaneously released from the producer cells into the supernatant during the production phase...

... the cell bodies of the projection neurons reside.   Impact for scientists While the mechanisms by which...they either trace downstream from the soma (neuron cell body) toward the axon (anterograde tracer) or upstream...particles require receptor-mediated entry into the cell. This means that not all neurons and pathways will... There are two methods of neuronal tracing (Fig. 1): one to visualize neurons that send information to...significantly updated in 2023 by Jason Nasse.  References 1. Tervo, D. Gowanlock R., et al. "A designer AAV variant...

...Inhibitor of CRISPR-Cas9. Cell 170:1224-1233.e15 . https://doi.org/10.1016/j.cell.2017.07.037 Li C, Psatha...Off-Switches for CRISPR-Cas9. Cell 167:1829-1838.e9 . https://doi.org/10.1016/j.cell.2016.11.017 Shin J, Jiang...concern is that the longer Cas remains active in a cell, the greater chances there are for off-target edits...within the first six hours. When added to human cells six hours after the introduction of Cas9 RNPs, AcrIIA4...CRISPR/Cas9 Toxicity in Human Hematopoietic Stem Cells. Molecular Therapy - Methods & Clinical Development...cleavage (Harrington et al., 2017). Figure 1: Anti-CRISPR proteins (Acr's) can block CRISPR activity... ways to anti-CRISPR proteins in your experiments 1. Reduce off-target effects Prolonged Cas activity ...

...patterning of cells and tissues is fundamental to development. I'm interested in how cells find their way...Position" eBook Here 1. Have a competitive CV You don't necessarily need a Nature/Cell/Science paper. You... optimization of fluorescent proteins,  and live cell imaging approaches. Erik is also an avid long distance...that people would agree is important to understand. (1-2 sentences). For example: Distinguishing correctly... What will be the focus of your first grant? (1-2 sentences) Simply stated, what are your aims...human disease" is vague. Instead, consider "A mechanistic understanding of this system will provide the...

...development. Single cell sequencing-based lineage tracing Recently, gene expression in all cells of the developing...proportions of otherwise normal cell types are produced, rather than novel, abnormal cell types. Sequencing-based...applications. For example, specific tissues such as blood cells or neurons can be fluorescently labeled, allowing...divisions, and movements of each of the thousands of cells in the developing zebrafish embryo have been tracked...developing zebrafish embryo has been mapped using single cell RNA sequencing approaches (Harland, 2018). Several...sequenced zebrafish genome. One study profiled 38,731 cells from 694 embryos over multiple stages and reconstructed...reconstructed the patterns of gene activity and cell divisions that coordinate development of the body plan...

...Xenopus frog cell lines to develop robust methods for frog gene editing. They edit in a cell line, then ...is the smallest photosynthetic cell in existence, but most abundant cell on earth (twice the human biomass...Hawaiian bobtail squid has an extreme number of nerve cells and an unusually high level of RNA recoding in the...using novel vesicles to efficiently transform these cells which don’t like foreign DNA at all (maybe because...total). Hydra (Celina Juliano) This is a known stem cell and regeneration model. Little bits of hydra can...know that most cephalopods die after they lay their 1 clutch of eggs? Propagation is thus quite difficult...organism blog posts: Five Popular Model Organisms, Part 1 Five Popular Model Organisms, Part 2 ...

...overexpress YFG in a Drosophila cell line. Knock downs in Drosophila cell lines are extremely effective....person. Animals are diploid except for their germ cells (sets of genomic material are contributed by mother... of their abdomen will be a dark spot. This is meconium (in other words, newborn poop) visible through...

...genes should be ‘read’ by the cellular machinery. This is how most cells in the body contain the same ...visualise changes in histone methylation in living cells. Essentially this reporter construct consists of...recognise lysine 27 methylation. When tested in living cells where methylation of these sites was controlled,...fluorescent reporters of histone methylation in living cells." Journal of the American Chemical Society 126.19...treatment and improving patients lives. References 1. Ong-Abdullah, Meilina, et al. "Loss of Karma transposon... within an organism. Mechanisms of epigenetic modifications The main mechanism of epigenetic modification...complex of DNA and histone proteins that compacts cellular DNA into chromosomes and reduces the risk of dangerous...

... a common thread at the meeting. The new Somatic Cell Genome Editing program, run through the NIH Common...Improve HDR Efficiency for CRISPR Editing in Human Cells Hands-on tips for repair template design from guest...B. Gurumurthy, and Masato Ohtsuka. Nat Protoc. 13(1) (2018):195-215. PubMed PMID: 29266098 Creating knock-in..., with protocols using dsDNA templates achieving ~1-10% efficiency. Easi-CRISPR uses a long ssDNA template...to learn much more about cellular DNA repair pathways. An emphasis on cellular repair post-CRISPR cleavage..., which alter genomic DNA without the need for cellular HDR.   Having had time to digest my notes, since...a brand new CRISPOR manual to kick off 2018! "Mechanisms of precise genome editing using oligonucleotide...

... specific cell-type promoter. Once injected into the brain, the viruses infect all the cells with an inactive...proteins control the flow of electric charges across cell membranes and maintain membrane potential in response...once a certain number of positive ions crosses the cell membrane, a threshold is reached and the neuron ...selective expression of opsin genes in targeted cells makes it possible to control neuronal activity with... This could be overcome by fusing opsin genes to cell-type specific promoters; however, those usually ...drive weak expression of downstream genes. Strong cell-specific promoters, on the other side, are too long...achieve strong opsin expression in specific neuronal cell types then? This is where FLEx enters the scene....

...mammalian cells. This was the first codon optimized membrane protein expressed in mammalian cells. In this...sequence. That means there are 61 possible tRNAs. Cells however, may not express all 61 of these tRNAs and... are also optimized for expression in mammalian cells. For example, Henry Lester’s lab optimized the C...Caenorhabditis elegans GluCl ion channel genes for mammalian cells dramatically improves expression levels. Journal... cerevisiae (Tuller et. al., 2010). Figure 1: An overview of peptide synthesis. A ribosome interacts...McClain WH (2000) The G·U wobble base pair. EMBO Rep 1:18–23 . https://doi.org/10.1093/embo-reports/kvd001... W, Mauro VP (2005) An mRNA-rRNA base-pairing mechanism for translation initiation in eukaryotes. Nat ...

...quality work in cell culture. The problems with cell lines Simply put, the majority of cell line problems...HeLa cells, the first immortalized human cell line. He proved this by examining whether the cell lines...Cancer Cells, Marker-independent identification of glioma-initiating cells. The International Cell Line ...Animal Cell Culture Guide Thermofisher Guidelines for Maintaining Cultured Cells Invitrogen Cell Culture...working cell bank has been made by a research institution (an excellent practice), or maybe cells have been... Outreach Scientist Nick Amiss. Cell culture in the present day Cell culture is a widespread tool used... ability to propagate viruses in cell culture; if there were no cells to infect, there would be no viable...

...the sample (by less than 1%) and recovered after the magnet was removed (Figure 1). At first, Andrew and...visible whether expressed in E. coli, in mammalian cells, or in purified form, and didn’t need any added ...since the initial report in 2023.)     Figure 1: Fluorescence intensity of EGFP-FlavinTag in E. coli...that could be expressed and purified. Although a ~1% change in signal might not make a very powerful tool...Hayward et al. 2024 under CC-BY license.   Video 1: Fluorescence movie of E. coli expressing MagLOV while...admit they don’t fully understand the physical mechanism, though they have collected a variety of data ...biomedical engineers, join efforts to explore the mechanisms and develop potential applications.  Andrew is...

...millions of cells. For every individual sgRNA, you recover a minimum of 1,000 targeted cells to sequence...trying to generate a knockout cell line, with the goal of isolating single cell clones to use for multiple...generate a ssDNA break which can easily be repaired by cells with a near zero likelihood of mutation arising.... a level of, say 5%, then the majority of single cell editing events will be on target. Thus, if you isolate...example, if your goal is to generate a knock-out cell line to perform downstream characterization of, ...downstream experiments. You only successfully generate 1 null clone and proceed with it. In this case, the ...there are 10 putative off-target locations you can 1) determine if editing at those sites would confound...

...This novel tool is practical in cell and organ culture, as well as cell lineage studies. Eisenhoffer and...CreLite for cell tracing using the transgenic zebrafish model, ubi:zebrabow. In this system, cells express... Figure 1: The base editor is split into two plasmids and co-transfected into cells for reconstitution...fast-splicing split intein and co-infected into the cell. Intein splitting removes any exogenous sequences...red-light inducible optogenetic tool for precision in cell lineage tracing Article contributed by Erin Sanders...fluorescent proteins controlled by Cre recombination. Each cell can have multiple copies of the transgene that recombine..., such as the brain, eye, muscle and epithelial cells, as well as in different stages of development, ...

...mammalian cells. Co-expression markers EGFP and PuroR enable sorting and selection of transduced cells. Grant...in the Mammalian Genome. Cell 167:233–247.e17 . https://doi.org/10.1016/j.cell.2016.08.056 Find plasmids...targeted DNA demethylation. Cell Discovery 2: . https://doi.org/10.1038/celldisc.2016.9 Find plasmids from...for targeted cytosine demethylation in mammalian cells. This plasmid is used with pcDNA3.1-MS2-Tet1-CD ...vectors and targeted delivery into hard-to-manipulate cell types. They have also fused LSD1 to x-Cas9(3.7)....modifiers may be more frequently inherited by daughter cells. For example, KRAB induced silencing was transient...enhancers. As the effects of these tools are likely cell type- and context-dependent, it may make sense to...

... Guide RNA and Target DNA. Cell 156:935–949. https://doi.org/10.1016/j.cell.2014.02.001  Ran FA, Cong ... Delivery by AAV Vectors. Cell 181:136–150 . https://doi.org/10.1016/j.cell.2020.03.023 Additional Resources...acids) displayed cleavage activity in mammalian cells. SaCas9 produced indels at a similar efficiency ...package each piece into an individual AAV. When a cell is transduced by both AAVs, the full length gene...SpCas9 which had modest editing rates in HEK-293T cells when compared to the full-length SpCas9. In 2016... allows cleavage of HBB and CCR5 genes in human cells using compact expression cassettes. Sci Rep 5: ....indel formation and phenotypic changes as early as 1 week post-injection. Livers from these mice were histologically...

...activity in cells (Jiang & Doudna, 2017). Within an interior cavity, Cas9 grips nucleotides 1-10 of the ...Guide RNA and Target DNA. Cell, 156(5), 935–949. https://doi.org/10.1016/j.cell.2014.02.001 Osuka, S., Isomura... basic parts of the Cas9 enzyme.   Figure 1: A cartoon depiction of Cas9’s two major lobes, REC...the CRISPR system (Nishimasu et al., 2014). Table 1. Summary of Cas9 domains, the lobe each domain belongs...state (PDB ID 4CMP) with domains colored as in Figure 1. HNH, red; RuvC, orange; CTD, yellow; REC lobe, light... on itself at the bottom of the image. Stem loops 1 and 2 extend horizontally across both lobes. The guide...outside of the protein, spanning both lobes. Stem loop 1, nestled between the REC and CTD domains, is required...