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Showing: 261 - 280 of 780 results
  1. Choosing a CRISPR Nuclease: Site Accessibility, Specificity, and Sensitivity

    Type
    Blog Post
    Published
    Nov. 5, 2019, 1:28 p.m.
    ... Sensitivity Cas9 sensitivity is often closely related to specificity. Sensitivity is a measure of the...site. A specificity ratio can be measured by calculating the on-target activity divided by the off-target... SpCas9 described the PAM specificity of Cas9s isolated from different organisms and engineered Cas9 variants...the enzymes showed decreased off-target activity relative to Cas9. Since then, the Joung and Jennifer Doudna...showed decreased or similar off-target activity, relative to eSpCas9 and SpCas9-HF across a number of different...research due to its small size and specificity relative to Cas9. As scientists continue to characterize...
  2. Sharing is Caring: But How to Distribute Open Hardware?

    Type
    Blog Post
    Published
    Feb. 28, 2023, 2:15 p.m.
    ...devices for research. There are a number of new platforms (such as openUC2, which I am a co-founder of),...that make everyday microscopy much easier. On platforms such as Github, users can download the software...example, can also be printed quickly in Madagascar. Platforms that allow for on-going creativity with the construction...organizations and companies to provide problem-solving platforms.     Fig. 3: Different workflows involved...their work on the shoulders of giants. The still relatively young movement of sharing open hardware has a...Prakash, "Squid: Simplifying Quantitative Imaging Platform Development and Deployment." bioRxiv. 2020. Diederich...
  3. Plasmids 101: Yeast Vectors

    Type
    Blog Post
    Published
    Feb. 25, 2014, 7:11 p.m.
    ...limited to: rapid growth, ease of replica plating and mutant isolation, a well-defined genetic system, and ...and animals. Unlike bacteria, yeast can post-translationally modify proteins yet they still share many of...a previous post, we briefly discussed how the regulation of bacterial ORIs determines plasmid copy number...these vectors can also be controlled if specific regulatable elements are included (reviewed here). Plasmids...complementation is weak. yes   LYS2 L-lysine yes - Grow on plates containing alpha-aminoadipate in the absence of...
  4. Antibodies 101: Designing Your First Flow Panel

    Type
    Blog Post
    Published
    May 28, 2024, 1:45 p.m.
    ...brightness for a few commonly used fluorophores in relation to the laser type. Table adapted from: https:/...are absorbed and then emitted, which creates a relatively stronger — or brighter — signal.   Figure...use brighter fluorophores for markers that are relatively lower in abundance. In contrast, when you expect...the spectra of enhanced GFP (eGFP) and FITC, the latter being a commonly used fluorophore for antibody-...again. In the beginning, we talked about the relationship between a photon's wavelength and energy, how... into different levels of brightness and their relation to the fluorophore's excitation efficiency, and.... His projects include investigating negative regulators of T cells and cytokine signaling in tumor immunity...
  5. Stabilized Bacterial Promoters: Constant Gene Expression at any Copy Number

    Type
    Blog Post
    Published
    Sept. 4, 2018, 12:53 p.m.
    ...Unfortunately, plasmid copy numbers vary within cell populations and over time resulting in variable gene expression... use of stabilized promoters. In contrast to unregulated promoters that are always on, stabilized promoters...expression. However, if you introduce negative regulation by using a promoter that is responsive to a repressor...that the stabilized promoters were able to better modulate gene expression during shifts in growth rate as... as compared to a constitutive promoter. To simulate the increase in plasmid copy number during the transition...generation of the desired product while avoiding the accumulation of toxic intermediates or the shuttling of the...
  6. Seven Tips for Using LinkedIn as a Scientist

    Type
    Blog Post
    Published
    Oct. 1, 2019, 1:21 p.m.
    ...is the question. When presenting on building relationships (also known as “networking”), one of the most...networking to start, build, and track professional relationships. Here are my seven best tips beyond the basics... “Joanne Kamens, PhD viewed your profile.”  The latter is much less creepy. If we’ve met before, I’d be...on LinkedIn!” resulting in just a little more relationship. Pro tip: Once you are connected with someone...connection requests LinkedIn is a place to build relationships. If you don’t add a personal note, you waste...volunteer organizational work. LinkedIn is not the platform for politics, family updates, or click bait of...
  7. To Each HIS Own

    Type
    Blog Post
    Published
    March 2, 2023, 2:15 p.m.
    ...purification. In this strategy a single protein can be isolated from a complex mix using affinity chromatography...variety of methods can be used to successfully isolate proteins, this blog will focus on one of the most...the protein of interest and it is successfully isolated.   Prior to the polyhistidine tag, alternative...binding of untagged proteins. Despite being a relatively low frequency amino acid, proteins containing...questions about polyhistidine tags. For more antibody-related information, sign up to receive alerts for antibody...Purification of Recombinant Proteins with a Novel Metal Chelate Adsorbent. Bio/Technology. 1988; 6: 1321–1325. ...
  8. The Future of Research Symposium Boston 2015

    Type
    Blog Post
    Published
    Oct. 20, 2015, 2:30 p.m.
    ...future prospects. Among the topics discussed, many related to the structure of the biomedical workforce. Quotes...results, not scientists”  These comments are well correlated with published data. For example, in 2010, less...compulsory internship to be taken in an industry, regulatory, or clinical environment. It remains contested...6). Academic data and the labor market for PhDs Later this week, postdocs and students will again gather...grants through the Sloan foundation for postdoc-related data collection and analysis. He is also a strong...training to reflect the workforce." Science Translational Medicine (2015): 285ED4. Pubmed PMID: 25925677...
  9. Plasmids 101: Cre-lox

    Type
    Blog Post
    Published
    Jan. 13, 2015, 3:47 p.m.
    ...have adapted the components for use in genome manipulation. Cre recombinase, originally named because ...because it “causes recombination” (although later referred to as the “cyclization recombinase”), is a 38 kDa... in a DNA sequence allows for very specific manipulations as discussed below. How does it work? As alluded...expression – placing a series of transcriptional and translational termination features with loxP sites on either... can be used to easily perform this eviction. Regulated Cre expression – placing Cre downstream of promoters...express Cre under a variety of ubiquitous and regulated promoters, and many loxP-containing alleles have...
  10. A Look at Addgene's QC Process

    Type
    Blog Post
    Published
    May 6, 2025, 1:15 p.m.
    ...Nobody’s perfect! This is a platitude I’m sure we have all heard. It’s a truth that extends to both people... of tools that rely on DNA amplification and manipulation to produce and edit plasmids. These are prone...polymerases can make mistakes and lead to the accumulation of errors in DNA sequences. In research, these...and identifying mixed plasmid and nucleotide populations. All of these topics require additional considerations...sequence and assemble using the Illumina MiSeq platform, such as GC-rich regions and highly repetitive...Plasmidsaurus for long-read nanopore sequencing. This platform sequences the entire plasmid in one read and thus...
  11. Tips for Technical Support Calls

    Type
    Blog Post
    Published
    Sept. 20, 2016, 2:39 p.m.
    ...calls, I feel compelled to share my years of accumulated wisdom so that you, the customer, can get the...these tips and tricks will apply to any biology-related customer support interaction. Before contacting...paperwork associated with a product only to realize later that everything I could have wanted to know was ... science, but we don’t have the resources to recapitulate the experiments performed by our thousands of...use a particular reagent.  We also have links to later papers that successfully used said plasmids. We ...support scientists wear many hats at this still relatively small nonprofit. If you do go longer than a few...
  12. Viral Vectors 101: Chemogenetics

    Type
    Blog Post
    Published
    July 11, 2023, 1:15 p.m.
    ...field as it provides a noninvasive method for manipulating cell activity, especially neuronal firing. ...approved drugs so that your results are viable for translation to human patients. Picking receptors The receptor...dependent on what cellular response you aim to manipulate. It is important to consider that the same receptor... in. The most common target for chemogenetic manipulation are neurons where chemogenetic receptors can...control ion flux. The system allows you to directly manipulate ion channels. When working with PSAM receptors...BL, Jin J (2015) The First Structure–Activity Relationship Studies for Designer Receptors Exclusively Activated...
  13. A Look Back at One Year of Plasmid Sharing for COVID-19 Research

    Type
    Blog Post
    Published
    July 12, 2021, 1:15 p.m.
    ...received over 13,000 plasmids requests for COVID-19 related plasmids. These plasmids have reached labs in over...expression and pseudotyping efficiency. This plasmid was later used by another team of researchers for neutralization...opportunities to evolve. Several variants are now circulating and plasmids containing these mutations have ...are inhibitors of SARS-CoV-2 entry and become upregulated during viral infection.  Expression of SARS-CoV...their work, head over to their blog post. Months later, we partnered with Ginkgo Bioworks to provide synthesized...screens identify mucins as critical host factors modulating SARS-CoV-2 infection. bioRxiv. https://doi.org...
  14. Reaching out to China: Canton Nucleic Acids Forum (CNAF) 2015

    Type
    Blog Post
    Published
    Dec. 1, 2015, 3:30 p.m.
    ...City The conference was located in the modern, relatively new “Science City” area on the outskirts of Guangzhouon...human tRNA genes and, until now, we've overlooked regulatory fragments of these transcripts. I remember when...have allowed them to begin understanding complex regulation of and by tRNAs and tRNA-derived RNAs. Stay tuned...Medicine presented another unexpected finding in the regulatory RNA field. The Rajewsky lab is studying circular...of Georgia studies the CRISPR/Cas system as it relates to its natural role in prokaryotic immunity to ...against both DNA and RNA viruses - 2 cas systems regulate at the DNA level and 1 at the RNA level. Udi Qimron...
  15. Plasmids 101: Degron Tags

    Type
    Blog Post
    Published
    March 14, 2024, 1:15 p.m.
    ...other systems because the system modulates protein post-translationally, unlike many other methods. Secondly... tags has become increasingly popular for the modulation of endogenously and exogenously expressed proteins...systems. Degron tags are one of many tools to manipulate protein expression. These tags offer several ...Secondly, these tags can be used to manipulate endogenously and exogenously expressed proteins. Thirdly...degradation. Since its first use as a protein regulation tool, AID has gone through an additional round...
  16. Antibodies 101: Conventional vs Spectral Flow Cytometry

    Type
    Blog Post
    Published
    Aug. 3, 2023, 1:15 p.m.
    ...any antibody (positive population) or won’t bind anything (negative population). It is strongly recommended...immunologists, allowing for the rapid analysis of cell populations within a heterogenous tissue type, such as PBMCs...moreso than other methods, the identification and isolation of rare cell types. In recent years, full spectrum...for better resolution of positive and negative populations, Careful panel design In both conventional and...create difficulty when trying to resolve those populations. PE/Cy7 and BB515, on the other hand, have a ...
  17. PCR Applications for Copy Number Variation Assays

    Type
    Blog Post
    Published
    April 26, 2022, 1:15 p.m.
    ...DNA in your sample relative to your normal control - you can set up your calculations so that your assay... one-copy ‘housekeeping’ gene), and quantified relative to a 'normal' sample with known copy number set...nice thing about qPCR is that since it measures relative quantification - that is, since you’re looking...all double-stranded DNA, while Taqman uses an intercalating dye, with a fluorescent probe and quencher to...provides absolute quantitative data, instead of relative quantification.  Even though no one option is ...
  18. Drew Endy Introduces the Biobrick Public Agreement Plasmid Collection

    Type
    Blog Post
    Published
    Dec. 12, 2013, 3:35 p.m.
    ...important to understand that these platforms, or pieces of a platform, that are now available exist within...well-characterized bacterial transcription and translation initiation elements. Open science with BioBricks...replication of DNA, transcription of DNA to make RNA, translation of RNA to make proteins. That's central to everything... transduce otherwise invisible molecules into regulation of gene expression including growth or fluorescence...gene expression via standard transcription and translation initiation." Nature Methods. 10, 354-360 (10 ...
  19. Viral Vectors 101: The Retroviral Lifecycle

    Type
    Blog Post
    Published
    July 27, 2023, 1:15 p.m.
    ...However, retroviral vectors can still direct the translation of proteins because they integrate this reverse-transcribed...then use cell machinery for transcription and translation. Here, we will discuss several aspects of the...The genome of viral tools are often not virology related at all, and you will instead get expression of ... Cullen, B. R. (1992). Mechanism of action of regulatory proteins encoded by complex retroviruses. Microbiological... sarcoma virus: purification of the virus and isolation of the nucleic acid. Proceedings of the National...Initiation of synthesis with 70 S viral RNA as template. Journal of Molecular Biology, 79(1), 163–183....
  20. Course-Based Undergraduate Research Experiences (CUREs)

    Type
    Blog Post
    Published
    Feb. 9, 2023, 2:15 p.m.
    ...more focused format, where all students work on malate dehydrogenase (MDH), a citric acid cycle enzyme...recently purified MDH to study the impact of phosphorylation on the enzyme’s structure, function, and interaction...offering excellent training in improvisation and the latter making him a more effective motivator (“be like...conducting NIH- and NSF-funded research on planarian flatworms both in and out of the classroom.   References...characterization of a fusion protein: Histidine tag, malate dehydrogenase, and green fluorescent protein. Biochemistry...laboratory – a semester-long research approach using malate dehydrogenase as a research model. Biochemistry...
Showing: 261 - 280 of 780 results