5 results on '"Britt Adamson"'
Search Results
2. Prime Editing: Precision Genome Editing by Reverse Transcription
- Author
-
Ann Cirincione, Britt Adamson, and Jun Yan
- Subjects
0303 health sciences ,Cell Biology ,Computational biology ,Biology ,Genome ,Reverse transcriptase ,Prime (order theory) ,03 medical and health sciences ,chemistry.chemical_compound ,genomic DNA ,0302 clinical medicine ,chemistry ,Genome editing ,sense organs ,skin and connective tissue diseases ,Molecular Biology ,030217 neurology & neurosurgery ,DNA ,030304 developmental biology ,Sequence (medicine) - Abstract
Genome editing is a method for making targeted sequence changes to the genomes of living cells. Prime editing, recently reported by Anzalone et al. (2019), is a new technology that uses reverse transcription to "write" programmed sequence changes into genomic DNA and thus promises significant technical advances.
- Published
- 2020
3. Enhanced prime editing systems by manipulating cellular determinants of editing outcomes
- Author
-
Peter J. Chen, David R. Liu, Mustafa Sahin, Jeffrey A. Hussmann, Jun Yan, Mark J. Osborn, Gregory A. Newby, Cidi Chen, Purnima Ravisankar, Friederike Knipping, James W. Nelson, Pin-Fang Chen, Jonathan S. Weissman, and Britt Adamson
- Subjects
Silent mutation ,Repair-seq ,Computational biology ,Biology ,Article ,General Biochemistry, Genetics and Molecular Biology ,Prime (order theory) ,mismatch repair ,prime editing ,Genome editing ,Mammalian cell ,genome editing ,CRISPR ,DNA mismatch repair ,CRISPR-Cas9 ,Indel - Abstract
Summary While prime editing enables precise sequence changes in DNA, cellular determinants of prime editing remain poorly understood. Using pooled CRISPRi screens, we discovered that DNA mismatch repair (MMR) impedes prime editing and promotes undesired indel byproducts. We developed PE4 and PE5 prime editing systems in which transient expression of an engineered MMR-inhibiting protein enhances the efficiency of substitution, small insertion, and small deletion prime edits by an average 7.7-fold and 2.0-fold compared to PE2 and PE3 systems, respectively, while improving edit/indel ratios by 3.4-fold in MMR-proficient cell types. Strategic installation of silent mutations near the intended edit can enhance prime editing outcomes by evading MMR. Prime editor protein optimization resulted in a PEmax architecture that enhances editing efficacy by 2.8-fold on average in HeLa cells. These findings enrich our understanding of prime editing and establish prime editing systems that show substantial improvement across 191 edits in seven mammalian cell types., Graphical abstract, Highlights • Pooled CRISPRi screens reveal that MMR inhibits prime editing efficiency and precision • PE4 and PE5 enhance editing outcomes through co-expression of dominant negative MLH1 • Programming additional silent mutations can enhance prime editing by evading MMR • PEmax editor improves prime editing efficacy in synergy with PE4, PE5, and epegRNAs, PE4 and PE5 are efficient and precise prime editing systems developed by leveraging insights into the way DNA repair pathways impact genome editing outcomes
- Published
- 2021
4. Genome-Scale CRISPR-Mediated Control of Gene Repression and Activation
- Author
-
Evan H. Whitehead, Carla P. Guimaraes, Martin Kampmann, Hidde L. Ploegh, Britt Adamson, Barbara Panning, Yuwen Chen, Luke A. Gilbert, Michael C. Bassik, Max A. Horlbeck, Jacqueline E. Villalta, Lei S. Qi, Jonathan S. Weissman, Massachusetts Institute of Technology. Department of Biology, Whitehead Institute for Biomedical Research, and Ploegh, Hidde
- Subjects
Cholera Toxin ,Transcription, Genetic ,1.1 Normal biological development and functioning ,Genomics ,Computational biology ,Biology ,Medical and Health Sciences ,Genome ,General Biochemistry, Genetics and Molecular Biology ,Cell Line ,03 medical and health sciences ,0302 clinical medicine ,Genetic ,Underpinning research ,Genetics ,Epigenome editing ,Humans ,CRISPR ,Diphtheria Toxin ,Gene ,030304 developmental biology ,0303 health sciences ,Gene knockdown ,CRISPR interference ,Biochemistry, Genetics and Molecular Biology(all) ,Genome, Human ,Cas9 ,Human Genome ,Biological Sciences ,Stem Cell Research ,Good Health and Well Being ,Genetic Techniques ,CRISPR-Cas Systems ,Transcription ,030217 neurology & neurosurgery ,Human ,Biotechnology ,Developmental Biology - Abstract
SummaryWhile the catalog of mammalian transcripts and their expression levels in different cell types and disease states is rapidly expanding, our understanding of transcript function lags behind. We present a robust technology enabling systematic investigation of the cellular consequences of repressing or inducing individual transcripts. We identify rules for specific targeting of transcriptional repressors (CRISPRi), typically achieving 90%–99% knockdown with minimal off-target effects, and activators (CRISPRa) to endogenous genes via endonuclease-deficient Cas9. Together they enable modulation of gene expression over a ∼1,000-fold range. Using these rules, we construct genome-scale CRISPRi and CRISPRa libraries, each of which we validate with two pooled screens. Growth-based screens identify essential genes, tumor suppressors, and regulators of differentiation. Screens for sensitivity to a cholera-diphtheria toxin provide broad insights into the mechanisms of pathogen entry, retrotranslocation and toxicity. Our results establish CRISPRi and CRISPRa as powerful tools that provide rich and complementary information for mapping complex pathways.
- Published
- 2014
5. Polyubiquitinated PCNA Recruits the ZRANB3 Translocase to Maintain Genomic Integrity after Replication Stress
- Author
-
Ildiko Hajdu, Sarah A. Petit, David M. Livingston, Yiduo Hu, Stephen C. Kowalczykowski, Amitabh V. Nimonkar, Stephen J. Elledge, Lajos Haracska, Alberto Ciccia, Britt Adamson, Yathish Jagadheesh Achar, John C. Yoon, and Lior Izhar
- Subjects
Replication fork reversal ,DNA replication factor CDT1 ,Replication factor C ,Control of chromosome duplication ,Minichromosome maintenance ,biology.protein ,Origin recognition complex ,Eukaryotic DNA replication ,Cell Biology ,Biology ,Molecular biology ,Molecular Biology ,Replication fork protection - Abstract
Completion of DNA replication after replication stress depends on PCNA, which undergoes monoubiquitination to stimulate direct bypass of DNA lesions by specialized DNA polymerases or is polyubiquitinated to promote recombination-dependent DNA synthesis across DNA lesions by template switching mechanisms. Here we report that the ZRANB3 translocase, a SNF2 family member related to the SIOD disorder SMARCAL1 protein, is recruited by polyubiquitinated PCNA to promote fork restart following replication arrest. ZRANB3 depletion in mammalian cells results in an increased frequency of sister chromatid exchange and DNA damage sensitivity after treatment with agents that cause replication stress. Using in vitro biochemical assays, we show that recombinant ZRANB3 remodels DNA structures mimicking stalled replication forks and disassembles recombination intermediates. We therefore propose that ZRANB3 maintains genomic stability at stalled or collapsed replication forks by facilitating fork restart and limiting inappropriate recombination that could occur during template switching events.
- Published
- 2012
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.