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Bae, S.

Publications and source records attributed to Bae, S..

4 recordsLinked to original sources

Web-based design and analysis tools for CRISPR base editing

BackgroundAs a result of its simplicity and high efficiency, the CRISPR-Cas system has been widely used as a genome editing tool. Recently, CRISPR base editors, which consist of deactivated Cas9 (dCas9) or Cas9 nickase (nCas9) linked with a cytidine or a guanine deaminase, have been developed. Base editing tools will be very useful for gene correction because they can produce highly specific DNA substitutions without the introduction of any donor DNA, but dedicated web-based tools to facilitate the use of such tools have not yet been developed.\n\nResultsWe present two web tools for base editors, named BE-Designer and BE-Analyzer. BE-Designer provides all possible base editor target sequences in a given input DNA sequence with useful information including potential off-target sites. BE-Analyzer, a tool for assessing base editing outcomes from next generation sequencing (NGS) data, provides information about mutations in a table and interactive graphs. Furthermore, because the tool runs client-side, large amounts of targeted deep sequencing data (>100MB) do not need to be uploaded to a server, substantially reducing running time and increasing data security. BE-Designer and BE-Analyzer can be freely accessed at http://www.rgenome.net/bedesigner/ and http://www.rgenome.net/be-analyzer/respectively\n\nConclusionWe develop two useful web tools to design target sequence (BE-Designer) and to analyze NGS data from experimental results (BE-Analyzer) for CRISPR base editors.

bioinformatics

Pellino 1 Communicates Intercellular Signaling in Chronic Skin Inflammatory Microenvironment

Chronic skin inflammation including psoriasis is a multisystem disease, affecting more than 5% of the general population. Here we show that Pellino 1 (Peli1), a signal-responsive ubiquitin E3 ligase, is highly up-regulated in human psoriatic skin lesions and that increased Peli1 expression correlates with the immunopathogenesis of psoriasis-like chronic skin inflammatory disease. Interestingly, Peli1 directly interacts with interferon regulatory factor 4 (IRF4, a transcription factor that plays pivotal roles in proliferation and cytokine production) and induces lysine 63-mediated ubiquitination. Peli1-mediated IRF4 ubiquitination appears to be a common systemic signaling mechanism shared by lesional keratinocytes, dendritic cells, macrophages, and T cells, generating a feedback relationship between keratinocyte and Th17 cell responses. Conversely, inhibition of Peli1 interferes with IRF4 induction and attenuates immunopathogenic signaling in the psoriasis. In summary, Peli1-mediated ubiquitination is a common immunopathogenic intercellular signaling in psoriasis-like chronic skin inflammatory microenvironment. Thus, targeting Peli1 could be used as a potential strategy for psoriasis treatment.

immunology

Constructing and visualizing cancer genomic maps in 3D spatial context by phenotype-based high-throughput laser-aided isolation and sequencing (PHLI-seq)

A spatially resolved analysis of the heterogeneous cancer genome, in which the data are connected to the three-dimensional space of a tumour, is crucial to understand cancer biology and the clinical impact of cancer heterogeneity on patients. However, despite recent progress in spatially resolved transcriptomics, spatial mapping of genomic data in a high-throughput and high-resolution manner has been challenging due to current technical limitations. Here, we describe a novel approach, phenotype-based high-throughput laser-aided isolation and sequencing (PHLI-seq), which enables high-throughput isolation of a single-cell or a small number of cells and their genome-wide sequence analysis to construct genomic maps within cancer tissue in relation to the phenotypes of the cells. By applying PHLI-seq, we reveal the heterogeneity of breast cancer tissues at a high resolution and map the genomic landscape of the cells to their corresponding spatial locations and phenotypes in the tumour mass. Additionally, with different staining modalities, the genotypes of the cells can be connected to corresponding phenotypic information of the tissue. Together with the spatially resolved genomic analysis, we can infer the histories of heterogeneous cancer cells in two or three dimensions, providing significant insight into cancer biology and precision medicine.

genomics

Questioning unexpected CRISPR off-target mutations in vivo

To the Editor To the Editor References Recently, Schaefer et al.1 reported that whole genome sequencing (WGS) of two Cas9-treated, gene-corrected mice and a wild-type control mouse unveiled 1,397 single-nucleotide variations (SNVs) and 117 small insertions and deletions (indels) present commonly in the two Cas9-treated mice \"but absent in the uncorrected control\" and from a database of mouse SNVs and indels. There was essentially no sequence homology between the on-target site and these SNVs and indel sites, most of which lacked a protospacer-adjacent motif (PAM) sequence, suggesting that these variations were both small guide RNA (sgRNA)-independent and Cas9-independent, respectively. Nevertheless, the authors made a bold claim that these variations were caused by CRISPR-Cas9 without validating these unexpected off-target effects even at a single SNV or indel site by ...

genomics