Project description:Genome-wide CRISPR-Cas9 knockout screen using TKOv1 sgRNA library was performed in isogenic RBM10-proficient and RBM10-deficient HCC827 cells.
Project description:The emergence of influenza A viruses (IAVs) from zoonotic reservoirs poses a great threat to human health. As seasonal vaccines are ineffective against zoonotic strains, and newly transmitted viruses can quickly acquire drug resistance, there remains a need for host-directed therapeutics against IAVs. Here, we performed a genome-scale CRISPR/Cas9 knockout screen in human lung epithelial cells with a human isolate of an avian H5N1 strain. Several genes involved in sialic acid biosynthesis and related glycosylation pathways were highly enriched post-H5N1 selection, including SLC35A1, a sialic acid transporter essential for IAV receptor expression and thus viral entry. Importantly, we have identified capicua (CIC) as a negative regulator of cell-intrinsic immunity, as loss of CIC resulted in heightened antiviral responses and restricted replication of multiple viruses. Therefore, our study demonstrates that the CRISPR/Cas9 system can be utilized for the discovery of host factors critical for the replication of intracellular pathogens.
Project description:The emergence of influenza A viruses (IAV) from zoonotic reservoirs poses a great threat to human health. As seasonal vaccines are ineffective against zoonotic strains, and newly transmitted viruses can quickly acquire drug resistance, there remains a need for host- directed therapeutics against IAV. Here, we performed a genome-scale CRISPR/Cas9 knockout screen in human lung epithelial cells with a human isolate of an avian H5N1 strain. Several genes involved in sialic acid biosynthesis and related glycosylation pathways were highly enriched post-H5N1 selection, including SLC35A1, a sialic acid transporter essential for IAV receptor expression and thus viral entry. Importantly, we have identified capicua (CIC) as a negative regulator of cell intrinsic immunity, as loss of CIC resulted in heightened antiviral responses and restricted replication of multiple viruses. Therefore, our study demonstrates that the CRISPR/Cas9 system can be utilized for the discovery of host factors critical for the replication of intracellular pathogens.
Project description:To search for host factors regulating Zika virus infection, we performed a genome-wide loss-of-function CRISPR/Cas9 screen in haploid human ESCs. The regulators were identified by the quantification of enrichment of their mutant clones within a pooled loss-of-function library upon Zika virus infection.
Project description:Glioblastoma Multiforme (GBM) is the most common and aggressive primary brain tumor. Despite recent developments in surgery, chemo- and radiotherapy, a currently poor prognosis of GBM patients highlights an urgent need for novel treatment strategies. Our awareness on importance of epigenetic mechanisms for tumor initiation, progression and apoptotic response lead us to investigate epigenetic regulators of GBM survival through a genetic ablation screen. Screen with our custom library EPIDOKOL targeting functional domains of critical chromatin modifier genes, revealed multiple GBM essentiality gene candidates, most importantly ASH2L. Upon ASH2L ablation, we observed induction of apoptosis and cell cycle arrest concomitant with a set of downregulated signature genes. Massive reduction in tumor forming capacity of ASH2L depleted GBM cells as well as high ASH2L expression in GBM patients in comparison to low grade gliomas (LGG) proved essentiality of the gene for glioma cell fitness. Detection of epigenetic factors modulating tumor survival via high throughput, robust and affordable screens such as EPIDOKOL holds great promise to ultimately enable rapid discovery of novel cancer biomarkers and production of effective therapies which will increase life span and dignity of cancer patients.
Project description:Although many host factors important for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have been reported, the mechanisms by which the virus interacts with host cells remain elusive. Here, we identified tripartite motif containing (TRIM) 28, TRIM33, euchromatic histone lysine methyltransferase (EHMT) 1, and EHMT2 as proviral factors involved in SARS-CoV-2 infection by CRISPR-Cas9 screening. Our result suggested that TRIM28 may play a role in viral particle formation and that TRIM33, EHMT1, and EHMT2 may be involved in viral transcription and replication. UNC0642, a compound that specifically inhibits the methyltransferase activity of EHMT1/2, strikingly suppressed SARS-CoV-2 growth in cultured cells and reduced disease severity in a hamster infection model. This study suggests that EHMT1/2 may be a therapeutic target for SARS-CoV-2 infection.
Project description:Mouse embryonic stem cells have been modified with a DNA methylation reporter based on the Sprn promoter system published in Stelzer et al. (Cell, 2015). This reporter allows selection by Hygromycin as well as mScarlet expression. The cells were infected with a Lentiviral genome-wide CRISPR/Cas library resulting in the upregulation of Hygromycin/mScarlet when cells lose global DNA methylation.