Project description:HT29-DKO cells were stably transduced with lentiCas9-Blast (Addgene, #52962) and subsequently selected using Blasticidin. Then, 300 million HT29-DKO cells that constitutively express Cas9 were transduced with lentiGuide-Puro from the Brunello library at MOI 0.3. Cells were then selected with puromycin, expanded to 3 billion cells, and then pooled together and cryofrozen in aliquots. One hundred million cells were thawed constituting over 1000× genome coverage worth of mutagenized library. The cells were infecting with PeV-A1 or PeV-A2 at an MOI of 0.1. Virus-resistant colonies were harvested. The uninfected reference used was the unselected starting population. The unselected and selected cells were both processed with QIAamp DNA columns to purify the gDNA. A first round of PCR was used to amplify the guide RNA sequences encoded in the gDNA, followed by a second round of PCR to add the barcodes/adapters for amplicon sequencing. 2% agarose gels and a QIAquick gel extraction kit were used to purify the amplicons. The amplicons were then subjected to next-generation sequencing on a HiSeq instrument lane (Illumina) via Novogene.
Project description:With the near eradication of poliovirus due to global vaccination campaigns, attention has shifted to other enteroviruses that can cause polio-like paralysis syndrome (now termed acute flaccid myelitis (AFM)). In particular, enterovirus D68 (EV-D68) is believed to be the main driver of epidemic outbreaks of AFM in recent years, yet not much is known about EV-D68 host interactions. EV-D68 is a respiratory virus but, in rare cases, can spread to the central nervous system to cause severe neuropathogenesis. We use genome-scale CRISPR screens to identify genes important for EV-D68 infection. A549 and U87-MG cells were stably transduced with lentiCas9-Blast (Addgene, #52962) and subsequently selected using Blasticidin. Then, 300 million cells that constitutively express Cas9 were transduced with lentiGuide-Puro from the Brunello library (MOI 0.3). Cells were then selected with puromycin, expanded to 3 billion cells, and then pooled together and cryofrozen in aliquots. One hundred million cells were thawed constituting over 1000× genome coverage worth of mutagenized library,expanded, and seeded for the screens. Each screen had over 500x genome coverage. The cells were infected with EV-D68 IL (BEI USA/2014/18952) (MOI 0.1). Virus-resistant colonies were harvested. The uninfected reference used was the unselected starting population. The unselected and selected cells were both processed with QIAamp DNA columns to purify the gDNA. A first round of PCR was used to amplify the guide RNA sequences encoded in the gDNA, followed by a second round of PCR to add the barcodes/adapters for amplicon sequencing. 2% agarose gels and a QIAquick gel extraction kit were used to purify the amplicons. The amplicons were then subjected to next-generation sequencing on a HiSeq instrument lane (Illumina) via Novogene.
Project description:eHAP or U87MG cells were stably transduced with lentiCas9-Blast (Addgene, #52962) and subsequently selected using Blasticidin. Then, 300 million eHAP or U87MG cells that constitutively express Cas9 were transduced with lentiGuide-Puro from the Brunello library at MOI 0.3. Cells were then selected with puromycin, expanded to 3 billion cells, and then pooled together and cryofrozen in aliquots. One hundred million cells were thawed constituting over 1000× genome coverage worth of mutagenized library. Twenty T175 flasks were used for the U87MG-based screen, while twelve T175 flasks were used for the eHAP-based screen. The cells were allowed to recover for 48 hours before infecting with ReoT3D at an MOI of 0.1. Obvious CPE was observed within 72 hours. eHAP-resistant colonies were harvested two weeks later, while U87MG-resistant colonies were harvested six weeks later. The uninfected reference used was the unselected starting population. The unselected and selected cells were both processed with QIAamp DNA columns to purify the gDNA. A first round of PCR was used to amplify the guide RNA sequences encoded in the gDNA, followed by a second round of PCR to add the barcodes/adapters for amplicon sequencing. 2% agarose gels and a QIAquick gel extraction kit were used to purify the amplicons. The amplicons were then subjected to next-generation sequencing on a HiSeq instrument lane (Illumina) via Novogene.
Project description:Unbiased forward genetic screens to identify host factors for DENV1 and JEV in 293FT cells. Unbiased forward genetic screens to identify host factors for HCoV-229E in Huh7.5.1 cells.
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:Huh7.5.1 cells were stably transduced with lentiCas9-Blast (Addgene, #52962) and subsequently selected using Blasticidin. Then, Huh7.5.1 cells that constitutively express Cas9 were transduced with lentiGuide-Puro from the druggable genome library at MOI 0.3. Cells were then selected with puromycin, expanded, and then pooled together and cryofrozen in aliquots. Cells were thawed constituting over 1000× genome coverage worth of mutagenized library. The cells were infecting with DENV2_429557 and DENV-2_16681_Hap1-adapted at MOI of 0.1. Virus-resistant colonies were harvested. The uninfected reference used was the unselected starting population. The unselected and selected cells were both processed with QIAamp DNA columns to purify the gDNA. A first round of PCR was used to amplify the guide RNA sequences encoded in the gDNA, followed by a second round of PCR to add the barcodes/adapters for amplicon sequencing. 2% agarose gels and a QIAquick gel extraction kit were used to purify the amplicons. The amplicons were then subjected to next-generation sequencing on a HiSeq instrument lane (Illumina) via Novogene.
Project description:The goal of these experiments were to test the on-target and target-adjacent editing efficiencies of different single-nucleobase editing systems. Previous studies have shown that tethering DNA mutating enzymes to Cas9-nickase-UGI complexes results in editing of chromosomal DNA. However, these editing events encompass undesirable target-adjacent nucleobase edits. Here, we characterize a novel approach that reduces the frequency of target-adjacent editing while maintaining a high level of on-target editing.
Project description:Genome-wide CRISPR-Cas9 knockout screen using TKOv1 sgRNA library performed in isogenic RBM10-proficient and RBM10-deficient HCC827 cells.
Project description:Increased or decreased B16 cell sensitivity to activated cytotoxic T lymphocytes.To identify tumor cell-intrinsic genes essential for antigen-specific CD8+ T cell killing, we utilized the B16.SIY melanoma cell line which expressed the model antigen SIY (SIYRYYGL) co-expressed with DsRed, that can be recognized by 2C CD8+ TCR transgenic (Tg) T cells. B16.SIY cells were transduced and selected to stably expressed a Cas9 gene, and then transduced with a genome-scale CRISPR gRNA library.Transduced cells were cultured for 8 days to provide time for gene disruption to occur, then were co-cultured with pre-activated 2C CD8+ T cells at a 2:1 Effector:Target ratio for 16 hours. By performing deep sequencing, we examined the sgRNA library representation in tumor cells with or without T cell co-incubation by MAGeCK analysis.