Project description:we performed lentiviral CRISPR interference (CRISPRi) by recruiting dCas9 fused with the KRAB domain to the CSMD1 enhancer (fam3) in the neuronal precursor cell line – Lund human mesencephalic (LUHMES). Given that the expression of CSMD1 was not detectable in LUHMES cells we differentiated these cells into neurons. Differentiated neurons with CRISPRi of CSMD1 enhancer showed significantly higher expression of CSMD1 than control.
Project description:Xist orchestrates X chromosome inactivation, a process that entails chromosome-wide silencing and remodeling of the 3-dimensional structure of the X chromosome. Yet, it remains unclear whether these changes in nuclear structure are mediated by Xist and whether they are required for silencing. Here we show that Xist directly interacts with the Lamin B Receptor (LBR), an integral component of the nuclear lamina, and that this interaction is required for Xist-mediated silencing. We show that this interaction recruits the inactive X to the nuclear lamina and by doing so enables Xist to spread to actively transcribed genes across the X. Our results demonstrate that lamina recruitment changes the accessibility of DNA thereby enabling Xist, and its silencing proteins, to spread across the X to silence transcription. We examined the genomic localization of the Xist lncRNA using RNA Antisense Purification (RAP) in male mouse ES cells where the endogenous Xist promoter is replaced by a tet-inducible one (pSM33) containing 1) wild-type Xist (WT), 2) A-repeat deletion Xist (dA), 3) LBR binding site deletion Xist (dLBS), 4) dLBS-Xist rescued with LMNB1 (LMNB1Res), 5) LBR CRISPRi knock down (LBRKD), or 6) SHARP CRISPRi knock down (SHARPKD).
Project description:We develop a system for bidirectional epigenetic editing (CRISPRai), in which orthogonal activating (CRISPRa) and repressive (CRISPRi) perturbations are applied simultaneously to multiple loci the same cell. We perform ATAC-seq on CRISPRi perturbed Jurkat T cells to investigate chromatin accessibility changes upon perturbation of individual regulatory elements.
Project description:Assess the on- and off-target effects of dox-inducible CRISPR/Cas9 and CRISPRi constructs in a human iPS cell line. Transcript quantification of 3 cell lines, each plus or minus doxycycline and with or without specific single guide RNAs (sgRNAs), with 2 biological replicates each.