Project description:Saccharomyces cerevisiae encodes two distinct Pif1-family helicases – Pif1 and Rrm3 – which have been reported to play distinct roles in numerous nuclear processes. Here, we systematically characterize the roles of Pif1 helicases in replisome progression and lagging- strand synthesis in S. cerevisiae. We demonstrate that either Pif1 or Rrm3 redundantly stimulate strand-displacement by DNA polymerase δ during lagging-strand synthesis. By analyzing replisome mobility in pif1 and rrm3 mutants, we show that Rrm3, with a partially redundant contribution from Pif1, suppresses widespread terminal arrest of the replisome at tRNA genes. Although both head-on and codirectional collisions induce replication fork arrest at tRNA genes, head-on collisions arrest a higher proportion of replisomes; consistent with this observation, we find that head-on collisions between tRNA transcription and replisome progression are under-represented in the S. cerevisiae genome. Further, we demonstrate that tRNA-mediated arrest is R-loop independent, and propose that replisome arrest and DNA damage are mechanistically separable.
Project description:These ChIP-exo data were used to validate the predictions from our live-cell single-molecule imaging experiment The ChIP-exo mapping of ultra-fine localization of endogenous Sox2, halo-Sox2, and two halo-Sox2 mutants (halo-Sox2M and halo-Sox2D) in embryonic stem cells.
Project description:We report the application of single-molecule-based sequencing technology for mapping the Egr2 transcriptional program in developing thymic NKT. We found that Egr2 controls the induction of genes required for NKT development. Examination of developing NKT cells and thymocytes receiving a strong TCR signal in vivo by injecting 500ug anti-TCRb antibody.
Project description:We report the application of single-molecule-based sequencing technology for mapping the Egr2 transcriptional program in developing thymic NKT. We found that Egr2 controls the induction of genes required for NKT development.
Project description:We report the application of single molecule-based sequencing technology for high-throughput genom-wide mapping of MeCP2 binding and DNA methylation in mouse brain and cerebellum respectively. We find a good correlation between MeCP2 occupancy and methyl-CpG density and depletion of MeCP2 binding at CpG Islands, the majority of which are constitutively hypomethylated. This study provides a comprehensive characterisation of the genome wide distribution of MeCP2. Examination of MeCP2 occupancy in mouse brain and the distribution of methylation in mouse cerebellum.
