Whether or not metazoan replication initiates at random or specific but flexible sites is an unsolved question. The lack of sequence specificity in origin recognition complex (ORC) DNA binding complicates genome-scale chromatin immunoprecipitation (ChIP)-based studies. Epstein-Barr virus (EBV) persists as chromatinized minichromosomes that are replicated by the host replication machinery. We used EBV to investigate the link between zones of pre-replication complex (pre-RC) assembly, replication initiation, and micrococcal nuclease (MNase) sensitivity at different cell cycle stages in a genome-wide fashion. The dyad symmetry element (DS) of EBV's latent origin, a well-established and very efficient pre-RC assembly region, served as an internal control. We identified 64 pre-RC zones that correlate spatially with 57 short nascent strand (SNS) zones. MNase experiments revealed that pre-RC and SNS zones were linked to regions of increased MNase sensitivity, which is a marker of origin strength. Interestingly, although spatially correlated, pre-RC and SNS zones were characterized by different features. We propose that pre-RCs are formed at flexible but distinct sites, from which only a few are activated per single genome and cell cycle.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3514025 | PMC |
http://dx.doi.org/10.1083/jcb.201109105 | DOI Listing |
Elife
April 2024
Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, United States.
Based on experimentally determined average inter-origin distances of ~100 kb, DNA replication initiates from ~50,000 origins on human chromosomes in each cell cycle. The origins are believed to be specified by binding of factors like the origin recognition complex (ORC) or CTCF or other features like G-quadruplexes. We have performed an integrative analysis of 113 genome-wide human origin profiles (from five different techniques) and five ORC-binding profiles to critically evaluate whether the most reproducible origins are specified by these features.
View Article and Find Full Text PDFBased on experimentally determined average inter-origin distances of ∼100 kb, DNA replication initiates from ∼50,000 origins on human chromosomes in each cell cycle. The origins are believed to be specified by binding of factors like the Origin Recognition Complex (ORC) or CTCF or other features like G-quadruplexes. We have performed an integrative analysis of 113 genome-wide human origin profiles (from five different techniques) and 5 ORC-binding profiles to critically evaluate whether the most reproducible origins are specified by these features.
View Article and Find Full Text PDFClimate extremes, such as heat waves, droughts, extreme rainfall can lead to harvest failures, flooding and consequently threaten the food security worldwide. Improving our understanding about climate extremes can mitigate the worst impacts of climate change and extremes. The objective here is to investigate the changes in climate and climate extremes by considering two time slices (i.
View Article and Find Full Text PDFVasa
November 2021
Department of Internal Medicine, Vascular Center, SRH Klinikum Karlsbad-Langensteinbach, Karlsbad, Germany.
Standard nitinol stents (SNS), with or without drug eluting technology, are an essential tool within the interventional armamentarium in the treatment of patients with peripheral arterial disease. However, they are plagued by a number of limitations: a.) stent fractures, although observed predominately in first-generation stents, do still occur in state-of-the art stent platforms, b.
View Article and Find Full Text PDFAnat Cell Biol
June 2020
Department of Anatomy, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
Iatrogenic injury to subcutaneous nerves on the dorsum of the foot is an established risk factor during the surgical procedures resulting in postoperative pain, sensation loss and painful neuroma. Previous studies have reported on the distribution pattern of the superficial peroneal, deep peroneal and sural nerves (SNs) and their branches with various classifications about specific populations. The purpose of the present study was to evaluate the distribution pattern and classification of the nerves on the dorsum of the foot and analyze the location of these nerves into five zones with clinical implications.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!