October 9 - 12, 2012
Building 10 & Natcher Conference Center
- General Schedule of Events
- Opening Plenary Session
- Concurrent Symposia Sessions
- Poster Sessions
- National Graduate Student Research Conference
- FARE Award Ceremony
- Special Exhibits on Resources for Intramural Research
- TSA Research Festival Exhibit Show
- Clinical Center Tours
- Research Festival Committees
- Past Research Festivals
Identification of early replicating fragile sites that contribute to genome instability
| Friday, November 08, 2013 — Poster Session IV | |||
|---|---|---|---|
2:00 p.m. – 4:00 p.m. |
FAES Academic Center (Upper-Level Terrace) |
NCI |
COMPBIO-3 |
Authors
- R.B. Faryabi
- J.H. Barlow
- E. Callen
- R. Casellas
- L. Staudt
- O. Fernandez-Capetillo
- A. Nussenzweig
Abstract
DNA double strand breaks (DSBs) in B lymphocytes arise stochastically during replication or as a result of targeted DNA damage by activation induced cytidine deaminase (AID). Here we identify recurrent, early replicating and AID independent DNA lesions, termed early replication fragile sites (ERFS), by genome-wide localization of DNA repair proteins in B cells subjected to replication stress. ERFS colocalize with highly expressed gene clusters and are enriched for repetitive elements and CpG dinucleotides. Although distinct from late-replicating common fragile sites (CFS), the stability of ERFSs and CFSs is similarly dependent on the replication-stress response kinase ATR. ERFSs break spontaneously during replication, but their fragility is increased by hydroxyurea, ATR inhibition or deregulated c-Myc expression. Moreover, greater than 50% of recurrent amplifications/deletions in human diffuse large B cell lymphoma map to ERFSs. In summary, we have identified a source of spontaneous DNA lesions that drives instability at preferred genomic sites.
