A5071394568- DNA Repair Mechanisms
- CRISPR and Genetic Engineering
- Genomics and Chromatin Dynamics
- DNA and Nucleic Acid Chemistry
- Chromosomal and Genetic Variations
- RNA Research and Splicing
- PARP inhibition in cancer therapy
- Cancer therapeutics and mechanisms
- Peptidase Inhibition and Analysis
- RNA Interference and Gene Delivery
- Genetics and Neurodevelopmental Disorders
- RNA and protein synthesis mechanisms
- Microtubule and mitosis dynamics
- Ubiquitin and proteasome pathways
- Neuroscience and Neuropharmacology Research
- Advanced biosensing and bioanalysis techniques
Beckman Research Institute
2019-2024
Cancer Genetics (United States)
2019-2024
City of Hope
2019-2024
Polθ reverse transcribes RNA by undergoing a significant conformational change and promotes RNA-templated DNA repair.
Disrupting either the DNA annealing factor RAD52 or A-family polymerase POLQ can cause synthetic lethality with defects in BRCA1 and BRCA2, which are tumor suppressors important for homology-directed repair of double-strand breaks (DSBs), protection stalled replication forks. A likely mechanism this is that and/or backup pathways DSB stress responses. The features events require vs. POLQ, whether combined disruption these factors causes distinct effects on genome maintenance, have been...
Non-homologous end joining (NHEJ) is the predominant pathway that repairs DNA double-strand breaks in vertebrates. During NHEJ ends are held together by a multi-protein synaptic complex until they ligated. Here, we use Xenopus laevis egg extract to investigate role of intrinsically disordered C-terminal tail XRCC4-like factor (XLF), critical synapsis. We demonstrate XLF along with Ku-binding motif (KBM) at extreme C-terminus required for joining. Although underlying sequence can be varied,...
Repeat-mediated deletions (RMDs) often involve repetitive elements (e.g., short interspersed elements) with sequence divergence that is separated by several kilobase pairs (kbps). We have examined RMDs induced DNA double-strand breaks (DSBs) under varying conditions of repeat (identical versus 1% and 3% divergent) DSB/repeat distance (16 bp-28.4 kbp). find the BLM helicase promotes long distances 28.4 kbp), which consistent a role in extensive DSB end resection, because resection nucleases...
Abstract Canonical non-homologous end joining (C-NHEJ) factors can assemble into a long-range (LR) complex with DNA ends relatively far apart that contains DNAPKcs, XLF, XRCC4, LIG4, and the KU heterodimer short-range (SR) lacking DNAPKcs has positioned for ligation. Since SR form de novo, role of LR (i.e., DNAPKcs) chromosomal EJ is unclear. We have examined blunt double-strand breaks (DSBs), found significantly less important than XLF such EJ. However, weakening via disrupting interaction...
Chromosomal double strand breaks (DSBs) can initiate several signaling events, such as ubiquitination, however the precise influence of on DSB repair outcomes remains poorly understood. With an RNA interference screen, we found that E3 ubiquitin ligase RNF8 suppresses a deletion rearrangement mediated by canonical non-homologous end joining (C-NHEJ). We also EJ without insertion/deletion mutations, which is hallmark C-NHEJ. Conversely, promotes alternative (ALT-EJ) events involving...
Abstract Repeat-mediated deletions (RMDs) are a type of chromosomal rearrangement between two homologous sequences that causes loss the sequence repeats, along with one repeats. Sequence divergence repeats suppresses RMDs; mechanisms such suppression and resolution remains poorly understood. We identified RMD regulators using set reporter assays in mouse cells test key parameters: repeat distances initiating break. found mismatch repair factor MLH1 RMDs same pathway as MSH2 MSH6, which is...
Clastogen exposure can result in chromosomal rearrangements, including large deletions and inversions that are associated with cancer development. To examine such rearrangements human cells, here we developed a reporter assay based on endogenous genes chromosome 12. Using the RNA-guided nuclease Cas9, induced two DNA double-strand breaks, one each
ABSTRACT Repeat-mediated deletions (RMDs) are a type of deletion rearrangement that utilizes two repetitive elements to bridge DNA double-strand break (DSB) leads loss the intervening sequence and one repeats. Sequence divergence between repeats causes RMD suppression indeed this must be resolved in products. The mismatch repair factor, MLH1, was shown critical for both polarity resolution RMDs. Here, we sought study interrelationship these aspects regulation (i.e., polar resolution), by...
A key step of Canonical Nonhomologous End Joining (C-NHEJ) is synapsis DNA double strand break (DSB) ends for ligation. The DNA-PKcs dimer mediates in a long-range complex with DSB remaining apart, whereas the XLF homodimer can mediate both and short-range complexes. Recent structural studies found PAXX may also facilitate complexes via its interactions Ku70. Thus, we examined influence C-NHEJ chromosomal DSBs, which compared to another Ku-binding factor, MRI. Using EJ blunt DSBs Cas9...
Mammalian RAD52 is a DNA repair factor with strand annealing and recombination mediator activities that appear important in both interphase mitotic cells. Nonetheless, dispensable for cell viability. To query synthetic lethal relationships, we performed genome-wide CRISPR knock-out screens identified hundreds of candidate interactions. We then secondary screening genes which depletion causes reduced viability elevated genome instability (increased 53BP1 nuclear foci) RAD52-deficient One such...
Abstract Non-homologous end joining (NHEJ) is the predominant pathway that repairs DNA double strand breaks in vertebrates. During NHEJ ends are held together by a multi-protein synaptic complex until they ligated. Here we investigate role of intrinsically disordered C-terminal tail XLF, critical factor synapsis. We demonstrate XLF along with Ku binding motif (KBM) at extreme C-terminus required for joining. While underlying sequence can be varied, minimal length NHEJ. Single-molecule FRET...
ABSTRACT Repeat-mediated deletions (RMDs) are a type of chromosomal rearrangement between two homologous sequences that causes loss the sequence repeats, along with one repeats. Sequence divergence repeats suppresses RMDs; mechanisms such suppression and resolution mismatched bases remains poorly understood. We identified RMD regulators using set reporter assays in mouse cells test key parameters: repeat distances initiating double-strand break. found mismatch repair factor MLH1 RMDs manner...
The mammalian RAD52 protein is a DNA repair factor that has both strand annealing and recombination mediator activities, yet dispensable for cell viability. To characterize genetic contexts reveal dependence on to sustain viability (i.e., synthetic lethal relationships), we performed genome-wide CRISPR knock-out screens. Subsequent secondary screening found depletion of ERCC6L in RAD52-deficient cells causes reduced elevated genome instability, measured as accumulation 53BP1 into nuclear...
ABSTRACT Canonical non-homologous end joining (C-NHEJ) factors can assemble into a long-range (LR) complex with DNA ends relatively far apart that contains DNAPKcs, XLF, XRCC4, LIG4, and the KU heterodimer short-range (SR) lacking DNAPKcs has positioned for ligation. Since SR form de novo , role of LR (i.e., DNAPKcs) chromosomal EJ is unclear. We have examined blunt double-strand breaks (DSBs), found significantly less important than XLF XRCC4 such EJ. However, weakening via disrupting...