1. Human DNA helicase B (HDHB) binds to replication protein A and facilitates cellular recovery from replication stress
- Author
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Hanjian Liu, Gulfem D. Guler, Walter J. Chazin, Diana R. Arnett, Elisabeth Kremmer, Ellen Fanning, and Sivaraja Vaithiyalingam
- Subjects
DNA Replication ,Protein Folding ,DNA damage ,Protein subunit ,Molecular Sequence Data ,DNA and Chromosomes ,Biochemistry ,Chromosomes ,Protein–protein interaction ,Stress, Physiological ,Replication Protein A ,Humans ,Protein Interaction Domains and Motifs ,Amino Acid Sequence ,Single-strandes-DNA ,Dependent adenosine-triophosphatase ,Polymerase alpha-primase ,Mouse FM3A cells ,Homologous ,Recombination ,Saccharomyces-cerevisiae ,Genome integrity ,Damage response ,Terminal domain ,T-antigen ,Molecular Biology ,Replication protein A ,Osteosarcoma ,biology ,Mutagenesis ,DNA replication ,DNA Helicases ,Helicase ,Cell Biology ,HCT116 Cells ,Molecular biology ,Chromatin ,S Phase Cell Cycle Checkpoints ,biology.protein ,Mutagenesis, Site-Directed ,DNA Damage ,HeLa Cells - Abstract
Maintenance of genomic stability in proliferating cells depends on a network of proteins that coordinate chromosomal replication with DNA damage responses. Human DNA helicase B (HELB or HDHB) has been implicated in chromosomal replication, but its role in this coordinated network remains undefined. Here we report that cellular exposure to UV irradiation, camptothecin, or hydroxyurea induces accumulation of HDHB on chromatin in a dose- and time-dependent manner, preferentially in S phase cells. Replication stress-induced recruitment of HDHB to chromatin is independent of checkpoint signaling but correlates with the level of replication protein A (RPA) recruited to chromatin. We show using purified proteins that HDHB physically interacts with the N-terminal domain of the RPA 70-kDa subunit (RPA70N). NMR spectroscopy and site-directed mutagenesis reveal that HDHB docks on the same RPA70N surface that recruits S phase checkpoint signaling proteins to chromatin. Consistent with this pattern of recruitment, cells depleted of HDHB display reduced recovery from replication stress.
- Published
- 2012