Replication protein A

Replication protein A
Emw · CC BY-SA 4.0 · source
Name	Replication protein A
Organism	Homo sapiens
Length	~352–714 residues (subunits vary)
Subunits	RPA1, RPA2, RPA3

Replication protein A Replication protein A is a heterotrimeric single-stranded DNA-binding complex essential for eukaryotic DNA metabolism. Identified through genetic and biochemical studies in organisms from yeast to humans, it coordinates processes at replication forks and sites of DNA damage. Foundational work by investigators at institutions such as the Cold Spring Harbor Laboratory, the Salk Institute, and the Max Planck Institute connected its function to pathways studied at laboratories including the Whitehead Institute and the Francis Crick Institute.

Structure and subunit composition

The heterotrimer comprises three subunits encoded by genes studied in model organisms including Saccharomyces cerevisiae, Schizosaccharomyces pombe, and humans characterized in projects at the Human Genome Project and the Ensembl consortium. Structural determination efforts at facilities such as the European Molecular Biology Laboratory and synchrotrons at the Advanced Photon Source revealed modular domains related to oligonucleotide/oligosaccharide-binding folds that echo motifs first described in proteins from groups at the University of Cambridge and Massachusetts Institute of Technology. Biophysical analyses by laboratories at the Max Planck Society and the National Institutes of Health showed that the largest subunit interacts with replication factors investigated in studies at the Cold Spring Harbor Laboratory, while the intermediate and small subunits contribute to complex stability characterized by researchers at the Howard Hughes Medical Institute. Evolutionary comparisons published by teams at the European Bioinformatics Institute traced conserved regions across taxa examined at the Smithsonian Institution and the Royal Society.

DNA binding and biochemical properties

Biochemical assays developed in core facilities at the Wellcome Trust and the Gordon and Betty Moore Foundation demonstrated high-affinity single-stranded DNA binding, reported alongside classic enzymology work from the Rockefeller University and kinetic studies at the Max Planck Institute for Biophysical Chemistry. Cooperative binding behavior described in reviews sponsored by the American Society for Biochemistry and Molecular Biology complements footprinting experiments executed at the Salk Institute and binding-site mapping conducted at the European Molecular Biology Organization. Interactions with single-stranded DNA measured by groups at the Cold Spring Harbor Laboratory and the University of California, Berkeley revealed sequence-independent contacts similar to findings in investigations tied to the Howard Hughes Medical Institute and the California Institute of Technology. Assays linking binding dynamics to nucleotide metabolism were advanced in collaborations involving the National Cancer Institute and the Howard Hughes Medical Institute.

Roles in DNA replication

Genetic screens at the MRC Laboratory of Molecular Biology and fork-stabilization studies from the Broad Institute implicated the complex in origin firing and lagging-strand synthesis alongside replisome components characterized at the Johns Hopkins University and the University of Oxford. Coordination with polymerases whose biochemistry was elucidated at the University of Chicago and helicases studied at the Max Planck Institute for Molecular Cell Biology and Genetics places the complex central to replication fork progression described by teams at the St. Jude Children's Research Hospital and the Vanderbilt University Medical Center. Chromatin association dynamics probed at the European Molecular Biology Laboratory and replication timing programs mapped by researchers at the Cold Spring Harbor Laboratory further link the complex to cell-cycle transitions explored at the Salk Institute.

Functions in DNA repair and recombination

Repair pathway roles were delineated in experiments conducted at institutions such as the National Cancer Institute and the Dana-Farber Cancer Institute where the complex was shown to cooperate with factors in nucleotide excision repair characterized at the University of Pennsylvania and homologous recombination proteins studied at the Memorial Sloan Kettering Cancer Center. Interplay with recombination mediators identified in seminal studies at the Whitehead Institute and double-strand break responses analyzed at the Fred Hutchinson Cancer Research Center highlight recruitment to damage sites observed in imaging work at the Broad Institute and live-cell microscopy at the European Molecular Biology Laboratory. Partnerships with checkpoint proteins whose pathways were mapped at the Massachusetts General Hospital and the National Institutes of Health situate the complex within conserved surveillance networks charted by the Howard Hughes Medical Institute.

Regulation and post-translational modifications

Phosphorylation sites were mapped in phosphoproteomics projects at the Proteome Institute and at laboratories affiliated with the Max Planck Society and the European Molecular Biology Laboratory, revealing cell-cycle-dependent modifications first reported by investigators at the University of Cambridge and the Johns Hopkins University. Ubiquitination and SUMOylation described in studies from the University of California, San Francisco and the Scripps Research Institute modulate interactions highlighted in proteomics screens conducted at the Broad Institute and the European Bioinformatics Institute. Regulatory kinase interactions traced to signaling pathways studied at the Rockefeller University and phosphatase activities explored at the University of Oxford underscore dynamic control mechanisms characterized by groups at the Medical Research Council.

Clinical significance and disease associations

Defects in pathways involving the complex have clinical relevance noted in translational studies at the National Cancer Institute and case reports from hospitals including Mayo Clinic and Cleveland Clinic. Altered expression patterns observed in tumor profiling projects run by the Cancer Genome Atlas and therapeutic targeting efforts reported by pharmaceutical teams at Pfizer and Merck & Co. connect the complex to genomic instability phenotypes explored at the Dana-Farber Cancer Institute and Memorial Sloan Kettering Cancer Center. Associations with replication stress syndromes referenced in clinical genetics work at the Wellcome Trust Sanger Institute and patient cohorts assembled at the European Molecular Biology Laboratory indicate relevance to cancer predisposition and potential biomarkers examined by consortia such as the International Cancer Genome Consortium.

Category:DNA-binding proteins