title: Physical and functional interactions between MutY glycosylase homologue (MYH) and checkpoint proteins Rad9-Rad1-Hus1.
abstract: The MYH (MutY glycosylase homologue) increases replication fidelity by removing adenines or 2-hydroxyadenine misincorporated opposite GO (7,8-dihydro-8-oxo-guanine). The 9-1-1 complex (Rad9, Rad1 and Hus1 heterotrimer complex) has been suggested as a DNA damage sensor. Here, we report that hMYH (human MYH) interacts with hHus1 (human Hus1) and hRad1 (human Rad1), but not with hRad9. In addition, interactions between MYH and the 9-1-1 complex, from both the fission yeast Schizosaccharomyces pombe and human cells, are partially interchangeable. The major Hus1-binding site is localized to residues 295-350 of hMYH and to residues 245-293 of SpMYH (S. pombe MYH). Val315 of hMYH and Ile261 of SpMYH play important roles for their interactions with Hus1. hHus1 protein and the 9-1-1 complex of S. pombe can enhance the glycosylase activity of SpMYH. Moreover, the interaction of hMYH-hHus1 is enhanced following ionizing radiation. A significant fraction of the hMYH nuclear foci co-localizes with hRad9 foci in H2O2-treated cells. These results reveal that the 9-1-1 complex plays a direct role in base excision repair.
authors.affiliation: Department of Biochemistry and Molecular Biology and Greenebaum Cancer Center, School of Medicine, University of Maryland, Baltimore, MD 21201, USA.
authors.forename: Guoli
authors.initials: G
authors.lastname: Shi
authors.forename: Dau-Yin
authors.initials: DY
authors.lastname: Chang
authors.forename: Chih-Chien
authors.initials: CC
authors.lastname: Cheng
authors.forename: Xin
authors.initials: X
authors.lastname: Guan
authors.forename: Ceslovas
authors.initials: C
authors.lastname: Venclovas
authors.forename: A-Lien
authors.initials: AL
authors.lastname: Lu
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000187:drug effects; D000595:Amino Acid Sequence; D001665:Binding Sites / Q000235:genetics; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D045647:DNA Glycosylases / Q000235:genetics / Q000378:metabolism*; D005092:Exonucleases / Q000235:genetics / Q000378:metabolism*; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008969:Molecular Sequence Data; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
chemical_list: D018797:Cell Cycle Proteins; C549605:HUS1 protein, human; C462949:HUS1B protein, human; D011993:Recombinant Fusion Proteins; D029702:Schizosaccharomyces pombe Proteins; C069930:rad9 protein; D006861:Hydrogen Peroxide; D005982:Glutathione Transferase; D005092:Exonucleases; C113574:Rad1 protein, human; D045647:DNA Glycosylases; C061738:mutY adenine glycosylase