The crucial role of single-stranded DNA binding in enhancing sensitivity to DNA-damaging agents for Schlafen 11 and Schlafen 13
Kohei Fujiwara,
Masashi Maekawa,
Yuki Iimori,
Akane Ogawa,
Takeshi Urano,
Nobuaki Kono,
Hiroyuki Takeda,
Shigeki Higashiyama,
Makoto Arita,
Junko Murai
Affiliations
Kohei Fujiwara
Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Minato-Ku, Tokyo 105-8512, Japan; Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0052, Japan; Laboratory for Metabolomics, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa 230-0045, Japan
Masashi Maekawa
Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Minato-Ku, Tokyo 105-8512, Japan
Yuki Iimori
Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0052, Japan
Akane Ogawa
Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0052, Japan
Takeshi Urano
Department of Biochemistry, Faculty of Medicine, Shimane University, Izumo, Shimane 693-8501, Japan; Center for Vaccines and Therapeutic Antibodies for Emerging Infectious Diseases, Shimane University, Izumo, Shimane 693-8501, Japan
Nobuaki Kono
Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0052, Japan; Systems Biology Program, Graduate School of Media and Governance, Keio University, Fujisawa, Kanagawa 252-0882, Japan
Hiroyuki Takeda
Division of Proteo-Drug-Discovery, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan
Shigeki Higashiyama
Division of Cell Growth and Tumor Regulation, Proteo-Science Center, Ehime University, Toon, Ehime 791-0295, Japan; Department of Biochemistry and Molecular Genetics, Ehime University Graduate School of Medicine, Toon, Ehime 791-0295, Japan; Department of Oncogenesis and Tumor Regulation, Osaka International Cancer Institute, Chuo-Ku, Osaka 541-8567, Japan
Makoto Arita
Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Minato-Ku, Tokyo 105-8512, Japan; Laboratory for Metabolomics, RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa 230-0045, Japan; Human Biology-Microbiome-Quantum Research Center (WPI-Bio2Q), Keio University, Tokyo, Japan; Cellular and Molecular Epigenetics Laboratory, Graduate School of Medical Life Science, Yokohama City University, Yokohama, Kanagawa 230-0045, Japan
Junko Murai
Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata 997-0052, Japan; Division of Cell Growth and Tumor Regulation, Proteo-Science Center, Ehime University, Toon, Ehime 791-0295, Japan; Department of Biochemistry and Molecular Genetics, Ehime University Graduate School of Medicine, Toon, Ehime 791-0295, Japan; Corresponding author
Summary: Schlafen (SLFN) 11 enhances cellular sensitivity to various DNA-damaging anticancer agents. Among the human SLFNs (SLFN5/11/12/13/14), SLFN11 is unique in its drug sensitivity and ability to block replication under DNA damage. In biochemical analysis, SLFN11 binds single-stranded DNA (ssDNA), and this binding is enhanced by the dephosphorylation of SLFN11. In this study, human cell-based assays demonstrated that a point mutation at the ssDNA-binding site of SLFN11 or a constitutive phosphorylation mutant abolished SLFN11-dependent drug sensitivity. Additionally, we discovered that nuclear SLFN13 with a point mutation mimicking the DNA-binding site of SLFN11 was recruited to chromatin, blocked replication, and enhanced drug sensitivity. Through generating multiple mutants and structure analyses of SLFN11 and SLFN13, we identified protein phosphatase 2A as a binding partner of SLFN11 and the putative binding motif in SLFN11. These findings provide crucial insights into the unique characteristics of SLFN11, contributing to a better understanding of its mechanisms.
