Laboratories

Molecular Pharmaco-Biology

KEYWORDS

  • DNA damage tolerance
  • Genome stability control

HEAD

MASUTANI Chikahide

Professor

Researchers

LAB MEMBER

Faculty Position Researchers
MASUDA Yuji Associate Professor Researchers
KANAO Rie Assistant Professor Researchers

CONTACT

Email iga-ryu◎t.mail.nagoya-u.ac.jp (Please send a message after replacing "◎" mark with "@" mark. )

OUTLINE

Our genomic DNA is constantly exposed to damage caused by environmental factors such as ultraviolet radiation, various chemicals, and even byproducts of cellular metabolism. DNA damage interferes with essential processes like transcription and replication, leading to cell death. It can also induce chromosomal abnormalities and mutations, which are major causes of cancer and aging. Cells maintain genome stability through cell cycle checkpoints and DNA repair mechanisms. However, recent studies have highlighted the critical role of an additional system: DNA damage tolerance, which allows cells to overcome replication blocks caused by DNA lesions. Our laboratory focuses on elucidating the molecular mechanisms of DNA damage tolerance in human cells and aims to uncover the comprehensive regulatory network that safeguards genome stability. Through this research, we seek to advance the understanding of cancer and other genome instability-related diseases, as well as aging.

RESEARCH PROJECTS

1. Molecular Mechanisms and Regulation of Translesion DNA Synthesis (TLS)

TLS is the most extensively studied DNA damage tolerance pathway. We identified human DNA polymerase eta (Polη) as the product of the gene responsible for xeroderma pigmentosum variant (XP-V), a cancer-prone genetic disorder. Polη maintains genome stability and prevents carcinogenesis by performing TLS across major UV-induced DNA lesions. To date, several specialized DNA polymerases have been reported to mediate TLS for different types of DNA damage. TLS polymerases, including Polη, are inherently error-prone, acting as a double-edged sword that can also promote genome instability. Our research focuses on the regulation of TLS through PCNA ubiquitination and protein-protein interactions.

2. RFWD3-Mediated DNA Damage Tolerance

Using specific DNA-damaging agents, we revealed a DNA damage tolerance pathway distinct from TLS and identified RFWD3 as a novel factor involved in this mechanism. RFWD3 is one of the gene products responsible for Fanconi anemia, a genome instability disorder. Interestingly, in this context, RFWD3 functions independently of other components of the Fanconi pathway. We are currently investigating the molecular basis of this previously uncharacterized mechanism.

3. DNA Damage Tolerance Targeting Endogenous Lesions

Abasic sites are major endogenous DNA lesions generated by reactive oxygen species. HMCES protein has been reported to covalently bind to abasic sites at replication forks, forming a protein-DNA adduct that contributes to genome stability. However, we discovered that the HMCES-DNA adduct itself strongly inhibits DNA synthesis and cannot be resolved by known TLS pathways. Our research aims to elucidate the mechanism that overcomes replication blocks caused by HMCES-DNA adducts.

4. Fundamental Principles of Ubiquitination

Ubiquitination plays a critical role in regulating various cellular processes, including DNA damage tolerance. We are investigating the fundamental principles underlying ubiquitin-mediated regulation.

5. Identification of Therapeutic Targets

While DNA damage tolerance is essential for maintaining genome stability in normal cells, it also supports cancer cell survival under stress conditions. By elucidating DNA damage tolerance mechanisms, we aim to identify novel targets for anticancer drug development.

BIBLIOGRAPHY

2023
  1. Sugimoto Y, *Masuda Y, Iwai S, Miyake Y, Kanao R, Masutani C. Novel mechanisms for the removal of strong replication-blocking
  2. HMCES- and thiazolidine-DNA adducts in humans. Nucleic Acids Research, 51, 4959-4981. doi:10.1093/nar/gkad246. PMID: 37021581
2022
  1. Kanao R, Kawai H, Taniguchi T, Takata M, and *Masutani C. RFWD3 and translesion DNA polymerases contribute to PCNA modification–dependent DNA damage tolerance. Life Sci Alliance, 5, e202201584. doi: 10.26508/lsa.202201584. PMID: 35905994
  2. Sonohara Y, Takatsuka R, Masutani C, Iwai S, *Kuraoka I. Acetaldehyde induces NER repairable mutagenic DNA lesions. Carcinogenesis, 43, 52-59 doi: 10.1093/carcin/bgab087. PMID: 34546339
2019
  1. *Masuda Y, Saeki Y, Arai N, Kawai H, Kukimoto I, Tanaka K, Masutani C. (2019) Stepwise multipolyubiquitination of p53 by the E6AP-E6 ubiquitin ligase complex. J Biol Chem 294, 14860-14875 doi: 10.1074/jbc.RA119.008374. PMID: 31492752
  2. *Masuda Y, Kanao R, Kawai H, Kukimoto I, Masutani C. (2019) Preferential digestion of PCNA-ubiquitin and p53-ubiquitin linkages by USP7 to remove polyubiquitin chains from substrates. J Biol Chem. 294, 4177-4187. doi: 10.1074/jbc.RA118.005167. PMID:30647135
2018
  1. *Masuda Y, Mitsuyuki S, Kanao R, Hishiki A, Hashimoto H, Masutani C. (2018) Regulation of HLTF-mediated PCNA polyubiquitination by RFC and PCNA monoubiquitination levels determines choice of damage tolerance pathway. Nucleic Acids Res. 46, 11340-11356. doi: 10.1093/nar/gky943. PMID:30335157
2017
  1. Sasatani M, Xi Y, Kajimura J, Kawamura T, Piao J, Masuda Y, Honda H, Kubo K, Mikamoto T, Watanabe H, Xu Y, Kawai H, Shimura T, Noda A, Hamasaki K, Kusunoki Y, Zaharieva E, *Kamiya K. (2017) Overexpression of Rev1 promotes the development of carcinogen-induced intestinal adenomas via accumulation of point mutation and suppression of apoptosis proportionally to the Rev1 expression level. Carcinogenesis 38, 570-578. doi: 10.1093/carcin/bgw208
2015
  1. Kashiwaba S, Kanao R, Masuda Y, Matsuo-Kusumoto R, Hanaoka F, *Masutani C. (2015) USP7 Is a Suppressor of PCNA Ubiquitination and Oxidative-Stress-Induced Mutagenesis in Human Cells. Cell Rep. 13, 2072-2080 doi:10.1016/j.celrep.2015.11.014
  2. Le HP, Masuda Y, Tsurimoto T, Maki S, Katayama T, *Furukohri A, Maki H.Short CCG repeat in huntingtin gene is an obstacle for replicative DNA polymerases, potentially hampering progression of replication fork.Genes Cell 20, 817-33. doi: 10.1111/gtc.12275
  3. Masuda Y, Kanao R, Kaji K, Ohmori H, Hanaoka F, *Masutani C. Different types of interaction between PCNA and PIP boxes contribute to distinct cellular functions of Y-family DNA polymerases. Nucleic Acids Res. 43, 7898-7910. doi: 10.1093/nar/gkv712
  4. Niimi A, Hopkins SR, Downs JA, *Masutani C. The BAH domain of BAF180 is required for PCNA ubiquitination. Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis 779, 16-23, doi:10.1016/j.mrfmmm.2015.06.006
  5. Takahata C, Masuda Y, Takedachi A, Tanaka K, Iwai S, *Kuraoka I. Repair synthesis step involving ERCC1-XPF participates in DNA repair of the Top1-DNA damage complex. Carcinogenesis. pii: bgv078. doi: 10.1093/carcin/bgv078
  6. Kanao R, Yokoi M, Ohkumo T, Sakurai Y, Dotsu K, Kura S, Nakatsu Y, Tsuzuki T, Masutani C, *Hanaoka F. UV-induced mutagenesis in epidermal cells of mice defective in DNA polymerase η and/or ι. DNA Repair 29, 139-146, doi:10.1016/j.dnarep.2015.02.006.
  7. Kanao R, Masuda Y, Deguchi S, Yumoto-Sugimoto M, Hanaoka F, *Masutani C. Relevance of Simultaneous Mono-Ubiquitinations of Multiple Units of PCNA Homo-Trimers in DNA Damage Tolerance. PLoS One 10, e0118775. doi: 10.1371/journal.pone.0118775.
2014
  1. Kamath-Loeb AS, Balakrishna S, Whittington D, Shen JC, Emond MJ, Okabe T, Masutani C, Hanaoka F, Nishimura S, *Loeb LA. Sphingosine: a modulator of human translesion DNA polymerase activity. J. Biol. Chem.289, 21663-21672, doi: 10.1074/jbc.M114.57024
  2. Cao L, *Kawai H, Sasatani M, Iizuka D, Masuda Y, Inaba T, Suzuki K, Ootsuyama A, Umata T, Kamiya K, Suzuki F: A novel ATM/TP53/p21-mediated checkpoint only activated by chronic γ -irradiation. PLoS ONE 9: e104279, 2014.
  3. Shibutani T, *Ito S, Toda M, Kanao R, Collins LB, Shibata M, Urabe M, Koseki H, Masuda Y, Swenberg JA, Masutani C, Hanaoka F, Iwai S, *Kuraoka I. Guanine- 5-carboxylcytosine base pairs mimic mismatches during DNA replication. Sci. Rep. 4, 5220, doi: 10.1038/srep05220.
  4. Yamamoto J, Oyama T, Kunishi T, Masutani C, Hanaoka F, *Iwai S. A cyclobutane thymine-N4-methylcytosine dimer is resistant to hydrolysis but strongly blocks DNA synthesis. Nucleic Acids Res. 42, 2075-2084
2013
  1. Arichi N, Yamamot J, Takahata C, Sano E, Masuda Y, Kuraoka I, *Iwai S. (2013) Strand breakage of a (6-4) photoproduct-containing DNA at neutral pH and its repair by the ERCC1-XPF protein complex. Org. Biomol. Chem. 11, 3526-3534
  2. Tomida J, Itaya A, Shigechi T, Unno J, Uchida E, Ikura M, Masuda Y, Matsuda S, Adachi J, Kobayashi M, Meetei AR, Maehara Y, Yamamoto KI, Kamiya K, Matsuura A, Matsuda T, Ikura T, Ishiai M, *Takata M. (2013) A novel interplay between the Fanconi anemia core complex and ATR-ATRIP kinase during DNA cross-link repair. Nucleic Acids Res. 41, 6930-6941
2012
  1. *Masuda Y, Suzuki M, Kawai H, Hishiki A, Hashimoto H, Masutani C, Hishida T, Suzuki F, Kamiya K. (2012) En bloc transfer of poly-ubiquitin chains to PCNA in vitro is mediated by two human E2-E3 pairs. Nucleic. Acids Res. 40, 10394-10407
  2. *Masuda Y, Suzuki M, Kawai H, Suzuki, F, Kamiya, K. (2012) Asymmetric nature of two subunits of RAD18, a RING-type ubiquitin ligase E3, in the human RAD6A–RAD18 ternary complex. Nucleic Acids Res. 40, 1065-1076
2011
  1. Yanagihara H, Kobayashi J, Tateishi S, Kato A, Matsuura S, Tauchi H, Yamada K, Takwzawa J, Sugasawa K, Masutani C, Hanaoka F, Weemaes CM, Mori T, Zou L, *Komatsu K. (2011) NBS1 recruits RAD18 via a RAD6-like domain and regulates Polη-dependent translesion DNA synthesis. Mol. Cell 43, 788-797
  2. Pozo FM, Oda T, Sekimoto T, Murakumo Y, Masutani C, Hanaoka F, *Yamashita T. (2011) Molecular Chaperone Hsp90 Regulates REV1-Mediated Mutagenesis. Mol. Cell. Biol. 31, 3396-3409
  3. Yamamoto J, Nishiguchi K, Manabe K, Masutani C, Hanaoka F, *Iwai S. (2011) Photosensitized [2 + 2] cycloaddition of N-acetylated cytosine affords stereoselective formation of cyclobutane pyrimidine dimer. Nucleic Acids Res. 39, 1165-1175
2010
  1. Hirota K, Sonoda E, Kawamoto T, Motegi A, Masutani C, Hanaoka F, Szüts D, Iwai S, Sale JE, Lehmann A, *Takeda S. (2010) Simultaneous disruption of two DNA polymerases, Polη and Polζ, in avian DT40 cells unmasks the role of Polη in cellular response to various DNA lesions. PLoS Genetics 6, pii: e1001151
  2. Kashiwagi S, Kuraoka I, Fujiwara Y, Hitomi K, Cheng QJ, Fuss JO, Shin DS, Masutani C, Tainer JA, Hanaoka F, *Iwai S. (2010) Characterization of a Y-family DNA polymerase eta from the eukaryotic themophile Alvinella pompejana. J. Nucleic Acids 2010, pii: 701472
  3. Biertümpfel C, Zhao Y, Kondo Y, Ramón-Maiques S, Gregory M, Lee JY, Masutani C, Lehmann AR, *Hanaoka F, *Yang W. (2010) Structure and mechanism of human DNA polymerase η. Nature 46, 1044-1048
  4. Sekimoto T, Oda T, Pozo FM, Murakumo Y, Masutani C, Hanaoka F, *Yamashita T. (2010) The molecular chaperone Hsp90 regulates accumulation of DNA polymerase η at replication stalling sites in UV-irradiated cells. Mol. Cell 37, 79-89
  5. Chijiwa S, Masutani C, Hanaoka F, Iwai S, *Kuraoka I. (2010) Polymerization by DNA polymerase η is blocked by cis-diamminedichloroplatinum(II) 1,3-d(GpTpG) crosslink: Implications for cytotoxic effects in nucleotide excision repair-negative tumor cells. Carcinogenesis 31, 388-393
  6. Katafuchi A, Sassa A, Niimi N, Gruz P, Fujimoto H, Masutani C, Hanaoka F, Ohta T, *Nohmi T. (2010) Critical amino acids involved in erroneous incorporation of oxidized nucleotides by human DNA polymerase η and κ. Nucleic Acids Res. 38, 859-867

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