Abstract
The MUTYH DNA-glycosylase is indirectly engaged in the repair of the miscoding 7,8-dihydro-8-oxo-20-deoxyguanine (8-oxodG) lesion by removing adenine erroneously incorporated opposite the oxidized purine. Inherited biallelic mutations in the MUTYH gene are responsible for a recessive syndrome, the MUTYH-associated polyposis (MAP), which confers an increased risk of colorectal cancer. In this study, we functionally characterized the Q338H variant using recombinant proteins, as well as cell-based assays. This is a common variant among human colorectal cancer genes, which is generally considered, unrelated to the MAP phenotype but recently indicated as a low-penetrance allele. We demonstrate that the Q338H variant retains a wild-type DNA-glycosylase activity in vitro, but it shows a reduced ability to interact with the replication sensor RAD9:RAD1: HUS1 (9-1-1) complex. In comparison with Mutyh-/- mouse embryo fibroblasts expressing a wild-type MUTYH cDNA, the expression of Q338H variant was associated with increased levels of DNA 8-oxodG, hypersensitivity to oxidant and accumulation of the population in the S phase of the cell cycle. Thus, an inefficient interaction of MUTYH with the 9-1-1 complex leads to a repairdefective phenotype, indicating that a proper communication between MUTYH enzymatic function and the S phase checkpoint is needed for effective repair of oxidative damage.
| Original language | English |
|---|---|
| Pages (from-to) | 4093-4103 |
| Number of pages | 11 |
| Journal | Nucleic Acids Research |
| Volume | 41 |
| Issue number | 7 |
| DOIs | |
| Publication status | Published - Apr 2013 |
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ASJC Scopus subject areas
- Genetics
Cite this
Understanding the role of the Q338H MUTYH variant in oxidative damage repair. / Turco, Eleonora; Ventura, Ilenia; Minoprio, Anna; Russo, Maria Teresa; Torreri, Paola; Degan, Paolo; Molatore, Sara; Ranzani, Guglielmina Nadia; Bignami, Margherita; Mazzei, Filomena.
In: Nucleic Acids Research, Vol. 41, No. 7, 04.2013, p. 4093-4103.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Understanding the role of the Q338H MUTYH variant in oxidative damage repair
AU - Turco, Eleonora
AU - Ventura, Ilenia
AU - Minoprio, Anna
AU - Russo, Maria Teresa
AU - Torreri, Paola
AU - Degan, Paolo
AU - Molatore, Sara
AU - Ranzani, Guglielmina Nadia
AU - Bignami, Margherita
AU - Mazzei, Filomena
PY - 2013/4
Y1 - 2013/4
N2 - The MUTYH DNA-glycosylase is indirectly engaged in the repair of the miscoding 7,8-dihydro-8-oxo-20-deoxyguanine (8-oxodG) lesion by removing adenine erroneously incorporated opposite the oxidized purine. Inherited biallelic mutations in the MUTYH gene are responsible for a recessive syndrome, the MUTYH-associated polyposis (MAP), which confers an increased risk of colorectal cancer. In this study, we functionally characterized the Q338H variant using recombinant proteins, as well as cell-based assays. This is a common variant among human colorectal cancer genes, which is generally considered, unrelated to the MAP phenotype but recently indicated as a low-penetrance allele. We demonstrate that the Q338H variant retains a wild-type DNA-glycosylase activity in vitro, but it shows a reduced ability to interact with the replication sensor RAD9:RAD1: HUS1 (9-1-1) complex. In comparison with Mutyh-/- mouse embryo fibroblasts expressing a wild-type MUTYH cDNA, the expression of Q338H variant was associated with increased levels of DNA 8-oxodG, hypersensitivity to oxidant and accumulation of the population in the S phase of the cell cycle. Thus, an inefficient interaction of MUTYH with the 9-1-1 complex leads to a repairdefective phenotype, indicating that a proper communication between MUTYH enzymatic function and the S phase checkpoint is needed for effective repair of oxidative damage.
AB - The MUTYH DNA-glycosylase is indirectly engaged in the repair of the miscoding 7,8-dihydro-8-oxo-20-deoxyguanine (8-oxodG) lesion by removing adenine erroneously incorporated opposite the oxidized purine. Inherited biallelic mutations in the MUTYH gene are responsible for a recessive syndrome, the MUTYH-associated polyposis (MAP), which confers an increased risk of colorectal cancer. In this study, we functionally characterized the Q338H variant using recombinant proteins, as well as cell-based assays. This is a common variant among human colorectal cancer genes, which is generally considered, unrelated to the MAP phenotype but recently indicated as a low-penetrance allele. We demonstrate that the Q338H variant retains a wild-type DNA-glycosylase activity in vitro, but it shows a reduced ability to interact with the replication sensor RAD9:RAD1: HUS1 (9-1-1) complex. In comparison with Mutyh-/- mouse embryo fibroblasts expressing a wild-type MUTYH cDNA, the expression of Q338H variant was associated with increased levels of DNA 8-oxodG, hypersensitivity to oxidant and accumulation of the population in the S phase of the cell cycle. Thus, an inefficient interaction of MUTYH with the 9-1-1 complex leads to a repairdefective phenotype, indicating that a proper communication between MUTYH enzymatic function and the S phase checkpoint is needed for effective repair of oxidative damage.
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U2 - 10.1093/nar/gkt130
DO - 10.1093/nar/gkt130
M3 - Article
C2 - 23460202
AN - SCOPUS:84876552334
VL - 41
SP - 4093
EP - 4103
JO - Nucleic Acids Research
JF - Nucleic Acids Research
SN - 0305-1048
IS - 7
ER -