The ERCC1/XPF endonuclease is required for efficient single-strand annealing and gene conversion in mammalian cells

• The mammalian ERCC1-XPF endonuclease has a suggested role in the repair of DNA double-strand breaks (DSB) by single-strand annealing (SSA). Here, we investigated the role of ERCC1 in homologous recombination in mammalian cells, and confirm a role of ERCC1 in SSA. Interestingly, we also report an unexpected role for ERCC1 in gene conversion. This provides support that gene conversion in mammalian somatic cells is carried out through synthesis-dependent strand annealing, rather than through a double Holliday Junction mechanism. Moreover, we find low frequencies of SSA and gene conversion in G1-arrested cells, suggesting that SSA is not a frequent DSB repair pathway in G1-arrested mammalian cells, even in the presence of perfect repeats. Furthermore, we find that SSA is not influenced by inhibition of CDK2 (using Roscovitine), ATM (using Caffeine and KU55933), Chk1 (using CEP-3891) or DNA-PK (using NU7026).

Ämnesord

NATURVETENSKAP  -- Biologi -- Biokemi och molekylärbiologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Biochemistry and Molecular Biology (hsv//eng)

Nyckelord

nucleotide excision-repair

homologous recombination repair

break repair

dna-repair

nuclear abnormalities

directed repair

cycle

atm

inhibition

pathways

Cell and molecular biology

Cell- och molekylärbiologi

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)