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Functional significance of the interaction with Ku in DNA double-strand break recognition of XLF.

ABSTRACT: Ku heterodimer is essential for the repair of DNA double-strand breaks (DSBs) by non-homologous end-joining (NHEJ). Ku recruits XLF, also known as Cernunnos, to DSBs. Here we report domain analyses of Ku-XLF interaction. The heterodimeric domain of Ku was found to be sufficient for the recruitment of XLF to DSBs and for the interaction of Ku with XLF. A small C-terminal deletion of XLF completely abolished recruitment of XLF to DSBs and Ku-XLF interaction. This deletion also led to marked reduction of XLF-XRCC4 interaction although the XRCC4-binding site on the XLF N-terminal domain remained intact. These results demonstrate the significance of Ku-XLF interaction in the molecular assembly of NHEJ factors.

SUBMITTER: Yano K

PROVIDER: S-EPMC3066473 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Functional significance of the interaction with Ku in DNA double-strand break recognition of XLF.

Yano Ken-ichi K Morotomi-Yano Keiko K Lee Kyung-Jong KJ Chen David J DJ

FEBS letters 20110222 6

Ku heterodimer is essential for the repair of DNA double-strand breaks (DSBs) by non-homologous end-joining (NHEJ). Ku recruits XLF, also known as Cernunnos, to DSBs. Here we report domain analyses of Ku-XLF interaction. The heterodimeric domain of Ku was found to be sufficient for the recruitment of XLF to DSBs and for the interaction of Ku with XLF. A small C-terminal deletion of XLF completely abolished recruitment of XLF to DSBs and Ku-XLF interaction. This deletion also led to marked reduct ...[more]

PMID: 21349273

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