Systems-wide analysis of ubiquitylation dynamics reveals a key role for PAF15 ubiquitylation in DNA-damage bypass

TY - JOUR

T1 - Systems-wide analysis of ubiquitylation dynamics reveals a key role for PAF15 ubiquitylation in DNA-damage bypass

AU - Povlsen, Lou K

AU - Beli, Petra

AU - Wagner, Sebastian A

AU - Poulsen, Sara L

AU - Sylvestersen, Kathrine B

AU - Poulsen, Jon Wriedt

AU - Nielsen, Michael L

AU - Bekker-Jensen, Simon

AU - Mailand, Niels

AU - Choudhary, Chuna Ram

PY - 2012/10

Y1 - 2012/10

N2 - Protein ubiquitylation has emerged as a key regulatory mechanism in DNA-damage signalling and repair pathways. We report a proteome-wide, site-specific survey of ubiquitylation changes after ultraviolet irradiation, identifying numerous upregulated and downregulated ubiquitylation sites on known components of DNA-damage signalling, as well as on proteins not previously implicated in this process. Our results uncover a critical role for PCNA-associated factor PAF15 (p15(PAF)/KIAA0101) ubiquitylation during DNA replication. During unperturbed S phase, chromatin-associated PAF15 is modified by double mono-ubiquitylation of Lys 15 and 24 templated through PCNA binding. Replication blocks trigger rapid, proteasome-dependent removal of Lys 15/24-ubiquitylated PAF15 from PCNA, facilitating bypass of replication-fork-blocking lesions by allowing recruitment of translesion DNA synthesis polymerase polη to mono-ubiquitylated PCNA at stalled replisomes. Our findings demonstrate widespread involvement of ubiquitin signalling in genotoxic-stress responses and identify a critical function for dynamic PAF15 ubiquitylation in safeguarding genome integrity when DNA replication is challenged.

AB - Protein ubiquitylation has emerged as a key regulatory mechanism in DNA-damage signalling and repair pathways. We report a proteome-wide, site-specific survey of ubiquitylation changes after ultraviolet irradiation, identifying numerous upregulated and downregulated ubiquitylation sites on known components of DNA-damage signalling, as well as on proteins not previously implicated in this process. Our results uncover a critical role for PCNA-associated factor PAF15 (p15(PAF)/KIAA0101) ubiquitylation during DNA replication. During unperturbed S phase, chromatin-associated PAF15 is modified by double mono-ubiquitylation of Lys 15 and 24 templated through PCNA binding. Replication blocks trigger rapid, proteasome-dependent removal of Lys 15/24-ubiquitylated PAF15 from PCNA, facilitating bypass of replication-fork-blocking lesions by allowing recruitment of translesion DNA synthesis polymerase polη to mono-ubiquitylated PCNA at stalled replisomes. Our findings demonstrate widespread involvement of ubiquitin signalling in genotoxic-stress responses and identify a critical function for dynamic PAF15 ubiquitylation in safeguarding genome integrity when DNA replication is challenged.

KW - Carrier Proteins

KW - Cell Line

KW - DNA Damage

KW - DNA Repair

KW - DNA Replication

KW - DNA-Directed DNA Polymerase

KW - Humans

KW - Lysine

KW - Proteasome Endopeptidase Complex

KW - S Phase

KW - Signal Transduction

KW - Ubiquitination

KW - Ultraviolet Rays

U2 - 10.1038/ncb2579

DO - 10.1038/ncb2579

M3 - Journal article

C2 - 23000965

SN - 1465-7392

VL - 14

SP - 1089

EP - 1098

JO - Nature Cell Biology

JF - Nature Cell Biology

IS - 10

ER -