Destruction of Claspin by SCFbetaTrCP restrains Chk1 activation and facilitates recovery from genotoxic stress

TY - JOUR

T1 - Destruction of Claspin by SCFbetaTrCP restrains Chk1 activation and facilitates recovery from genotoxic stress

AU - Mailand, Niels

AU - Bekker-Jensen, Simon

AU - Bartek, Jiri

AU - Lukas, Jiri

PY - 2006

Y1 - 2006

N2 - We show that Claspin, an adaptor protein required for Chk1 activation, becomes degraded at the onset of mitosis. Claspin degradation was triggered by its interaction with, and ubiquitylation by, the SCFbetaTrCP ubiquitin ligase. This interaction was phosphorylation dependent and required the activity of the Plk1 kinase and the integrity of a betaTrCP recognition motif (phosphodegron) in the N terminus of Claspin. Uncoupling of Claspin from betaTrCP by mutating the conserved serines in Claspin's phosphodegron or by knocking down betaTrCP stabilized Claspin in mitosis, impaired Chk1 dephosphorylation, and delayed G2/M transition during recovery from cell cycle arrest imposed by DNA damage or replication stress. Moreover, the inability to degrade Claspin allowed partial reactivation of Chk1 in cells exposed to DNA damage after passing the G2/M transition. Our data suggest that degradation of Claspin facilitates timely reversal of the checkpoint response and delineates the period permissive for Chk1 activation during cell cycle progression.

AB - We show that Claspin, an adaptor protein required for Chk1 activation, becomes degraded at the onset of mitosis. Claspin degradation was triggered by its interaction with, and ubiquitylation by, the SCFbetaTrCP ubiquitin ligase. This interaction was phosphorylation dependent and required the activity of the Plk1 kinase and the integrity of a betaTrCP recognition motif (phosphodegron) in the N terminus of Claspin. Uncoupling of Claspin from betaTrCP by mutating the conserved serines in Claspin's phosphodegron or by knocking down betaTrCP stabilized Claspin in mitosis, impaired Chk1 dephosphorylation, and delayed G2/M transition during recovery from cell cycle arrest imposed by DNA damage or replication stress. Moreover, the inability to degrade Claspin allowed partial reactivation of Chk1 in cells exposed to DNA damage after passing the G2/M transition. Our data suggest that degradation of Claspin facilitates timely reversal of the checkpoint response and delineates the period permissive for Chk1 activation during cell cycle progression.

KW - Adaptor Proteins, Signal Transducing

KW - Amino Acid Sequence

KW - Binding Sites

KW - Cell Cycle

KW - Cell Cycle Proteins

KW - Cell Line

KW - Cell Line, Tumor

KW - Cells, Cultured

KW - Cyclin A

KW - DNA Damage

KW - Doxorubicin

KW - Fibroblasts

KW - Humans

KW - Models, Biological

KW - Molecular Sequence Data

KW - Mutation

KW - Nuclear Proteins

KW - Phosphorylation

KW - Protein Kinases

KW - Protein-Tyrosine Kinases

KW - RNA, Small Interfering

KW - SKP Cullin F-Box Protein Ligases

KW - Sequence Homology, Amino Acid

KW - Transfection

KW - Ubiquitin

U2 - 10.1016/j.molcel.2006.06.016

DO - 10.1016/j.molcel.2006.06.016

M3 - Journal article

C2 - 16885021

SN - 1097-2765

VL - 23

SP - 307

EP - 318

JO - Molecular Cell

JF - Molecular Cell

IS - 3

ER -