TY - JOUR
T1 - Mrc1 and Tof1 promote replication fork progression and recovery independently of Rad53
AU - Tourriere, Helene
AU - Versini, Gwennaëlle
AU - Cordón-Preciado, Violeta
AU - Alabert, Constance
AU - Pasero, Philippe
PY - 2005/9/2
Y1 - 2005/9/2
N2 - The yeast checkpoint factors Mrc1p and Tof1p travel with the replication fork and mediate the activation of the Rad53p kinase in response to a replication stress. We show here that both proteins are required for normal fork progression but play different roles at stalled forks. Tof1p is critical for the activity of the rDNA replication fork barrier (RFB) but plays a minor role in the replication checkpoint. In contrast, Mrc1p is not necessary for RFB activity but is essential to mediate the replication stress response. Interestingly, stalled forks did not collapse in mrc1Δ cells exposed to hydroxyurea (HU) as they do in rad53 mutants. However, forks failed to restart when mrc1Δ cells were released from the block. The critical role of Mrc1p in HU is therefore to promote fork recovery in a Rad53p-independent manner, presumably through the formation of a stable fork-pausing complex.
AB - The yeast checkpoint factors Mrc1p and Tof1p travel with the replication fork and mediate the activation of the Rad53p kinase in response to a replication stress. We show here that both proteins are required for normal fork progression but play different roles at stalled forks. Tof1p is critical for the activity of the rDNA replication fork barrier (RFB) but plays a minor role in the replication checkpoint. In contrast, Mrc1p is not necessary for RFB activity but is essential to mediate the replication stress response. Interestingly, stalled forks did not collapse in mrc1Δ cells exposed to hydroxyurea (HU) as they do in rad53 mutants. However, forks failed to restart when mrc1Δ cells were released from the block. The critical role of Mrc1p in HU is therefore to promote fork recovery in a Rad53p-independent manner, presumably through the formation of a stable fork-pausing complex.
U2 - 10.1016/j.molcel.2005.07.028
DO - 10.1016/j.molcel.2005.07.028
M3 - Article
SN - 1097-2765
VL - 19
SP - 699
EP - 706
JO - Molecular Cell
JF - Molecular Cell
IS - 5
ER -