Research output: Contribution to Journal/Magazine › Review article › peer-review
Research output: Contribution to Journal/Magazine › Review article › peer-review
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TY - JOUR
T1 - Cellularly active N-hydroxyurea FEN1 inhibitors block substrate entry to the active site
AU - Exell, Jack C.
AU - Thompson, Mark J.
AU - Finger, L. David
AU - Shaw, Steven J.
AU - Debreczeni, Judit
AU - Ward, Thomas A.
AU - McWhirter, Claire
AU - Siöberg, Catrine L.B.
AU - Molina, Daniel Martinez
AU - Abbott, W. Mark
AU - Jones, Clifford D.
AU - Nissink, J. Willem M.
AU - Durant, Stephen T.
AU - Grasby, Jane A.
PY - 2016/10
Y1 - 2016/10
N2 - The structure-specific nuclease human flap endonuclease-1 (hFEN1) plays a key role in DNA replication and repair and may be of interest as an oncology target. We present the crystal structure of inhibitor-bound hFEN1, which shows a cyclic N-hydroxyurea bound in the active site coordinated to two magnesium ions. Three such compounds had similar IC 50 values but differed subtly in mode of action. One had comparable affinity for protein and protein-substrate complex and prevented reaction by binding to active site catalytic metal ions, blocking the necessary unpairing of substrate DNA. Other compounds were more competitive with substrate. Cellular thermal shift data showed that both inhibitor types engaged with hFEN1 in cells, and activation of the DNA damage response was evident upon treatment with inhibitors. However, cellular EC 50 values were significantly higher than in vitro inhibition constants, and the implications of this for exploitation of hFEN1 as a drug target are discussed.
AB - The structure-specific nuclease human flap endonuclease-1 (hFEN1) plays a key role in DNA replication and repair and may be of interest as an oncology target. We present the crystal structure of inhibitor-bound hFEN1, which shows a cyclic N-hydroxyurea bound in the active site coordinated to two magnesium ions. Three such compounds had similar IC 50 values but differed subtly in mode of action. One had comparable affinity for protein and protein-substrate complex and prevented reaction by binding to active site catalytic metal ions, blocking the necessary unpairing of substrate DNA. Other compounds were more competitive with substrate. Cellular thermal shift data showed that both inhibitor types engaged with hFEN1 in cells, and activation of the DNA damage response was evident upon treatment with inhibitors. However, cellular EC 50 values were significantly higher than in vitro inhibition constants, and the implications of this for exploitation of hFEN1 as a drug target are discussed.
U2 - 10.1038/nchembio.2148
DO - 10.1038/nchembio.2148
M3 - Review article
C2 - 27526030
AN - SCOPUS:84982162361
VL - 12
SP - 815
EP - 821
JO - Nature Chemical Biology
JF - Nature Chemical Biology
SN - 1552-4450
IS - 10
ER -