Sequential and Multistep Substrate Interrogation Provides the Scaffold for Specificity in Human Flap Endonuclease 1
KAUST DepartmentBiological and Environmental Sciences and Engineering (BESE) Division
Laboratory of DNA Replication and Recombination
Physical Science and Engineering (PSE) Division
Online Publication Date2013-06-06
Print Publication Date2013-06
Permanent link to this recordhttp://hdl.handle.net/10754/334510
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AbstractHuman flap endonuclease 1 (FEN1), one of the structure-specific 5' nucleases, is integral in replication, repair, and recombination of cellular DNA. The 5' nucleases share significant unifying features yet cleave diverse substrates at similar positions relative to 5' end junctions. Using single-molecule Förster resonance energy transfer, we find a multistep mechanism that verifies all substrate features before inducing the intermediary-DNA bending step that is believed to unify 5' nuclease mechanisms. This is achieved by coordinating threading of the 5' flap of a nick junction into the conserved capped-helical gateway, overseeing the active site, and bending by binding at the base of the junction. We propose that this sequential and multistep substrate recognition process allows different 5' nucleases to recognize different substrates and restrict the induction of DNA bending to the last common step. Such mechanisms would also ensure the protection ofDNA junctions from nonspecific bending and cleavage. 2013 The Authors.
CitationSobhy MA, Joudeh LI, Huang X, Takahashi M, Hamdan SM (2013) Sequential and Multistep Substrate Interrogation Provides the Scaffold for Specificity in Human Flap Endonuclease 1. Cell Reports 3: 1785-1794. doi:10.1016/j.celrep.2013.05.001.
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- Flap endonuclease 1.
- Authors: Balakrishnan L, Bambara RA
- Issue date: 2013
- Single-molecule characterization of Fen1 and Fen1/PCNA complexes acting on flap substrates.
- Authors: Craggs TD, Hutton RD, Brenlla A, White MF, Penedo JC
- Issue date: 2014 Feb
- DNA and Protein Requirements for Substrate Conformational Changes Necessary for Human Flap Endonuclease-1-catalyzed Reaction.
- Authors: Algasaier SI, Exell JC, Bennet IA, Thompson MJ, Gotham VJ, Shaw SJ, Craggs TD, Finger LD, Grasby JA
- Issue date: 2016 Apr 8
- Flap Endonuclease 1 Mutations A159V and E160D Cause Genomic Instability by Slowing Reaction on Double-Flap Substrates.
- Authors: Algasaier SI, Finger LD, Bennet IA, Grasby JA
- Issue date: 2018 Dec 18
- A conserved loop-wedge motif moderates reaction site search and recognition by FEN1.
- Authors: Thompson MJ, Gotham VJB, Ciani B, Grasby JA
- Issue date: 2018 Sep 6
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