4REB image
Entry Detail
PDB ID:
4REB
Keywords:
Title:
Structural Insights into 5' Flap DNA Unwinding and Incision by the Human FAN1 Dimer
Biological Source:
Host Organism:
PDB Version:
Deposition Date:
2014-09-22
Release Date:
2014-12-24
Method Details:
Experimental Method:
Resolution:
4.20 Å
R-Value Free:
0.26
R-Value Work:
0.23
R-Value Observed:
0.23
Space Group:
P 31
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:Fanconi-associated nuclease 1
Mutations:D960A
Chain IDs:D (auth: A), E (auth: H)
Chain Length:647
Number of Molecules:2
Biological Source:Homo sapiens
Polymer Type:polydeoxyribonucleotide
Description:DNA (5'-D(P*GP*TP*GP*GP*CP*GP*AP*GP*C)-3')
Chain IDs:A (auth: D)
Chain Length:9
Number of Molecules:1
Biological Source:synthetic construct
Polymer Type:polydeoxyribonucleotide
Description:DNA (5'-D(P*CP*GP*TP*GP*GP*CP*GP*AP*GP*CP*GP*CP*TP*CP*GP*CP*CP*AP*CP*G)-3')
Chain IDs:B (auth: E)
Chain Length:20
Number of Molecules:1
Biological Source:synthetic construct
Polymer Type:polydeoxyribonucleotide
Description:DNA (5'-D(P*GP*CP*TP*CP*GP*CP*CP*AP*CP*G)-3')
Chain IDs:C (auth: F)
Chain Length:10
Number of Molecules:1
Biological Source:synthetic construct
Ligand Molecules
Primary Citation
Structural insights into 5' flap DNA unwinding and incision by the human FAN1 dimer.
Nat Commun 5 5726 5726 (2014)
PMID: 25500724 DOI: 10.1038/ncomms6726

Abstact

Human FANCD2-associated nuclease 1 (FAN1) is a DNA structure-specific nuclease involved in the processing of DNA interstrand crosslinks (ICLs). FAN1 maintains genomic stability and prevents tissue decline in multiple organs, yet it confers ICL-induced anti-cancer drug resistance in several cancer subtypes. Here we report three crystal structures of human FAN1 in complex with a 5' flap DNA substrate, showing that two FAN1 molecules form a head-to-tail dimer to locate the lesion, orient the DNA and unwind a 5' flap for subsequent incision. Biochemical experiments further validate our model for FAN1 action, as structure-informed mutations that disrupt protein dimerization, substrate orientation or flap unwinding impair the structure-specific nuclease activity. Our work elucidates essential aspects of FAN1-DNA lesion recognition and a unique mechanism of incision. These structural insights shed light on the cellular mechanisms underlying organ degeneration protection and cancer drug resistance mediated by FAN1.

Legend

Protein

Chemical

Disease

Primary Citation of related structures