5y7q
From Proteopedia
(Difference between revisions)
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| - | ==Crystal structure of | + | ==Crystal structure of paFAN1 bound to 2nt 5'flap DNA with gap== |
<StructureSection load='5y7q' size='340' side='right' caption='[[5y7q]], [[Resolution|resolution]] 2.70Å' scene=''> | <StructureSection load='5y7q' size='340' side='right' caption='[[5y7q]], [[Resolution|resolution]] 2.70Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
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== Function == | == Function == | ||
[[http://www.uniprot.org/uniprot/FAN1_PSEAE FAN1_PSEAE]] Nuclease required for the repair of DNA interstrand cross-links (ICL). Acts as a 5'-3' exonuclease that anchors at a cut end of DNA and cleaves DNA successively at every third nucleotide, allowing to excise an ICL from one strand through flanking incisions. Also has endonuclease activity toward 5'-flaps (PubMed:25319828).[UniProtKB:Q9Y2M0]<ref>PMID:24981866</ref> <ref>PMID:25319828</ref> | [[http://www.uniprot.org/uniprot/FAN1_PSEAE FAN1_PSEAE]] Nuclease required for the repair of DNA interstrand cross-links (ICL). Acts as a 5'-3' exonuclease that anchors at a cut end of DNA and cleaves DNA successively at every third nucleotide, allowing to excise an ICL from one strand through flanking incisions. Also has endonuclease activity toward 5'-flaps (PubMed:25319828).[UniProtKB:Q9Y2M0]<ref>PMID:24981866</ref> <ref>PMID:25319828</ref> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | DNA interstrand cross-links (ICLs) block the progress of the replication and transcription machineries and can weaken chromosomal stability, resulting in various diseases. FANCD2-FANCI-associated nuclease (FAN1) is a conserved structure-specific nuclease that unhooks DNA ICLs independently of the Fanconi anemia pathway. Recent structural studies have proposed two different mechanistic features for ICL unhooking by human FAN1: a specific basic pocket that recognizes the terminal phosphate of a 1-nucleotide (nt) 5' flap or FAN1 dimerization. Herein, we show that despite lacking these features, Pseudomonas aeruginosa FAN1 (PaFAN1) cleaves substrates at approximately 3-nt intervals and resolves ICLs. Crystal structures of PaFAN1 bound to various DNA substrates revealed that its conserved basic Arg/Lys patch comprising Arg-228 and Lys-260 recognizes phosphate groups near the 5' terminus of a DNA substrate with a 1-nt flap or a nick. Substitution of Lys-260 did not affect PaFAN1's initial endonuclease activity but significantly decreased its subsequent exonuclease activity and ICL unhooking. The Arg/Lys patch also interacted with phosphates at a 3-nt gap, and this interaction could drive movement of the scissile phosphates into the PaFAN1-active site. In human FAN1, the ICL-resolving activity was not affected by individual disruption of the Arg/Lys patch or basic pocket. However, simultaneous substitution of both FAN1 regions significantly reduced its ICL-resolving activity, suggesting that these two basic regions play a complementary role in ICL repair. On the basis of these findings, we propose a conserved role for two basic regions in FAN1 to guide ICL unhooking and to maintain genomic stability. | ||
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| + | Structural mechanism of DNA interstrand cross-link unhooking by the bacterial FAN1 nuclease.,Jin H, Roy U, Lee G, Scharer OD, Cho Y J Biol Chem. 2018 Apr 27;293(17):6482-6496. doi: 10.1074/jbc.RA118.002171. Epub, 2018 Mar 7. PMID:29514982<ref>PMID:29514982</ref> | ||
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| + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| + | </div> | ||
| + | <div class="pdbe-citations 5y7q" style="background-color:#fffaf0;"></div> | ||
== References == | == References == | ||
<references/> | <references/> | ||
Revision as of 06:29, 9 May 2018
Crystal structure of paFAN1 bound to 2nt 5'flap DNA with gap
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