The trimeric Hef-associated nuclease HAN is a 3'â5' exonuclease and is probably involved in DNA repair.
Nucleic Acids Res
; 46(17): 9027-9043, 2018 09 28.
Article
en En
| MEDLINE
| ID: mdl-30102394
ABSTRACT
Nucleases play important roles in nucleic acid metabolism. Some archaea encode a conserved protein known as Hef-associated nuclease (HAN). In addition to its C-terminal DHH nuclease domain, HAN also has three N-terminal domains, including a DnaJ-Zinc-finger, ribosomal protein S1-like, and oligonucleotide/oligosaccharide-binding fold. To further understand HAN's function, we biochemically characterized the enzymatic properties of HAN from Pyrococcus furiosus (PfuHAN), solved the crystal structure of its DHH nuclease domain, and examined its role in DNA repair. Our results show that PfuHAN is a Mn2+-dependent 3'-exonuclease specific to ssDNA and ssRNA with no activity on blunt and 3'-recessive double-stranded DNA. Domain truncation confirmed that the intrinsic nuclease activity is dependent on the C-terminal DHH nuclease domain. The crystal structure of the DHH nuclease domain adopts a trimeric topology, with each subunit adopting a classical DHH phosphoesterase fold. Yeast two hybrid assay confirmed that the DHH domain interacts with the IDR peptide of Hef nuclease. Knockout of the han gene or its C-terminal DHH nuclease domain in Haloferax volcanii resulted in increased sensitivity to the DNA damage reagent MMS. Our results imply that HAN nuclease might be involved in repairing stalled replication forks in archaea.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
ADN de Cadena Simple
/
Proteínas Arqueales
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ARN de Archaea
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Pyrococcus furiosus
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Reparación del ADN
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Exonucleasas
Tipo de estudio:
Risk_factors_studies
Idioma:
En
Revista:
Nucleic Acids Res
Año:
2018
Tipo del documento:
Article
País de afiliación:
China