exonuclease 5; exo V; hexo5; defects in morphology protein 1 homolog (EXO5, C1orf176, DEM1)

Function

• single-stranded DNA (ssDNA) bidirectional exonuclease involved in DNA repair
• probably involved in DNA repair following ultraviolet (UV) irradiation & interstrand cross-links
• has both 5'-3' & 3'-5' exonuclease activities with a strong preference for 5'-ends
• acts as a sliding exonuclease that loads at ssDNA ends & then slides along the ssDNA prior to cutting
  • sliding & 3'-5' exonuclease activities are abolished upon binding to the replication protein A complex that enforces 5'-directionality activity
• monomer;
  • monomeric form has weak exonuclease activity
• homodimer;
  • homodimeric has much higher exonuclease activity,
  • could homodimerize upon DNA-binding
• interacts with the replication protein A complex

Cofactor:

• binds 1 4Fe-4S cluster
• Mg+2 (putative)

Structure

belongs to the EXO5 family

Compartment

• nucleus. cytoplasm
• localizes to repair foci in response to DNA damage

More general terms

• exonuclease
• nuclear protein

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=64789
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:64789
• UniProt: http://www.uniprot.org/uniprot/Q9H790.html