WRN Protein, Human (His)

WRN Protein, Human (His) is the recombinant human-derived WRN protein, expressed by E. coli, with N-His tag.

WRN is a multifunctional enzyme with magnesium and ATP-dependent 3'-5' DNA helicase activity on partially duplex substrates. It also exhibits 3'->5' exonuclease activity towards double-stranded (ds)DNA with a 5'-overhang but has no nuclease activity towards single-stranded (ss)DNA or blunt-ended dsDNA. Helicase activity is most efficient with (d)ATP, while (d)CTP can substitute with reduced efficiency; strand displacement is enhanced by single-strand binding-protein (heterotrimeric replication protein A complex, RPA1, RPA2, RPA3). WRN preferentially binds DNA substrates containing alternate secondary structures, such as replication forks and Holliday junctions, and may play a crucial role in dissociating joint DNA molecules arising from homologous recombination, stalled replication forks, or DNA repair. It alleviates stalling of DNA polymerases at DNA lesion sites and contributes to the formation of DNA replication focal centers by stably associating with foci elements to generate binding sites for RP-A (by similar). WRN is involved in double-strand break repair after gamma-irradiation and unwinds certain G-quadruplex DNA (d(CGG)n tracts), with unwinding occurring bidirectionally (5'-3' and 3'-5') and requiring a short single-stranded tail. d(CGG)n tracts tend to form tetraplex structures, while other G-rich substrates from telomeric or IgG switch sequences are not unwound. Depletion of WRN leads to chromosomal breaks and genome instability.

Human

E. coli

N-His

Q14191 (S2-I333)

7486

Partial

SEKKLETTAQQRKCPEWMNVQNKRCAVEERKACVRKSVFEDDLPFLEFTGSIVYSYDASDCSFLSEDISMSLSDGDVVGFDMEWPPLYNRGKLGKVALIQLCVSESKCYLFHVSSMSVFPQGLKMLLENKAVKKAGVGIEGDQWKLLRDFDIKLKNFVELTDVANKKLKCTETWSLNSLVKHLLGKQLLKDKSIRCSNWSKFPLTEDQKLYAATDAYAGFIIYRNLEILDDTVQRFAINKEEEILLSDMNKQLTSISEEVMDLAKHLPHAFSKLENPRRVSILLKDISENLYSLRRMIIGSTNIETELRPSNNLNLLSFEDSTTGGVQQKQI

Approximately 40-43 kDa, based on SDS-PAGE under reducing conditions.

Greater than 90% as determined by reducing SDS-PAGE.

<1 EU/μg, determined by LAL method.