Limited proteoloysis experiments show there is a large N-terminal domain with ATPase/helicase functions and a non-essential C-terminal domain (HRDC) (PubMed:12771204). The N-terminal 21 residues are required for helicase and ATPase activity, the C-terminal HRDC domain is required for stable DNA-binding but not ATPase or helicase activity (PubMed:12771204). Has 5 structural subdomains; the first 2 (residues 1-208 and 209-340) are the conserved helicase domains which abut and form a deep cleft that probably binds ATP and ssDNA (PubMed:14517231). The third (residues 341-406) forms a platform of helices sandwiched between the helicase and next domain and binds a Zn(2+) ion (PubMed:14517231). The fourth domain (residues 407-516) forms a helix-turn-helix WH-type subdomain (PubMed:14517231). A large cleft forms between the Zn-binding and WH subdomains which might bind dsDNA (PubMed:14517231). The fifth HRDC domain (residues 524-609) forms a globular bundles of helices, and as a single domain binds preferentially to ssDNA via an elongated binding site that wraps along its surface; in the whole protein alters the type of DNA substrate bound (PubMed:16084389).
An ATP-dependent DNA helicase which unwinds DNA in a 3'-5' direction (PubMed:12771204, PubMed:16084389, PubMed:2164680, PubMed:9553043). ATPase activity is stimulated by ssDNA but only very poorly by dsDNA (PubMed:2164680). Binds to and unwinds a wide variety of substrates including 3- and 4-way junctions (including Holliday junctions), flayed duplexes, 5'- and 3'-overhangs and blunt end duplexes (PubMed:19151156, PubMed:9553043). Unwinds G-quadruplex DNA (PubMed:11292849). Unlike yeast SGS1 or human BLM, is equally active on dsDNA versus G-quadruplex substrates (PubMed:11292849). Can act as an initiator during homologous recombination; unwinds a linear dsDNA substrate which can be used by RecA to initiate homologous DNA pairing as well as dissociation (PubMed:9553043). The identity of a few residues in the C-terminal HRDC domain influences the type of DNA substrate bound (PubMed:16084389). Involved in the RecF recombination pathway (PubMed:2993821).
Belongs to the helicase family. RecQ subfamily.
b3822, JW5855, recQ, ATP-dependent DNA helicase RecQ, DNA 3'-5' helicase RecQ
Proteins
68364Da
We found 1 product in 1 category