Počet záznamů: 1

BLM helicase measures DNA unwound before switching strands and hRPA promotes unwinding reinitiation

  1. 1.
    0333639 - UMG-J 2010 RIV GB eng J - Článek v odborném periodiku
    Yodh, J.G. - Stevens, B.C. - Kanagaraj, R. - Janščák, Pavel - Ha, T.
    BLM helicase measures DNA unwound before switching strands and hRPA promotes unwinding reinitiation.
    EMBO Journal. Roč. 28, č. 4 (2009), s. 405-416 ISSN 0261-4189
    Výzkumný záměr: CEZ:AV0Z50520514
    Klíčová slova: Bloom syndrome * FRET * helicase * hRPA * single molecule
    Kód oboru RIV: EB - Genetika a molekulární biologie
    Impakt faktor: 8.993, rok: 2009

    Bloom syndrome (BS) is characterized by genomic instability and high predisposition to cancer. BLM, gene defective in BS, encodes a member of the RecQ family of 3´-5´ DNA helicases and is proposed to function in recombinational repair at DNA replication. We used single-molecule fluorescence resonance energy transfer microscopy to examine BLM behaviour on forked DNA substrates. BLM unwound individual DNA molecules repetitively, a short length unwound followed by rapid reannealing in successions. We show that monomeric BLM can "measure" how many base pairs it has unwound, and after a critical length it reverses the unwinding through strand switching and translocating on the opposing strand. Repetitive unwinding persisted even in the presence of hRPA, and interaction between wild-type BLM and hRPA was necessary for unwinding reinitiation on hRPA-coated DNA. These activities may facilitate BLM processing of stalled replication forks and illegitimately formed recombination intermediates.
    Trvalý link: http://hdl.handle.net/11104/0178578