DNA substrate recognition and processing by the full-length human UPF1 helicase.

ABSTRACT: UPF1 is a conserved helicase required for nonsense-mediated decay (NMD) regulating mRNA stability in the cytoplasm. Human UPF1 (hUPF1) is also needed for nuclear DNA replication. While loss of NMD is tolerated, loss of hUPF1 induces a DNA damage response and cell cycle arrest. We have analysed nucleic acid (NA) binding and processing by full-length hUPF1. hUPF1 unwinds non-B and B-form DNA and RNA substrates in vitro. Unlike many helicases involved in genome stability no hUPF1 binding to DNA structures stabilized by inter-base-pair hydrogen bonding was observed. Alternatively, hUPF1 binds to single-stranded NAs (ssNA) with apparent affinity increasing with substrate length and with no preference for binding RNA or DNA or purine compared to pyrimidine polynucleotides. However, the data show

SUBMITTER: Dehghani-Tafti S 

PROVIDER: S-EPMC5499549 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature