Note: In the PDB file this reference is
annotated as "TO BE PUBLISHED". The citation details given above have
been manually determined.
Abstract
DEAD box helicases are involved in nearly all aspects of RNA metabolism. They
share a common helicase core, and may comprise additional domains that
contribute to RNA binding. The Thermus thermophilus helicase Hera is the first
dimeric DEAD box helicase. Crystal structures of Hera fragments reveal a
bipartite C-terminal domain with a novel dimerization motif and an RNA-binding
module. We provide a first glimpse on the additional RNA-binding module outside
the Hera helicase core. The dimerization and RNA-binding domains are connected
to the C-terminal RecA domain by a hinge region that confers exceptional
flexibility onto the helicase, allowing for different juxtapositions of the
RecA-domains in the dimer. Combination of the previously determined N-terminal
Hera structure with the C-terminal Hera structures allows generation of a model
for the entire Hera dimer, where two helicase cores can work in conjunction on
large RNA substrates.
