<p>The domain, which defines this group of proteins is found in a wide variety of helicases and helicase related proteins. It may be that this is not an autonomously folding unit, but an integral part of the helicase.</p><p>The eukaryotic translation initiation factor 4A (eIF4A) is a member of the DEA(D/H)-box RNA helicase family This is a diverse group of proteins that couples an ATPase activity to RNA binding and unwinding. The structure of the carboxyl-terminal domain of eIF4A has been determined to 1.75 A resolution; it has a parallel alpha-beta topology that superimposes, with minor variations, on the structures and conserved motifs of the equivalent domain in other, distantly related helicases [<cite idref="PUB00025034"/>].</p>