Figure 1.

Summary of structures and properties of the five DEAD-box proteins from E.coli. Regions encompassing conserved residues (i.e. helicase core) are shown as open rectangles; stripes denote the positions of the conserved motifs (Q to VI), whereas the N- and C-terminal extensions (drawn to scale) are shown as thin lines. Also indicated are the proposed functions of the proteins, their in vitro activity (+ means that the protein is able to dissociate an RNA duplex in an ATP-dependent manner), and the phenotype associated with the deletion of the gene (no, no visible growth defect; cs, cold-sensitive growth).