FIGURE 4.

Structure-based sequence alignment of Rheb from different species, as well as Ras and Rap1A from the rat, and stereoview of the backbone atoms (N, C_α, C′, and O) of the ensemble 〈〈SA〉〉 of 20 rRheb structures. A, invariant residues are highlighted in red-shaded boxes, and open red boxes indicate conserved residues. The secondary structural elements of Rheb are given above the sequence alignment. Residues in blue boxes are discussed in detail throughout the text. B, this superposition shows the lowest root mean square deviation values for the backbone atoms (N, C_α, and C′) of the regions with a regular secondary structure. The unstructured N-terminal residues Ser-1 to Lys-5 and C-terminal residues Ser-175 to Met-184 have been omitted for clarity.