Fig. 1

Comparison of the core domain of Ras superfamily sequences between Rab, Ras and Rho subfamilies. The core domain is aligned showing in uppercase bold, those residues conserved at the 50 % consensus level i.e. at least 50 % sequences show this residue at the position indicated. Bold is also used for positions conserved for positive (+, H, K, R) or negative charge (−, D, E). In lowercase is shown the consensus sequence at non-conserved positions designated according to the amino acid class abbreviation; o (alcohol, S,T), l (aliphatic (I, L,V), a (aromatic, F, H,W,Y), c (charged, D,E,H,K,R), h (hydrophobic, A,C,F,G,H,I,K,L,M,R,T,V,W,Y), p (polar, C,D,E,H,K,N,Q,R,S,T), s (small, A,C,D,G,N,P,S,T,V), u (tiny, A,G,S), t (turn-like, A,C,D,E,G,H,K,N,Q,R,S,T). All residues that are conserved at the 50 % consensus level between the Ras and Rab families are shaded in black. Consensus sequence data were obtained from the SMART database (http://smart.embl-heidelberg.de/) [40] and are derived from 339 Ras domains and 1120 Rab domains. For greater clarification, the G protein conserved sequence elements are shown highlighted in grey. Numbering is arbitrary and intended as a descriptive guide. An asterisk marks the Ras glycine 12 position, this is highly conserved amongst Ras family members and the equivalent residue in at least 50 % of Rab proteins is serine