Figure 1.

(A) Scale drawing of the genomic region surrounding the A. thaliana Rab2 locus. The open bar indicates the cloned genomic sequence. The exons are indicated by hatched boxes. The arrow indicates the direction of transcription, and its ends mark the ends of the available cDNA sequence. The asterisk indicates the position of the putative TATA box. E, EcoRI; H, HindIII; S, SalI. (B) The sequence of At-Rab2 (At) and Rab2 homologs from humans (Hs) and the gastropod Lymnaea stagnalis (Ls; ref. 19) were aligned and are shown. The conserved sequences involved in nucleotide binding and hydrolysis (GxxGVGKS, WDTAGQE, GNKxD, and ExSA) are marked by brackets, as are the conserved carboxyl-terminal cysteine residues; over-lining indicates the effector region (corresponding to residues 31–41 of Ha-Ras) and α-helix3 (α3) and loop7 (L7), which contain subfamily specific sequences implicated in determining subfamily specificity. Residues that differ from the mammalian Rab2 sequences are boxed.