Figure 1.—

Abp1p SH3 domain structure and target peptide sequences. (A) The structure of Abp1p SH3 domain (PDB ID, 1JO8; Fazi et al. 2002). Residues that were mutated in the Abp1p SH3 domain are in red. Other conserved residues that are important for binding are in blue. (B) PxxP-containing target peptides used for in vitro binding assays. The proline residues of the PxxP motif are boxed. The proline residues of a possible alternative PxxP motif in the Scp1p peptide are shaded. The consensus sequence shown here, in which “+” denotes a positively charged residue and “#” denotes a hydrophobic residue, was determined by Fazi et al. (2002).