(a) Results of amino acid database searches for exon 2 identifying a number of sequence matches with the Pro/Ser-rich putative SH3 binding domain of NRAMP; (+) a conserved amino acid. Residues showing four or more identities are in bold. Multiple sequence alignments allowed for the generation of a consensus motif over this region (double underlining). Also shown is the PKC site on S40, and tyrosine residues (*) on either side of the consensus motif. (b) Clustal V multiple sequence alignment for human NRAMP, mouse Nramp, SMF1 and SMF2, and the expressed sequence tags (40) of Oryza sativa (rice; accession number d15268) and Arabidopsis thaliana (accession number z30530) genes, reading Frames 1 and 2 respectively. Residues showing ≥4/6 identities across the six proteins are in bold. Membrane spanning domains 6 and 7 for NRAMP are overlined and numbered on the sequence. The 20 amino acid conserved transport motif (1) is indicated by double overlining. All six proteins show identities (similarities) of 7/20 (11/20) across the transport motif. *Cysteine residues conserved across all 6 proteins; (·) conserved substitutions.