Sequence identity among ZNT1, ZIP4, and
IRT1. The deduced amino acid sequence of
ZNT1 (GenBank accession no. AF133267) is aligned with
the ZIP4 (GenBank accession no. U95973) and
IRT1 (GenBank accession no. U27590) members of the
ZIP gene family, by using the clustal method
in lasergene software (DNAstar, Madison, WI). The predicted
peptide encoded by ZNT1 exhibits 88% sequence identity
to ZIP4 and 34% identity to IRT1; shaded
areas indicate regions of identity to ZNT1. The
asterisks above the sequence alignment identify the histidine-rich
region located in a putative cytoplasmic domain, and the gray bars
indicate the eight potential transmembrane domains predicted by
tmpred (17).