None of the predicted amino acid sequences for the Arabidopsis APTs appear to contain transit signaling peptides although APTs have been localized to plastids and mitochondria in other plants
To investigate the subcellular localization of APT1, 2 and 3, peptide antibodies specific for
each isoform were prepared and used to probe immunoblots of subcellular fractions of Arabidopsis
leaves. Based on these analyses, APT1 and 3 are cytosolic while the data for APT2 were nconclusive