Isolation and characterization of a cDNA encoding a sulfate transporter fromArabidopsis thaliana

Abstract
A cDNA encoding a sulfate transporter was isolated from Arabidopsis thaliana. The isolated clone contained an open reading frame encoding a polypeptide of 658 amino acids, exhibiting the highest similarity (62%) with the sequence of the low-affinity sulfate transporter of a tropical legume Stylosanthes hamata. Northern blot analysis indicated the constitutive accumulation of a 2.6 kb length transcript in leaves and roots of seedlings. We also propose that A. thaliana contains three sulfate transporter genes which are expressed as 3.0, 2.7 and 2.6 kb length transcripts, respectively, in an organ-specific manner.