RT-PCR analyses of the three BjSultr1;2 forms in the roots of Brassica juncea grown under Cd exposure or sulfate limitation. Plants were exposed to 25 μM Cd2+ for 48 h (A, B) or grown under 10 μM SO4 2- for 10 days (C, D). (A, C) The entire ORFs of the three BjSultr1;2 forms were amplified and PCR products, digested (d) or not digested (u) with ClaI endonuclease, were electrophoresed on agarose gel and stained with SYBR Green I. cDNA loading was normalized using BjTub as an internal control. Signals were detected using a laser scanner with 532 nm laser and 526 nm filter. (B, D) Densitometric analysis. Arrows indicate the relative position of each electrophoretic band obtained after digestion of PCR products with ClaI. A representative set of data from three independent experiments is given. For statistical analysis, see Additional file 9.