Polyclonal Antibody Preparation and Expression Analysis of High-affinity K⁺ Transporter SsHKT1

We isolated a cDNA homologous to HKT1 from Suaeda salsa L.(SsHKT1) roots using RT-PCR and RACE methods.The hydrophilic fragment(403-612 bp) was amplified by PCR from SsHKT1 cDNA of halophyte S.salsa L.PCR product was inserted into prokaryotic expression vector pGEX-6P-3.The recombinant vector was transformed into Escherichia coli BL21(DE3) and the GST-SsHKT1 fusion protein expression was induced by IPTG.The fusion protein was mainly in inclusion bodies.The purified protein was injected into a New Zealand rabbit and the rabbit’s anti-serum against SsHKT1 with higher specificity was prepared.Western-blot analysis using this polyclonal antibody demonstrated that SsHKT1 may be localized to the plasma membrane.Further study shows that level of SsHKT1 proteins increase under conditions of K⁺ starvation or salt stress.These datas suggest that SsHKT1 is important for K⁺ uptake of S.salsa L.and particularly for K⁺ nutrition under high salt conditions in this plant.