Radiocesium accumulated in the soil by nuclear accidents is a major environmental concern.The transport process of cesium (Cs*) is tightly linked to the indispensable plant nutrient potassium (K*) as they both belong to the group Ⅰ alkali metals with similar chemical properties.Most of the transporters that had been characterized to date as Cs+ transporters are directly or indirectly linked to K+.Using a combinatoria approach of physiology,genetics,cell biology,and root uptake assay,here we identified two ATP-binding cassette (ABC) proteins,ABCG37 and ABCG33,as facilitators of Cs+ influx.A gain-of-function mutant of ABCG37 (abcg37-1) showed increased sensitivity toCs+-induced root growth inhibition,while the double knockout mutant of ABCG33 and ABCG37 (abcg33-1abcg37-2) showed resistance,whereas the single loss-of-function mutants of ABCG33 and ABCG37 did not show any alteration in Cs+ response.In planta short-term radioactive Cs*-uptake assay along with growth and uptake assays in a heterologous system confirmed ABCG33 and ABCG37 as Cs+-uptake carriers.Potassium response and content were unaffected in the double-mutant background and yeast cells lacking potassium-uptake carriers transformed with ABCG33 and ABCG37 failed to grow in the absence of K*,confirming that Cs* uptake by ABCG33 and ABCG37 is independent of K+.Collectively,this work identified two ABC proteins as new Cs+-influx carriers that act redundantly and independent of the K+-uptake pathway.