Structures and ion transport mechanisms of plant high-affinity potassium transporters
作者机构:international Institutes of Medicinethe Fourth Affiliated HospitalZhejang University School of MedicineYiwuZhejiang 322000China Department of Biophysics and Department of Neurology of the Fourth Affiliated HospitalZhejiang University School of MedicineHangzhouZhejang 310058China State Key Laboratory of Plant Environmental ResilienceCollege of Life SciencesZhejang UniversityHangzhouZhejang 310058China College of Life SciencesZhejiang UniversityHangzhouZhejiang 310058China NHC and CAMS Key Laboratory of Medical NeurobiologyMOE Frontier Science Center for Brain Science and Brain-machine IntegrationSchool of Brain Science and Brain MedicineZhejiang UniversityHangzhouZhejiang 310058China Nanhu Brain-computer Interface InstituteHangzhou.Zheiang 311100.China
出 版 物:《Molecular Plant》 (分子植物(英文版))
年 卷 期:2024年第17卷第3期
页 面:409-422页
核心收录:
学科分类:0710[理学-生物学] 071001[理学-植物学] 07[理学]
基 金:supported in part by the National Key Research and Development Program of China(2022YFA1303400 to S.J.Z.and S.Q.,2020YFA0908501 to J.G.,and 2021YFF1200404 to Y.W.) the National Natural Science Foundation of China(32371204 to J.G.,82030108 and 31872796 to W.Y.,and 32371300 to Y.W.) Zhejiang Provincial Natural Science Foundation(LR19C050002 to J.G.) the China Postdoctoral Science Foundation(no.74,2023M743044 to J.W.) the National Postdoctoral Researcher Program of China(GZB20230634 to J.W.)
主 题:HKTs structure ion selectivity mechanism salt tolerance
摘 要:Plant high-affinity K^(+) transporters(HKTs)mediate Na^(+) and K^(+) uptake,maintain Na^(+)/K^(+) homeostasis,and therefore play crucial roles in plant salt *** this study,we present cryoelectron microscopy structures of HKTs from two classes,classI HKT1;1 from Arabidopsis thaliana(AtHKT1;1)and class II HKT2;1 from Triticum aestivum(TaHKT2;1),in both Na^(+) -and K^(+) -bound states at 2.6-to 3.0-A ***1;1and TaHKT2;1function *** HKT subunit consists of four tan-dem domain units(D1-D4)with a repeated K^(+) -channel-like M-P-M *** each subunit,D1-D4 assemble into an ion conduction pore with a pseudo-four-fold *** both TaHKT2;1and AtHKT1;1 have only one putative Na^(+) ion bound in the selectivity filter with a similar coordination pattern,the two HKTs display different K^(+) binding modes in the ***2;1 has three K^(+) ions bound in the selec-tivity filter,but AtHKT1;1 has only two K^(+) ions bound in the filter,which has a narrowed external entrance due to the presence of a Ser residue in the first filter *** structures,along with compu-tational,mutational,and electrophysiological analyses,enable us to pinpoint key residues that are critical for the ion selectivity of *** findings provide new insights into the ion selectivity and ion transport mechanisms of plant HKTs and improve our understanding about how HKTs mediate plant salt tolerance and enhance crop growth.