Altered shoot/root Na+ distribution and bifurcating salt sensitivity in Arabidopsis by genetic disruption of the Na+ transporter AtHKT1.
Sodium (Na+) is toxic to most plants, but the molecular mechanisms of plant Na+ uptake and distribution remain largely unknown. Here we analyze Arabidopsis lines disrupted in the Na+ transporter AtHKT1. AtHKT1 is expressed in the root stele and leaf vasculature. athkt1 null plants exhibit lower root Na+ levels and are more salt resistant than wild-type in short-term root growth assays. In shoot tissues, however, athkt1 disruption produces higher Na+ levels, and athkt1 and athkt1/sos3 shoots are Na+-hypersensitive in long-term growth assays. Thus wild-type AtHKT1 controls root/shoot Na+ distribution and counteracts salt stress in leaves by reducing leaf Na+ accumulation.
Mäser
Pascal
P
Division of Biological Sciences, Cell and Developmental Biology Section, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA.
Eckelman
Brendan
B
Vaidyanathan
Rama
R
Horie
Tomoaki
T
Fairbairn
David J
DJ
Kubo
Masahiro
M
Yamagami
Mutsumi
M
Yamaguchi
Katsushi
K
Nishimura
Mikio
M
Uozumi
Nobuyuki
N
Robertson
Whitney
W
Sussman
Michael R
MR
Schroeder
Julian I
JI
D000483:Alleles; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000502:physiology*; D027682:Cation Transport Proteins / Q000235:genetics* / Q000502:physiology*; D046508:Culture Techniques; D009154:Mutation; D018515:Plant Leaves / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism; D010940:Plant Proteins; D018517:Plant Roots / Q000033:anatomy & histology / Q000737:chemistry / Q000254:growth & development; D018520:Plant Shoots / Q000033:anatomy & histology / Q000737:chemistry / Q000254:growth & development; D030821:Plants, Genetically Modified; D018749:RNA, Plant / Q000096:biosynthesis; D036226:Seedlings / Q000033:anatomy & histology / Q000187:drug effects / Q000254:growth & development; D012964:Sodium / Q000032:analysis*; D012965:Sodium Chloride / Q000494:pharmacology*; D027981:Symporters
D029681:Arabidopsis Proteins; D027682:Cation Transport Proteins; C490286:HKT1 protein, Arabidopsis; C088864:HKT1 protein, plant; D010940:Plant Proteins; D018749:RNA, Plant; D027981:Symporters; D012965:Sodium Chloride; D012964:Sodium