TsHKT1;2, a HKT1 Homolog from the Extremophile Arabidopsis Relative Thellungiella salsuginea, Shows K+ Specificity in the Presence of NaCl

被引：129

作者：

Ali, Zahir ^{[1
,2
,3
]}

Park, Hyeong Cheol ^{[1
,2
]}

Ali, Akhtar ^{[1
,2
]}

Oh, Dong-Ha ^{[4
]}

Aman, Rashid ^{[1
,2
]}

Kropornicka, Anna ^{[4
]}

Hong, Hyewon ^{[1
,2
]}

Choi, Wonkyun ^{[1
,2
]}

Chung, Woo Sik ^{[1
,2
]}

Kim, Woe-Yeon ^{[1
,2
]}

Bressan, Ray A. ^{[1
,2
,3
,6
]}

Bohnert, Hans J. ^{[1
,2
,3
,4
,5
]}

Lee, Sang Yeol ^{[1
,2
]}

Yun, Dae-Jin ^{[1
,2
]}

机构：

[1] Gyeongsang Natl Univ, Div Appl Life Sci, Brain Korea Program 21, Jinju 660701, South Korea

[2] Gyeongsang Natl Univ, Plant Mol Biol & Biotechnol Res Ctr, Jinju 660701, South Korea

[3] King Abdulaziz Univ, Genom & Biotechnol Sect, Dept Biol Sci, Fac Sci, Jeddah 21589, Saudi Arabia

[4] Univ Illinois, Dept Plant Biol, Urbana, IL 61801 USA

[5] Univ Illinois, Dept Crop Sci, Urbana, IL 61801 USA

[6] Purdue Univ, Dept Hort & Landscape Architecture, W Lafayette, IN 47907 USA

来源：

PLANT PHYSIOLOGY | 2012年 / 158卷 / 03期

关键词：

HIGH-AFFINITY POTASSIUM; SALT TOLERANCE; NA+ TRANSPORT; ABIOTIC STRESS; SALINITY TOLERANCE; GENE; HALOPHILA; SOS1; HOMEOSTASIS; EVOLUTION;

D O I：

10.1104/pp.111.193110

中图分类号：

Q94 [植物学];

学科分类号：

071001 ;

摘要：

Cellular Na+/K+ ratio is a crucial parameter determining plant salinity stress resistance. We tested the function of plasma membrane Na+/K+ cotransporters in the High-affinity K+ Transporter (HKT) family from the halophytic Arabidopsis (Arabidopsis thaliana) relative Thellungiella salsuginea. T. salsuginea contains at least two HKT genes. TsHKT1;1 is expressed at very low levels, while the abundant TsHKT1;2 is transcriptionally strongly up-regulated by salt stress. TsHKT-based RNA interference in T. salsuginea resulted in Na+ sensitivity and K+ deficiency. The athkt1 mutant lines overexpressing TsHKT1;2 proved less sensitive to Na+ and showed less K+ deficiency than lines overexpressing AtHKT1. TsHKT1;2 ectopically expressed in yeast mutants lacking Na+ or K+ transporters revealed strong K+ transporter activity and selectivity for K+ over Na+. Altering two amino acid residues in TsHKT1;2 to mimic the AtHKT1 sequence resulted in enhanced sodium uptake and loss of the TsHKT1;2 intrinsic K+ transporter activity. We consider the maintenance of K+ uptake through TsHKT1; 2 under salt stress an important component supporting the halophytic lifestyle of T. salsuginea.

引用

页码：1463 / 1474

页数：12