Model of Cation Transportation Mediated by High-Affinity Potassium Transporters (HKTs) in Higher Plants.

Yi Su,Mohammed Hunayun Kabir,Liying Ma,Wanhuang Lin,Weigui Luo

doi:10.1186/s12575-014-0013-3

Yi Su, Mohammed Hunayun Kabir + Show 3 more

Open Access

https://doi.org/10.1186/s12575-014-0013-3

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Abstract

Trk/Ktr/HKT transporters probably were evolved from simple K+ channels KcsA. HKT transporters, which mediate Na+-uniport or Na+/K+-symport, maintain K+/Na+ homeostasis and increase salinity tolerance, can be classified into three subfamilies in higher plants. In this review, we systematically analyzed the characteristics of amino acids sequences and physiological functions of HKT transporters in higher plant. Furthermore, we depicted the hypothetical models of cations selection and transportation mediated by HKT transporters according to the highly conserved structure for the goal of better understanding the cations transportation processes.

Highlights

Sodium (Na), unlike potassium (K), is not an essential nutrient element for the most of higher plants but may be a beneficial element for some species [1,2,3]
Conclusions and future directions Trk/Ktr/HKT were generally thought to be evolved from the bacterial KcsA K+ channel [109] and contain four conserved MPM motifs [55,58,65,110]
I was characterized by SerGlyGlyGly but subfamily II and III were GlyGlyGlyGlytype HKTs exception of OsHKT2;1

Summary

Introduction

Sodium (Na), unlike potassium (K), is not an essential nutrient element for the most of higher plants but may be a beneficial element for some species [1,2,3]. Plant HKT transporter is a multiple cation uptake system, which can mediate Na+ uniport, Na+/K+-symport and even Mg2+/Ca2+ permeation. I members of HKT transporters contain a highly conserved serine (Ser) residue in the first motif MPAM, whereas subfamily II members primarily have glycine (Gly) residue with the exception of OsHKT2;1.

Results

Conclusion