Plants (Sep 2021)

Identification and Characterization of Rice <i>OsHKT1;3</i> Variants

  • Shahin Imran,
  • Yoshiyuki Tsuchiya,
  • Sen Thi Huong Tran,
  • Maki Katsuhara

DOI
https://doi.org/10.3390/plants10102006
Journal volume & issue
Vol. 10, no. 10
p. 2006

Abstract

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In rice, the high-affinity K+ transporter, OsHKT1;3, functions as a Na+-selective transporter. mRNA variants of OsHKT1;3 have been reported previously, but their functions remain unknown. In this study, five OsHKT1;3 variants (V1-V5) were identified from japonica rice (Nipponbare) in addition to OsHKT1;3_FL. Absolute quantification qPCR analyses revealed that the transcript level of OsHKT1;3_FL was significantly higher than other variants in both the roots and shoots. Expression levels of OsHKT1;3_FL, and some variants, increased after 24 h of salt stress. Two electrode voltage clamp experiments in a heterologous expression system using Xenopus laevis oocytes revealed that oocytes expressing OsHKT1;3_FL and all of its variants exhibited smaller Na+ currents. The presented data, together with previous data, provide insights to understanding how OsHKT family members are involved in the mechanisms of ion homeostasis and salt tolerance in rice.

Keywords