Stimulation of H+extrusion and plasma membrane H+-ATPase activity of barley roots by ammonium-treatment

Kousei Yamashita, Bunich Ezaki, Mineo Shibasaka, Yoko Yamamoto, Hideo Sasakawa, Minobu Kasai, Hideaki Matsumoto

Research output: Contribution to journalArticlepeer-review

21 Citations (Scopus)


H+extrusion and the plasma membrane H+-ATPase activity were analyzed using barley roots exposed to ammonium. H+extrusion from roots was enhanced 4 h after the addition of 5 mol m-3ammonium to the medium. However, the stimulation of the plasma membrane H+-ATPase activity occurred at least 8 h after the addition of ammonium. Furthermore, this stimulation was found to be caused by the increase in the content of H+-ATPase proteins based on the results of immunoassay. These results indicate that H+was actively extruded to the medium through the increase in the amount of plasma membrane H+-ATPase proteins, when barley roots were exposed to ammonium for more than 8 h. Thus, it is assumed that in the long term exposure to ammonium nitrogen, ammonium-induced stimulation of the H+-ATPase activity may be important to maintain intracellular pH in root cells under the acidic conditions associated with the uptake of ammonium.

Original languageEnglish
Pages (from-to)133-140
Number of pages8
JournalSoil Science and Plant Nutrition
Issue number1
Publication statusPublished - Mar 1995
Externally publishedYes


  • Ammonium
  • Barley roots
  • Hextrusion
  • Plasma membrane
  • Stimulation of H-ATPase

ASJC Scopus subject areas

  • Soil Science
  • Plant Science


Dive into the research topics of 'Stimulation of H<sup>+</sup>extrusion and plasma membrane H<sup>+</sup>-ATPase activity of barley roots by ammonium-treatment'. Together they form a unique fingerprint.

Cite this