Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

Vacuolar citrate/H + symporter of citrus juice cells

Takehiko Shimada, Ryohei Nakano, Vladimir Shulaev, Avi Sadka and Eduardo Blumwald
Planta
Vol. 224, No. 2 (July 2006), pp. 472-480
Published by: Springer
Stable URL: http://www.jstor.org/stable/23389472
Page Count: 9
  • More info
  • Cite this Item
Vacuolar citrate/H
          +
          symporter of citrus juice cells
Preview not available

Abstract

We have isolated a cDNA, designated Citrus sinensis citrate transporter 1 CsCit1 encoding a novel vacuolar citrate/symporter. Immunoblots using antibodies raised against CsCit1 showed that the protein is localized to the juice sac cell vacuoles. The highest expression of CsCit1 and the amount of protein in the juice sac cell vacuoles coincided with the developmental stage at which the vacuolar citrate content began declining with the concomitant increase in vacuolar pH. Vacuoles from Sacharomyces cereviseae expressing CsCit1 displayed a citrate-dependent H+ efflux, and our results clearly demonstrate that CsCit1 is able to mediate the electroneutral co-transport of H+ and citrate ions, since the citrate-dependent H+ fluxes are not affected by changing the electrical potential difference across the tonoplast. The roles of CsCit1 in mediating citrate efflux from the vacuole and on citric acid homoestasis in Citrus juice sac cells are discussed.

Page Thumbnails

  • Thumbnail: Page 
[472]
    [472]
  • Thumbnail: Page 
473
    473
  • Thumbnail: Page 
474
    474
  • Thumbnail: Page 
475
    475
  • Thumbnail: Page 
476
    476
  • Thumbnail: Page 
477
    477
  • Thumbnail: Page 
478
    478
  • Thumbnail: Page 
479
    479
  • Thumbnail: Page 
480
    480