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.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Biosynthesis of the Tonoplast H⁺-ATPase from Oats

Stephen K. Randall and Heven Sze
Plant Physiology
Vol. 89, No. 4 (Apr., 1989), pp. 1292-1298
Stable URL: http://www.jstor.org/stable/4272001
Page Count: 7
  • Read Online (Free)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Biosynthesis of the Tonoplast H⁺-ATPase from Oats
Preview not available

Abstract

To determine whether the tonoplast-type H+-ATPase was differentially synthesized in various parts of the oat seedling, sections of 4-day-old oat (Avena sativa L. var Lang) seedlings were labeled in vivo with [35S]methionine and ATPase subunits were precipitated with polyclonal antisera. ATPase subunits were detected in all portions of the seedling with the exception of the seed. Lesser amounts of the 60 and 72 kilodalton polypeptides of the ATPase were found in apical regions (0-5 millimeter) than in maturing regions (10-15, or 20-25 millimeter from the tip) of the roots or shoots. To initiate a study of the biosynthesis of the ATPase, the intracellular site of synthesis for two peripheral ATPase subunits was investigated. Poly(A) RNA from either free or membrane-bound polysomes was isolated and translated in vitro. Message encoding the 72 kilodalton (catalytic) subunit was found predominantly in mRNA isolated from membrane-bound polysomes. In contrast, the message for the 60 kilodalton (putative regulatory) subunit was found predominantly on free polysomes. Polypeptides synthesized in vivo or obtained from RNA translated in vitro exhibited no apparent size differences (limit of resolution, approximately 1 kilodalton), suggesting the absence of cleaved precursors for the 72 or 60 kilodalton subunits. These data suggest a complex mechanism for the synthesis and assembly of the tonoplast ATPase.

Page Thumbnails

  • Thumbnail: Page 
1292
    1292
  • Thumbnail: Page 
1293
    1293
  • Thumbnail: Page 
1294
    1294
  • Thumbnail: Page 
1295
    1295
  • Thumbnail: Page 
1296
    1296
  • Thumbnail: Page 
1297
    1297
  • Thumbnail: Page 
1298
    1298