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.

Structure and Function of a Mitochondrial Late Embryogenesis Abundant Protein Are Revealed by Desiccation

Dimitri Tolleter, Michel Jaquinod, Cécile Mangavel, Catherine Passirani, Patrick Saulnier, Stephen Manon, Emeline Teyssier, Nicole Payet, Marie-Hélène Avelange-Macherel and David Macherel
The Plant Cell
Vol. 19, No. 5 (May, 2007), pp. 1580-1589
Stable URL: http://www.jstor.org/stable/20077041
Page Count: 10
  • 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.
Structure and Function of a Mitochondrial Late Embryogenesis Abundant Protein Are Revealed by Desiccation
Preview not available

Abstract

Few organisms are able to withstand desiccation stress; however, desiccation tolerance is widespread among plant seeds. Survival without water relies on an array of mechanisms, including the accumulation of stress proteins such as the late embryogenesis abundant (LEA) proteins. These hydrophilic proteins are prominent in plant seeds but also found in desiccation-tolerant organisms. In spite of many theories and observations, LEA protein function remains unclear. Here, we show that LEAM, a mitochondrial LEA protein expressed in seeds, is a natively unfolded protein, which reversibly folds into α-helices upon desiccation. Structural modeling revealed an analogy with class A amphipathic helices of apolipoproteins that coat low-density lipoprotein particles in mammals. LEAM appears spontaneously modified by deamidation and oxidation of several residues that contribute to its structural features. LEAM interacts with membranes in the dry state and protects liposomes subjected to drying. The overall results provide strong evidence that LEAM protects the inner mitochondrial membrane during desiccation. According to sequence analyses of several homologous proteins from various desiccation-tolerant organisms, a similar protection mechanism likely acts with other types of cellular membranes.

Page Thumbnails

  • Thumbnail: Page 
[1580]
    [1580]
  • Thumbnail: Page 
1581
    1581
  • Thumbnail: Page 
1582
    1582
  • Thumbnail: Page 
1583
    1583
  • Thumbnail: Page 
1584
    1584
  • Thumbnail: Page 
1585
    1585
  • Thumbnail: Page 
1586
    1586
  • Thumbnail: Page 
1587
    1587
  • Thumbnail: Page 
1588
    1588
  • Thumbnail: Page 
1589
    1589