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.

Subcellular Visualization of Gene Transcripts Encoding Key Proteins of the Chlorophyll Accumulation Process in Developing Chloroplasts

Joanne L. Marrison, Petra H. D. Schünmann, Helen J. Ougham and Rachel M. Leech
Plant Physiology
Vol. 110, No. 4 (Apr., 1996), pp. 1089-1096
Stable URL: http://www.jstor.org/stable/4277091
Page Count: 8
  • 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.
Subcellular Visualization of Gene Transcripts Encoding Key Proteins of the Chlorophyll Accumulation Process in Developing Chloroplasts
Preview not available

Abstract

The coordination of the synthesis of chlorophyll (Chl) and light-harvesting Chl proteins was determined by observing the sequence of appearance of the specific mRNAs for the nuclear genes CHLH, Por, and $Lhcb1^{\ast }2$ (AB180). CHLH encodes a magnesium protoporphyrin chelatase subunit that is involved in the first committed step in Chl biosynthesis; Por encodes protochlorophyllide oxidoreductase, which catalyzes the penultimate and only light-dependent step in Chl biosynthesis; and $Lhcb1^{\ast }2$ encodes light-harvesting Chl a/b binding protein of the type-1 light-harvesting complex of photosystem II. Using digoxigenin-labeled antisense and sense RNA probes and a highly sensitive in situ hybridization technique, we have visualized the first appearance of the specific mRNAs in postmitotic mesophyll cells of developing 7-d-old wheat leaves (Triticum aestivum cv Maris dove). The transcripts for CHLH and POR are detectable in the youngest (18 h postmitotic) leaf tissue containing dividing cells; light-harvesting complex of photosystem II transcripts appear 12 h later. This is consistent with a requirement for accumulation of Chl before synthesis of Chl a/b binding protein can proceed at a high rate. All of the transcripts are most abundant in mesophyll cells. In the first leaf the POR message is initially restricted to the palisade, but 12 h later it is also present in the spongy mesophyll cells. All three transcripts aggregated around the surface of the chloroplasts, suggesting that translation may occur preferentially in the vicinity of the target organelle for the primary translation products.

Page Thumbnails

  • Thumbnail: Page 
1089
    1089
  • Thumbnail: Page 
1090
    1090
  • Thumbnail: Page 
1091
    1091
  • Thumbnail: Page 
1092
    1092
  • Thumbnail: Page 
1093
    1093
  • Thumbnail: Page 
1094
    1094
  • Thumbnail: Page 
1095
    1095
  • Thumbnail: Page 
1096
    1096