MCB
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Rott, R.
Right arrow Articles by Schuster, G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Rott, R.
Right arrow Articles by Schuster, G.

 Previous Article  |  Next Article 

Mol Cell Biol, August 1998, p. 4605-4611, Vol. 18, No. 8
0270-7306/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.

3'-Processed mRNA Is Preferentially Translated in Chlamydomonas reinhardtii Chloroplastsdagger

Ruth Rott,1 Haim Levy,2 Dagger Robert G. Drager,2 David B. Stern,2 and Gadi Schuster1 *

Department of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel,1 and Boyce Thompson Institute for Plant Research, Cornell University, Ithaca, New York 148532

Received 27 January 1998/Returned for modification 12 March 1998/Accepted 7 May 1998

3'-end processing of nucleus-encoded mRNAs includes the addition of a poly(A) tail that is important for translation initiation. Since the vast majority of chloroplast mRNAs acquire their 3' termini by processing yet are not polyadenylated, we asked whether 3' end maturation plays a role in chloroplast translation. A general characteristic of the 3' untranslated regions of chloroplast mRNAs is an inverted repeat (IR) sequence that can fold into a stem-loop structure. These stem-loops and their flanking sequences serve as RNA 3'-end formation signals. Deletion of the Chlamydomonas chloroplast atpB 3' IR in strain Delta 26 results in reduced accumulation of atpB transcripts and the chloroplast ATPase beta -subunit, leading to weakly photosynthetic growth. Of the residual atpB mRNA in Delta 26, approximately 1% accumulates as a discrete RNA of wild-type size, while the remainder is heterogeneous in length due to the lack of normal 3' end maturation. In this work, we have analyzed whether these unprocessed atpB transcripts are actively translated in vivo. We found that only the minority population of discrete transcripts of wild-type size is associated with polysomes and thus accounts for the ATPase beta -subunit which accumulates in Delta 26. Analysis of chloroplast rbcL mRNA revealed that transcripts extending beyond the mature 3' end were not polysome associated. These results suggest that 3'-end processing of chloroplast mRNA is required for or strongly stimulates its translation.

* Corresponding author. Mailing address: Dept. of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel. Phone: 972-4-8293171. Fax: 972-4-8225153. E-mail: gadis{at}tx.technion.ac.il.

dagger This paper is dedicated to Robert Drager, who passed away on 30 March 1998.

Dagger Present address: The Israeli Institute for Biological Research, P.O. Box 19, Nes-Ziona, Israel 70450.

Mol Cell Biol, August 1998, p. 4605-4611, Vol. 18, No. 8
0270-7306/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. J. Virol. Eukaryot. Cell
Microbiol. Mol. Biol. Rev. Clin. Vaccine Immunol. All ASM Journals

Copyright © 1998 by the American Society for Microbiology. All rights reserved.