Published online 18 January 2006
Article |
Sub-plastidial localization of two different phage-type RNA polymerases in spinach chloroplasts
Laboratoire Plastes et différenciation cellulaire, Université Joseph Fourier and Centre National de la Recherche Scientifique B.P. 53, 38041 Grenoble, France
*To whom correspondence should be addressed. Tel: +33 04 76 63 57 44; Fax: +33 04 76 63 55 86; Email: silva.lerbs-mache{at}ujf-grenoble.fr
Received November 23, 2005. Revised December 23, 2005. Accepted January 3, 2005.
Plant plastids contain a circular genome of 
150 kb organized into 35 transcription units. The plastid genome is organized into nucleoids and attached to plastid membranes. This relatively small genome is transcribed by at least two different RNA polymerases, one being of the prokaryotic type and plastid-encoded (PEP), the other one being of the phage-type and nucleus-encoded (NEP). The presumed localization of a second phage-type RNA polymerase in plastids is still questionable. There is strong evidence for a sequential action of NEP and PEP enzymes during plant development attributing a prevailing role of NEP during early plant and plastid development, although NEP is present in mature chloroplasts. In the present paper, we have analysed two different NEP enzymes from spinach with respect to subcellular and intra-plastidial localization in mature chloroplasts with the help of specific antibodies. Results show the presence of the two different NEP enzymes in mature chloroplasts. Both enzymes are entirely membrane bound but, unlike previously thought, this membrane binding is not mediated via DNA. This finding indicates that NEP enzymes are not found as elongating transcription complexes on the template DNA in mature chloroplasts and raises the question of their function in mature chloroplasts.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  J. Azevedo, F. Courtois, M.-A. Hakimi, E. Demarsy, T. Lagrange, J.-P. Alcaraz, P. Jaiswal, L. Marechal-Drouard, and S. Lerbs-Mache Intraplastidial trafficking of a phage-type RNA polymerase is mediated by a thylakoid RING-H2 protein PNAS, July 1, 2008; 105(26): 9123 - 9128. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Swiatecka-Hagenbruch, C. Emanuel, B. Hedtke, K. Liere, and T. Borner Impaired function of the phage-type RNA polymerase RpoTp in transcription of chloroplast genes is compensated by a second phage-type RNA polymerase Nucleic Acids Res., February 11, 2008; 36(3): 785 - 792. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. Kuhn, A.-V. Bohne, K. Liere, A. Weihe, and T. Borner Arabidopsis Phage-Type RNA Polymerases: Accurate in Vitro Transcription of Organellar Genes PLANT CELL, March 1, 2007; 19(3): 959 - 971. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Li and S. Horvath Network neighborhood analysis with the multi-node topological overlap measure Bioinformatics, January 15, 2007; 23(2): 222 - 231. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Demarsy, F. Courtois, J. Azevedo, L. Buhot, and S. Lerbs-Mache Building Up of the Plastid Transcriptional Machinery during Germination and Early Plant Development Plant Physiology, November 1, 2006; 142(3): 993 - 1003. [Abstract] [Full Text] [PDF]
|
|