Plant Physiol. Drug Metab Dispos
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

Plant Physiology Preview
Published on August 27, 2008; 10.1104/pp.108.125237

OPEN ACCESS ARTICLE
This Article
Free via Open Access: OA
Right arrow Full Text (Plant Physiology Preview (PDF))
Right arrow Supplemental Data
Right arrowOA All Versions of this Article:
148/2/1055    most recent
pp.108.125237v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Web of Science (2)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Haas, F. H.
Right arrow Articles by Hell, R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Haas, F. H.
Right arrow Articles by Hell, R.
Agricola
Right arrow Articles by Haas, F. H.
Right arrow Articles by Hell, R.

Received June 24, 2008
Accepted August 25, 2008

Mitochondrial serine acetyltransferase functions as pacemaker of cysteine synthesis in plant cells

Florian H. Haas , Corinna Heeg , Rafael Queiroz , Andrea Bauer , Markus Wirtz , and Rudiger Hell *

Heidelberg Institute for Plant Sciences (HIP), Heidelberg University, Im Neuenheimer Feld 360, 69120 Heidelberg, Germany; German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, 69120 Heidelberg, Germany

* Corresponding author; email: rhell{at}hip.uni-heidelberg.de.

Cysteine synthesis in plants is carried out by two sequential reactions catalyzed by the rate-limiting enzyme serine acetyltransferase (SAT) and excess amounts of O-acetylserine(thiol)lyase (OAS-TL). Why these reactions occur in plastids, mitochondria and cytosol of plants remained unclear. Expression of artificial micro RNA (amiRNA) against Sat3 encoding mitochondrial SAT3 in transgenic Arabidopsis thaliana plants demonstrates that mitochondria are the most important compartment for synthesis of O-acetylserine (OAS), the precursor of cysteine. Reduction of RNA levels, protein contents, SAT enzymatic activity and phenotype strongly correlate in independent amiSAT3 lines and cause significantly retarded growth. The expression of the other four Sat genes in the Arabidopsis genome are not affected by amiRNA-SAT3 according to quantitative real time PCR and microarray analyses. Application of radiolabeled serine to leaf pieces reveales severely reduced incorporation rates into cysteine and even more so into glutathione. Accordingly steady-state levels of OAS are 4-fold reduced. Decrease of sulfate reduction related genes is accompanied by accumulation of sulfate in amiSAT3 lines. The results unequivocally show that mitochondria provide the bulk of OAS in the plant cell and are the likely site of flux regulation. Together with recent data [Heeg et al. (2008) Plant Cell 20: 168] the cytosol appears as major site of cysteine synthesis while plastids contribute reduced sulfur as sulfide. Thus, cysteine synthesis in plants is significantly different from that in non-photosynthetic eukaryotes at the cellular level.




This article has been cited by other articles:


Home page
 Mol PlantHome page
G. Queval, D. Thominet, H. Vanacker, M. Miginiac-Maslow, B. Gakiere, and G. Noctor
H2O2-Activated Up-Regulation of Glutathione in Arabidopsis Involves Induction of Genes Encoding Enzymes Involved in Cysteine Synthesis in the Chloroplast
Mol Plant, March 1, 2009; 2(2): 344 - 356.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
ASPB Publications PLANT PHYSIOLOGY® THE PLANT CELL
Copyright © 2008 by the American Society of Plant Biologists