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Impact of reduced O-acetylserine(thiol)lyase isoform contents on potato plant metabolism.
Plant Physiol 2005; 137(3):892-900PP

Abstract

Plant cysteine (Cys) synthesis can occur in three cellular compartments: the chloroplast, cytoplasm, and mitochondrion. Cys formation is catalyzed by the enzyme O-acetylserine(thiol)lyase (OASTL) using O-acetylserine (OAS) and sulfide as substrates. To unravel the function of different isoforms of OASTL in cellular metabolism, a transgenic approach was used to down-regulate specifically the plastidial and cytosolic isoforms in potato (Solanum tuberosum). This approach resulted in decreased RNA, protein, and enzymatic activity levels. Intriguingly, H(2)S-releasing capacity was also reduced in these lines. Unexpectedly, the thiol levels in the transgenic lines were, regardless of the selected OASTL isoform, significantly elevated. Furthermore, levels of metabolites such as serine, OAS, methionine, threonine, isoleucine, and lysine also increased in the investigated transgenic lines. This indicates that higher Cys levels might influence methionine synthesis and subsequently pathway-related amino acids. The increase of serine and OAS points to suboptimal Cys synthesis in transgenic plants. Taking these findings together, it can be assumed that excess OASTL activity regulates not only Cys de novo synthesis but also its homeostasis. A model for the regulation of Cys levels in plants is proposed.

Authors+Show Affiliations

Institut für Botanik, Universität Hannover, D-30419 Hannover, Germany.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

15728339

Citation

Riemenschneider, Anja, et al. "Impact of Reduced O-acetylserine(thiol)lyase Isoform Contents On Potato Plant Metabolism." Plant Physiology, vol. 137, no. 3, 2005, pp. 892-900.
Riemenschneider A, Riedel K, Hoefgen R, et al. Impact of reduced O-acetylserine(thiol)lyase isoform contents on potato plant metabolism. Plant Physiol. 2005;137(3):892-900.
Riemenschneider, A., Riedel, K., Hoefgen, R., Papenbrock, J., & Hesse, H. (2005). Impact of reduced O-acetylserine(thiol)lyase isoform contents on potato plant metabolism. Plant Physiology, 137(3), pp. 892-900.
Riemenschneider A, et al. Impact of Reduced O-acetylserine(thiol)lyase Isoform Contents On Potato Plant Metabolism. Plant Physiol. 2005;137(3):892-900. PubMed PMID: 15728339.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Impact of reduced O-acetylserine(thiol)lyase isoform contents on potato plant metabolism. AU - Riemenschneider,Anja, AU - Riedel,Kerstin, AU - Hoefgen,Rainer, AU - Papenbrock,Jutta, AU - Hesse,Holger, Y1 - 2005/02/22/ PY - 2005/2/25/pubmed PY - 2005/6/21/medline PY - 2005/2/25/entrez SP - 892 EP - 900 JF - Plant physiology JO - Plant Physiol. VL - 137 IS - 3 N2 - Plant cysteine (Cys) synthesis can occur in three cellular compartments: the chloroplast, cytoplasm, and mitochondrion. Cys formation is catalyzed by the enzyme O-acetylserine(thiol)lyase (OASTL) using O-acetylserine (OAS) and sulfide as substrates. To unravel the function of different isoforms of OASTL in cellular metabolism, a transgenic approach was used to down-regulate specifically the plastidial and cytosolic isoforms in potato (Solanum tuberosum). This approach resulted in decreased RNA, protein, and enzymatic activity levels. Intriguingly, H(2)S-releasing capacity was also reduced in these lines. Unexpectedly, the thiol levels in the transgenic lines were, regardless of the selected OASTL isoform, significantly elevated. Furthermore, levels of metabolites such as serine, OAS, methionine, threonine, isoleucine, and lysine also increased in the investigated transgenic lines. This indicates that higher Cys levels might influence methionine synthesis and subsequently pathway-related amino acids. The increase of serine and OAS points to suboptimal Cys synthesis in transgenic plants. Taking these findings together, it can be assumed that excess OASTL activity regulates not only Cys de novo synthesis but also its homeostasis. A model for the regulation of Cys levels in plants is proposed. SN - 0032-0889 UR - https://www.unboundmedicine.com/medline/citation/15728339/Impact_of_reduced_O_acetylserine_thiol_lyase_isoform_contents_on_potato_plant_metabolism_ L2 - http://www.plantphysiol.org/cgi/pmidlookup?view=long&pmid=15728339 DB - PRIME DP - Unbound Medicine ER -