Schluter U.,Friedrich - Alexander - University, Erlangen - Nuremberg |
Mascher M.,Leibniz Institute of Plant Genetics and Crop Plant Research |
Colmsee C.,Leibniz Institute of Plant Genetics and Crop Plant Research |
Scholz U.,Leibniz Institute of Plant Genetics and Crop Plant Research |
And 3 more authors.
Plant Physiology | Year: 2012
Crop plant development is strongly dependent on the availability of nitrogen (N) in the soil and the efficiency of N utilization for biomass production and yield. However, knowledge about molecular responses to N deprivation derives mainly from the study of model species. In this article, the metabolic adaptation of source leaves to low N was analyzed in maize (Zea mays) seedlings by parallel measurements of transcriptome and metabolome profiling. Inbred lines A188 and B73 were cultivated under sufficient (15 mM) or limiting (0.15 mM) nitrate supply for up to 30 d. Limited availability of N caused strong shifts in the metabolite profile of leaves. The transcriptome was less affected by the N stress but showed strong genotype- and age-dependent patterns. N starvation initiated the selective down-regulation of processes involved in nitrate reduction and amino acid assimilation; ammonium assimilation-related transcripts, on the other hand, were not influenced. Carbon assimilation-related transcripts were characterized by high transcriptional coordination and general down-regulation under low-N conditions. N deprivation caused a slight accumulation of starch but also directed increased amounts of carbohydrates into the cell wall and secondary metabolites. The decrease in N availability also resulted in accumulation of phosphate and strong down-regulation of genes usually involved in phosphate starvation response, underlining the great importance of phosphate homeostasis control under stress conditions. © 2012 American Society of Plant Biologists.
Richter A.S.,Humboldt University of Berlin |
Peter E.,Humboldt University of Berlin |
Peter E.,metanomics GmbH |
Rothbart M.,Humboldt University of Berlin |
And 4 more authors.
Plant Physiology | Year: 2013
The NADPH-dependent thioredoxin reductase C (NTRC) is involved in redox-related regulatory processes in chloroplasts and nonphotosynthetic active plastids. Together with 2-cysteine peroxiredoxin, it forms a two-component peroxide-detoxifying system that acts as a reductant under stress conditions. NTRC stimulates in vitro activity of magnesium protoporphyrin IX monomethylester (MgPMME) cyclase, most likely by scavenging peroxides. Reexamination of tetrapyrrole intermediate levels of the Arabidopsis (Arabidopsis thaliana) knockout ntrc reveals lower magnesium protoporphyrin IX (MgP) and MgPMME steadystate levels, the substrate and the product of MgP methyltransferase (CHLM) preceding MgPMME cyclase, while MgP strongly accumulates in mutant leaves after 5-aminolevulinic acid feeding. The ntrc mutant has a reduced capacity to synthesize 5-aminolevulinic acid and reduced CHLM activity compared with the wild type. Although transcript levels of genes involved in chlorophyll biosynthesis are not significantly altered in 2-week-old ntrc seedlings, the contents of glutamyl-transfer RNA reductase1 (GluTR1) and CHLM are reduced. Bimolecular fluorescence complementation assay confirms a physical interaction of NTRC with GluTR1 and CHLM. While ntrc contains partly oxidized CHLM, the wild type has only reduced CHLM. As NTRC also stimulates CHLM activity in vitro, it is proposed that NTRC has a regulatory impact on the redox status of conserved cysteine residues of CHLM. It is hypothesized that a deficiency of NTRC leads to a lower capacity to reduce cysteine residues of GluTR1 and CHLM, affecting the stability and, thereby, altering the activity in the entire tetrapyrrole synthesis pathway. © 2013 American Society of Plant Biologists. All Rights Reserved.
French Institute of Health, Medical Research and Metanomics GmbH | Date: 2013-09-30
The present invention relates to the field of diagnostic measures. Specifically, it contemplates a method for assessing whether gastric bypass therapy was successful in a subject, a method of predicting whether gastric bypass therapy will be beneficial for a subject in need thereof, and a method of diagnosing whether a supportive therapy accompanying gastric bypass has beneficial effects on a subject in need thereof. Further provided are diagnostic methods for diabetes and body lean mass. Furthermore, the invention relates to a method for identifying a treatment against diabetes and/or obesity.
Metanomics GmbH | Date: 2011-09-22
The present invention relates to a process for the production of fine chemicals in a microorganism, a plant cell, a plant, a plant tissue or in one or more parts thereof. The present invention relates further to a process for the control of the production of fine chemicals in a microorganism, a plant cell, a plant, a plant tissue or in one or more parts thereof. The invention furthermore relates to nucleic acid molecules, polypeptides, nucleic acid constructs, vectors, antisense molecules, antibodies, host cells, plant tissue, propagation material, harvested material, plants, microorganisms as well as agricultural compositions and to their use.
Metanomics GmbH | Date: 2011-06-07
The present invention relates to a process for the increase in yield in a plant organism by reducing gene expression. The invention furthermore relates to nucleic acid molecules, polypeptides, nucleic acid constructs, vectors, antisense molecules, antibodies, host cells, plant tissue, propagation material, harvested material and plants.