A5030250862- Photosynthetic Processes and Mechanisms
- Synthesis and Biological Activity
- Plant Stress Responses and Tolerance
- Chemical synthesis and alkaloids
- Plant Gene Expression Analysis
- CRISPR and Genetic Engineering
- Plant Molecular Biology Research
- Genetically Modified Organisms Research
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Algal biology and biofuel production
- International Maritime Law Issues
- Human Rights and Development
- Genetic and Environmental Crop Studies
- Marine Sponges and Natural Products
- Lipid metabolism and biosynthesis
- Genetic Mapping and Diversity in Plants and Animals
- Agricultural Innovations and Practices
- Legume Nitrogen Fixing Symbiosis
- Legal Issues in South Africa
- Genomics and Phylogenetic Studies
- Plant tissue culture and regeneration
- Plant nutrient uptake and metabolism
- Plant Diversity and Evolution
- Microbial Natural Products and Biosynthesis
University of Zurich
2011-2024
Federal Office for Agriculture
2016-2024
Federal Department of Economic Affairs, Education and Research
2023
University of Cambridge
2011-2018
World Economic Forum
2016
Centre National de la Recherche Scientifique
2007-2012
Institut de Chimie des Substances Naturelles
2010-2012
Universität Innsbruck
2005-2011
Harvard University
2008-2010
Université Claude Bernard Lyon 1
2005-2008
Abstract During leaf senescence, chlorophyll is removed from thylakoid membranes and converted in a multistep pathway to colorless breakdown products that are stored vacuoles. Dephytylation, an early step of this pathway, increases water solubility the products. It widely accepted into pheophorbide via chlorophyllide. However, chlorophyllase, which converts chlorophyllide, was found not be essential for dephytylation Arabidopsis thaliana. Here, we identify pheophytinase (PPH),...
Abstract During senescence, chlorophyll (chl) is metabolized to colorless nonfluorescent chl catabolites (NCCs). A central reaction of the breakdown pathway ring cleavage pheophorbide (pheide) a primary fluorescent catabolite. Two enzymes catalyze this reaction, pheide oxygenase (PAO) and red catabolite reductase. Five NCCs three (FCCs) accumulated during dark-induced in Arabidopsis (Arabidopsis thaliana). Three these one FCC (primary catabolite-1) were identical known from canola (Brassica...
Abstract A central reaction of chlorophyll breakdown, porphyrin ring opening pheophorbide a to the primary fluorescent catabolite (pFCC), requires oxygenase (PAO) and red reductase (RCCR), with (RCC) as presumably PAO-bound intermediate. In subsequent steps, pFCC is converted different catabolites (FCCs) nonfluorescent (NCCs). Here, we show that RCCR-deficient Arabidopsis thaliana accumulates RCC three RCC-like pigments during senescence, well FCCs NCCs. We also stereospecificity RCCR...
A key gene involved in plant senescence, mutations of which partially disable chlorophyll catabolism and confer stay-green leaf cotyledon phenotypes, has been identified Pisum sativum , Arabidopsis thaliana Festuca pratensis by using classical molecular genetics comparative genomics. locus F. is syntenically equivalent to a similar on rice chromosome 9. Functional testing homolog the candidate revealed (i) senescence-associated expression (ii) phenotype after RNA interference silencing....
With at least 60 independent origins spanning monocotyledons and dicotyledons, the C4 photosynthetic pathway represents one of most remarkable examples convergent evolution. The recurrent evolution this highly complex trait involving alterations to leaf anatomy, cell biology biochemistry allows an increase in productivity by ∼50% tropical subtropical areas. extent which separate lineages plants use same genetic networks maintain photosynthesis is unknown. We developed a new informatics...
A pair of GOLDEN2-LIKE transcription factors is required for normal chloroplast development in land plant species that encompass the range from bryophytes to angiosperms. In C(4) maize, compartmentalized function two GLK genes bundle sheath and mesophyll cells regulates dimorphic differentiation, whereas C(3) plants Physcomitrella patens Arabidopsis thaliana act redundantly all photosynthetic cells. To assess whether cell-specific unique we analyzed gene expression patterns monocot Sorghum...
Abstract Gluconeogenesis is a fundamental metabolic process that allows organisms to make sugars from non-carbohydrate stores such as lipids and protein. In eukaryotes only one gluconeogenic route has been described organic acid intermediates this relies on the enzyme phospho enol pyruvate carboxykinase (PCK). Here we show two routes exist in Arabidopsis , second uses pyruvate, orthophosphate dikinase (PPDK). critical fuel transition seed seedling. pck1 ppdk mutants are compromised...
Chlorophyll degradation is the most obvious hallmark of leaf senescence. Phyllobilins, linear tetrapyrroles that are derived from opening chlorin macrocycle by Rieske-type oxygenase PHEOPHORBIDE a OXYGENASE (PAO), end products chlorophyll degradation. Phyllobilins carry defined modifications at several peripheral positions within tetrapyrrole backbone. While these species-specific, hydroxylation C32 position commonly found in all species analyzed to date. We demonstrate this occurs senescent...
• The staygreen (SGR) gene encodes a chloroplast-targeted protein which promotes chlorophyll degradation via disruption of light-harvesting complexes (LHCs). Over-expression SGR in Arabidopsis (SGR-OX) Columbia-0 (Col-0) background caused spontaneous necrotic flecking. To relate this to the hypersensitive response (HR), Col-0, SGR-OX and RNAi (SGRi) lines were challenged with Pseudomonas syringae pv tomato (Pst) encoding avirulence avrRpm1. Increased decreased expression, respectively,...
Summary Leaves of angiosperms are made up multiple distinct cell types. While the function mesophyll cells, guard phloem companion cells and sieve elements clearly described, this is not case for bundle sheath ( BS ). To provide insight into role in C 3 species A rabidopsis thaliana , we labelled ribosomes type with a FLAG tag. We then used immunocapture to isolate these ribosomes, followed by sequencing resident m RNA s. This showed that 5% genes specific splice forms 15% were...
During leaf senescence, chlorophyll (Chl) is broken down to nonfluorescent catabolites (NCCs). These arise from intermediary fluorescent (FCCs) by an acid-catalyzed isomerization inside the vacuole. The chemical structures of NCCs Arabidopsis (Arabidopsis thaliana) indicate presence enzyme activity that demethylates C132-carboxymethyl group present at isocyclic ring Chl. Here, we identified this as methylesterase family member 16 (MES16; At4g16690). mes16 leaves exhibited a strong...
C4 photosynthesis is a complex phenotype that allows more efficient carbon capture than the ancestral C3 pathway. In leaves of species, hundreds transcripts increase in abundance compared with relatives and become restricted to mesophyll (M) or bundle sheath (BS) cells. However, no mechanism has been reported regulates compartmentation multiple enzymes M BS We examined mechanisms regulating CARBONIC ANHYDRASE4 (CA4) Gynandropsis gynandra. Increased directed by both promoter region introns G....
Anyone familiar with modern biology may find peculiar the ongoing international debates on legal status of "Digital Sequence Information" (DSI). Indeed, a large majority recent advances in biology, medicine or agriculture were achieved by sharing and mining freely accessible sequencing data. It is most probably because tremendous success genomics synthetic that concerns raised about possible fair equitable ways The DSI concept relatively new all concerned parties agreed upon need for clear...
Chlorophyll degradation is one of the most visible signs leaf senescence. During senescence, chlorophyll degraded in multistep pheophorbide a oxygenase (PAO)/phyllobilin pathway. This pathway tightly regulated at transcriptional level, allowing coordinated and efficient remobilization nitrogen toward sink organs. Using combination transcriptome metabolite analyses during dark-induced senescence Arabidopsis (Arabidopsis thaliana) mutants deficient key steps PAO/phyllobilin pathway, we show an...
Abstract Genebanking, the process of preserving genetic resources, is a central practice in modern management crop genetics, especially for species used food and agriculture. Closely interrelated networks local, national global actors are responsible ex situ conservation. They all seek to make plant resources accessible now face new challenges arising from digitisation. Plant sciences entering postgenomic era, moving fast initially providing single reference genome each (genomics),...
Highlights•Strigolactones induce the presence of hypodermal passage cells (HPC) in root•ABA, ethylene, auxin, and karrikins negatively regulate density HPC•HPC is regulated by KAI2/MAX2 signaling pathway•Hormonal cross talk regulates HPC therefore hypodermis permeabilitySummaryThe majority land plants have two suberized root barriers: endodermis (exodermis). Both barriers bear non-suberized that are thought to water nutrient exchange between soil. We learned a lot about endodermal cells,...