Back to Search
Start Over
Suppressing Farnesyl Diphosphate Synthase Alters Chloroplast Development and Triggers Sterol-Dependent Induction of Jasmonate- and Fe-Related Responses
- Source :
- Digital.CSIC. Repositorio Institucional del CSIC, instname, Dipòsit Digital de la UB, Universidad de Barcelona, Recercat. Dipósit de la Recerca de Catalunya
- Publication Year :
- 2016
- Publisher :
- Oxford University Press (OUP), 2016.
-
Abstract
- Farnesyl diphosphate synthase (FPS) catalyzes the synthesis of farnesyl diphosphate from isopentenyl diphosphate and dimethylallyl diphosphate. Arabidopsis (Arabidopsis thaliana) contains two genes (FPS1 and FPS2) encoding FPS. Single fps1 and fps2 knockout mutants are phenotypically indistinguishable from wild-type plants, while fps1/fps2 double mutants are embryo lethal. To assess the effect of FPS down-regulation at postembryonic developmental stages, we generated Arabidopsis conditional knockdown mutants expressing artificial microRNAs devised to simultaneously silence both FPS genes. Induction of silencing from germination rapidly caused chlorosis and a strong developmental phenotype that led to seedling lethality. However, silencing of FPS after seed germination resulted in a slight developmental delay only, although leaves and cotyledons continued to show chlorosis and altered chloroplasts. Metabolomic analyses also revealed drastic changes in the profile of sterols, ubiquinones, and plastidial isoprenoids. RNA sequencing and reverse transcription-quantitative polymerase chain reaction transcriptomic analysis showed that a reduction in FPS activity levels triggers the misregulation of genes involved in biotic and abiotic stress responses, the most prominent one being the rapid induction of a set of genes related to the jasmonic acid pathway. Down-regulation of FPS also triggered an iron-deficiency transcriptional response that is consistent with the iron-deficient phenotype observed in FPS-silenced plants. The specific inhibition of the sterol biosynthesis pathway by chemical and genetic blockage mimicked these transcriptional responses, indicating that sterol depletion is the primary cause of the observed alterations. Our results highlight the importance of sterol homeostasis for normal chloroplast development and function and reveal important clues about how isoprenoid and sterol metabolism is integrated within plant physiology and development.<br />We acknowledge financial support from the Spanish Ministry of Economy and Competitiveness through the “Severo Ochoa Programme for Centres of Excellence in R&D” 2016-2019 (SEV-2015-0533). This work was supported by the Spanish Government (grant nos. BIO2009–06984 and AGL2013–43522-R to A.F.) and the Generalitat de Catalunya (grant no. 2014SGR–1434).
- Subjects :
- 0106 biological sciences
0301 basic medicine
Chloroplasts
Physiology
Mutant
Arabidopsis
Fitosterols
Homeòstasi
Plantes
Plant Science
01 natural sciences
chemistry.chemical_compound
Gene Expression Regulation, Plant
Homeostasis
Arabidopsis thaliana
Jasmonate
Microscopy, Confocal
biology
Reverse Transcriptase Polymerase Chain Reaction
Jasmonic acid
food and beverages
Phytosterols
Sterol homeostasis
Geranyltranstransferase
Articles
Plants
Plants, Genetically Modified
Sterols
Biochemistry
embryonic structures
lipids (amino acids, peptides, and proteins)
animal structures
Iron
Blotting, Western
Cyclopentanes
03 medical and health sciences
Farnesyl diphosphate synthase
Microscopy, Electron, Transmission
Genetics
Gene Silencing
Oxylipins
Arabidopsis Proteins
organic chemicals
Gene Expression Profiling
biology.organism_classification
Sterol
Gene Ontology
030104 developmental biology
chemistry
Mutation
biology.protein
010606 plant biology & botany
Subjects
Details
- ISSN :
- 15322548 and 00320889
- Volume :
- 172
- Database :
- OpenAIRE
- Journal :
- Plant Physiology
- Accession number :
- edsair.doi.dedup.....c3833be6f53043ace05a83d62120fd64