Discovering how chloroplasts are made
The chloroplast is the site of photosynthesis in plants. Most of the chloroplast proteins must be imported from the cytosol. The plant physiology laboratory is interested in the import mechanism and over the years has identified and analyzed components of the chloroplast protein import machinery consisting of the translocon complexes at the outer (Toc) and inner (Tic) membranes. Many of the Toc and Tic components are essential for plant viability and have pale (eg Toc33), albino (eg Toc159) or embryo lethal (eg Toc75) phenotypes.
Chloroplasts contain lipid droplets called plastoglobules. They are involved in the lipid metabolism of the photosynthetic membrane system, the thylakoids. Plastoglobules are studded with enzymes involved in thylakoid lipid metabolism and play a role (among others) in the synthesis and accumulation of prenylquinones: tocopherol (Vitamine E), phylloquinone (Vitamine K) and plastoquinone. In the framework of the SPSW, we use mass spectrometry techniques to determine the lipidome of plastoglobules. Mass spectrometry is also an essential tool to discover the function of unknown plastoglobule enzymes by comparing the lipids in mutants to the wild type.
- Plastidial NAD-Dependent Malate Dehydrogenase: A Moonlighting Protein Involved in Early Chloroplast Development through Its Interaction with an FtsH12-FtsHi Protease Complex
Schreier, Tina B.; Clery, Antoine; Schlaefli, Michael; Galbier, Florian; Stadler, Martha; Demarsy, E; Albertini, D; Maier, BA; Kessler, F; Hortensteiner, S; Zeeman, SC; Kotting, O
PLANT CELL 30(8): 1745-1769 10.1105/tpc.18.00121 AUG 2018
- Chloroplast Biogenesis Controlled by DELLA-TOC159 Interaction in Early Plant Development
Shanmugabalaji, V; Chahtane, H; Accossato, S; Rahire, M; Gouzerh, G; Lopez-Molina, L; Kessler, F
CURRENT BIOLOGY, 28 (16):2616-+; 10.1016/j.cub.2018.06.006 AUG 20 2018
- Essential role for phytol kinase and tocopherol in tolerance to combined light and temperature stress in tomato
Spicher, Livia; Almeida, Juliana; Gutbrod, Katharina; et al.
JOURNAL OF EXPERIMENTAL BOTANY, 68 (21-22): 5845-5856 10.1093/jxb/erx356 2017
- Plastoglobuli: Plastid Microcompartments with Integrated Functions in Metabolism, Plastid Developmental Transitions, and Environmental Adaptation
van Wijk, Klaas J.; Kessler, Felix
ANNUAL REVIEW OF PLANT BIOLOGY, VOL 68, 68: 253-289 2017 (Details)
- The novel chloroplast outer membrane kinase KOC1 is a required component of the plastid protein import machinery
Zufferey, Monica; Montandon, Cyrille; Douet, Veronique; et al.
JOURNAL OF BIOLOGICAL CHEMISTRY, 292 (17): 6952-6964 APR 28 2017 (Details)
- Identification of Plastoglobules as a Site of Carotenoid Cleavage
Rottet, Sarah; Devillers, Julie; Glauser, Gaetan; et al.
FRONTIERS IN PLANT SCIENCE, 7: DEC 8 2016 (Details)
- Down-regulation of tomato PHYTOL KINASE strongly impairs tocopherol biosynthesis and affects prenyllipid metabolism in an organ-specific manner
Almeida, Juliana; Azevedo, Mariana da Silva; Spicher, Livia; et al. JOURNAL OF EXPERIMENTAL BOTANY, 67 (3): 919-934 FEB 2016 (Details)