Discovering how chloroplasts are made

Chloroplasts and Photosynthesis

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.

Research topics

  • Chloroplast Biogenesis

  • Chloroplast Protein Import

  • Chloroplast Lipid Droplets

Interdisciplinary

  • Analytical chemistry of natural products

  • Systems Biology

Contact Person

Prof. Dr. Felix Kessler

University of Neuchâtel
Institute of Biology
Website
felix.kessler-at-unine.ch
+41 (0)32 718 22 92


Recent publications

  • Title: STAY-GREEN and Chlorophyll Catabolic Enzymes Interact at Light-Harvesting Complex II for Chlorophyll Detoxification during Leaf Senescence in Arabidopsis
    Author(s): Sakuraba, Yasuhito; Schelbert, Silvia; Park, So-Yon; et al.
    Source: PLANT CELL, 24 (2): 507-518 FEB 2012
    Document type: Article (Details)
  • Title: Plastid lipid droplets at the crossroads of prenylquinone metabolism
    Author(s): Piller, Lucia Eugeni; Abraham, Marion; Doermann, Peter; et al.
    Source: JOURNAL OF EXPERIMENTAL BOTANY, 63 (4): 1609-1618 FEB 2012
    Document type: Review (Details)
  • Chloroplast lipid droplet type II NAD(P)H quinone oxidoreductase is essential for prenylquinone metabolism and vitamin K(1) accumulation
    Piller, Lucia Eugeni; Besagni, Celine; Ksas, Brigitte; et al.
    PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 108 (34): 14354-14359 AUG 23 2011 (Details)
  • A novel method for prenylquinone profiling in plant tissues by ultra-high pressure liquid chromatography-mass spectrometry
    Martinis, Jacopo; Kessler, Felix; Glauser, Gaetan
    PLANT METHODS, 7 (): JUL 21 2011 (Details)
  • The Chloroplast Import Receptor Toc90 Partially Restores the Accumulation of Toc159 Client Proteins in the Arabidopsis thaliana ppi2 Mutant
    Infanger, S; Bischof, S; Hiltbrunner, A; et al.
    MOLECULAR PLANT 4 (2): 252-263 MAR 2011 (Details)