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: A mechanism implicating plastoglobules in thylakoid disassembly during senescence and nitrogen starvation
    Author(s): Besagni, Celine; Kessler, Felix
    Source: PLANTA, 237 (2): 463-470 FEB 2013
    Document Type: Review (Details)
  • Title: Dual targeting of a mature plastoglobulin/fibrillin fusion protein to chloroplast plastoglobules and thylakoids in transplastomic tobacco plants
    Author(s): Shanmugabalaji, Venkatasalam; Besagni, Celine; Piller, Lucia Eugeni; et al.
    Source: PLANT MOLECULAR BIOLOGY, 81 (1-2): 13-25 JAN 2013
    Document Type: Article (Details)
  • Title: Chloroplast Delivery by UPS
    Author(s): Kessler, Felix
    Source: SCIENCE, 338 (6107): 622-623 NOV 2 2012
    Document Type: Editorial Material (Details)
  • Title: Fatty Acid Phytyl Ester Synthesis in Chloroplasts of Arabidopsis
    Author(s): Lippold, Felix; vom Dorp, Katharina; Abraham, Marion; et al.
    Source: PLANT CELL, 24 (5): 2001-2014 MAY 2012
    Document type: Article (Details)
  • 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)