Université de Neuchâtel

The Acidic A-Domain of Arabidopsis Toc159 Occurs as a Hyperphosphorylated Protein

Agne, Birgit ; Andrès, Charles ; Montandon, Cyril ; Christ, Bastien ; Ertan, Anouk ; Jung, Friederike ; Infanger, Sibylle ; Bischof, Sylvain ; Baginsky, Sacha ; Kessler, Felix

In: Plant Physiology, 2010, vol. 53, no. 3, p. 1016-1030

The translocon at the outer membrane of the chloroplast assists the import of a large class of preproteins with amino-terminal transit sequences. The preprotein receptors Toc159 and Toc33 in Arabidopsis (Arabidopsis thaliana) are specific for the accumulation of abundant photosynthetic proteins. The receptors are homologous GTPases known to be regulated by phosphorylation within their...

Université de Neuchâtel

The Chloroplast Import Receptor Toc90 Partially Restores the Accumulation of Toc159 Client Proteins in the Arabidopsis thaliana ppi2 Mutant

Infanger, Sibylle ; Bischof, Sylvain ; Hiltbrunner, Andreas ; Agne, Birgit ; Baginsky, Sacha ; Kessler, Felix

In: Molecular Plant, 2011, vol. 4, no. 2, p. 252–263

Successful import of hundreds of nucleus-encoded proteins is essential for chloroplast biogenesis. The import of cytosolic precursor proteins relies on the Toc- (translocon at the outer chloroplast membrane) and Tic- (translocon at the inner chloroplast membrane) complexes. In Arabidopsis thaliana, precursor recognition is mainly mediated by outer membrane receptors belonging to two...

Université de Neuchâtel

A Toc159 Import Receptor Mutant, Defective in Hydrolysis of GTP, Supports Preprotein Import into Chloroplasts

Agne, Birgit ; Infanger, Sibylle ; Wang, Fei ; Hofstetter, Valère ; Rahim, Gwendoline ; Martin, Meryll ; Lee, Dong Wook ; Hwang, Inhwan ; Schnell, Danny J. ; Kessler, Felix

In: The Journal of Biological Chemistry (JBC), 2009, vol. 284, no. 13, p. 8670-8679

The heterotrimeric Toc core complex of the chloroplast protein import apparatus contains two GTPases, Toc159 and Toc34, together with the protein-conducting channel Toc75. Toc159 and Toc34 are exposed at the chloroplast surface and function in preprotein recognition. Together, they have been shown to facilitate the import of photosynthetic proteins into chloroplasts in Arabidopsis....

Université de Neuchâtel

AtToc90, a New GTP-Binding Component of the Arabidopsis Chloroplast Protein Import Machinery

Hiltbrunner, Andreas ; Grünig, Kathrin ; Alvarez-Huerta, Mayte ; Infanger, Sibylle ; Bauer, Jörg ; Kessler, Felix

In: Plant Molecular Biology, 2004, vol. 54, p. 427 - 440

AtToc159 is a GTP-binding chloroplast protein import receptor. In vivo, atToc159 is required for massive accumulation of photosynthetic proteins during chloroplast biogenesis. Yet, in mutants lacking atToc159 photosynthetic proteins still accumulate, but at strongly reduced levels whereas non-photosynthetic proteins are imported normally: This suggests a role for the homologues of atToc159...