Group Bachmair

N-degron pathways

Group Leader

Andreas Bachmair

After his PhD in Biochemistry in Vienna, Andreas Bachmair did postdoctoral research at the MIT in Cambridge, USA, and at the MPI for Plant Breeding Research in Germany. 1991-2002 he was Assistant Professor at the University of Vienna, 2002-2008 Group Leader at the MPI for Plant Breeding Research, and in 2009 back to the University of Vienna, first as Associate Professor and since 2019 full Professor at the Max Perutz Labs.

Projects within consortium

The amino terminus of a protein is a determinant of its half-life. Using the model plant Arabidopsis thaliana, we investigate how proteins are turned over that have N-terminal amino acids with bulky side chain. We are interested in pathway components and in signal transduction cascades that depend on these pathways. Particular focus lies on N-terminal Leu, because for these proteins, the degradation path is currently uncharacterized.

The amino terminus is an important determinant of a protein´s half-life. This pertains not only to primary translation products, but even more to products of proteolytic processing, generated by over five hundred proteases encoded in every metazoan genome. Many of the neo-N-termini generated by these latter enzymes are signals that shorten the protein half-life, channeling affected proteins into degradation routes called N-degron pathways. Unacetylated first amino acids can act as degradation signals if they have either a hydrophobic, or a basic side chain. Degradation of proteins with basic first residue is mechanistically similar in animals and in plants, and participates in oxygen sensing. In contrast, turnover of proteins with hydrophobic N-terminal residues uses pathways that differ between animals and plants. Of particular interest to us is the degradation route for plant proteins with aliphatic hydrophobic amino-terminal residues such as Leu, because it is still uncharacterized. Our preliminary data suggest that both the ubiquitin-proteasome system, and autophagy participate in degradation. We are studying the pathway components using model substrates and a broad array of genetic, biochemical and cell biology methods. We also want to identify signal transduction cascades that utilize these pathways in stress response and development.

Accumulation of a GUS protein with N-terminal Leu in prt (proteolysis) mutant seedlings can be visualized by increased conversion of a chromogenic substrate into a blue precipitate.

Project members

  • Postdoc

    Nikola Winter

    SFB Member

  • Master student

    Katrin Rose

    Associated

Targeted Protein Degradation related publications by Group Bachmair

  • 2019 The Scope, Functions, and Dynamics of Posttranslational Protein Modifications Annu. Rev. Plant Biol. Millar AH, Heazlewood JL, Giglione C, Holdsworth MJ, Bachmair A, Schulze WX Go to publication →
  • 2019 Distinct branches of the N-end rule pathway modulate the plant immune response New Phytol. Vicente J, Mendiondo GM, Pauwels J, Pastor V, Izquierdo Y, Naumann C, Movahedi M, Rooney D, Gibbs DJ, Smart K, Bachmair A, Gray JE, Dissmeyer N, Castresana C, Ray RV, Gevaert K, Holdsworth MJ Go to publication →
  • 2018 SUMO chain formation relies on the amino-terminal region of SUMO conjugating enzyme and has dedicated substrates in plants Biochemical J. Tomanov, K., Nehlin, L., Ziba, I., Bachmair, A. Go to publication →
  • 2014 The eukaryotic N-end rule pathway: conserved mechanisms and diverse functions Trends in Cell Biol. Gibbs DJ, Bacardit J, Bachmair A, Holdsworth MJ Go to publication →
  • 2014 Nitric oxide sensing in plants is mediated by proteolytic control of group VII ERF transcription factors Mol. Cell Gibbs DJ, Md Isa N, Movahedi M, Lozano-Juste J, Mendiondo GM, Berckhan S, Marín-de la Rosa N, Vicente Conde J, Sousa Correia C, Pearce SP, Bassel GW, Hamali B, Talloji P, Tomé DF, Coego A, Beynon J, Alabadí D, Bachmair A, León J, Gray JE, Theodoulou FL, Holdsworth MJ Go to publication →