Research profile Prof. Dr. Christian Ungermann

The Ungermann group studies the molecular mechanisms of endosome, lysosome and autophagosome biogenesis. Endosomes provide a central link between the plasma membrane and the lysosome as the cell's digestive organelle. Autophagosomes are formed to degrade proteins or entire organelles to recycle their components. We combine cell biological methods with in vitro reconstitution on liposomes to understand the function of proteins and protein complexes involved, and thus their function in the development of disease.

Research topics

• Molecular mechanisms of endosomal maturation and fusion
• Regulation of autophagosome and lysosome biogenesis
• Endosomal signal transduction 

Model systems

• Saccharomyces cervisae (Baker`s yeast)
• Reconstituted membrane systems
• Insect cells and in cooperation Drosophila melanogaster

Methods

• Purification of proteins and large protein complexes
• Fluorescence microscopy
• Enzymatic activity assays
• Reconstitution of membrane proteins into liposomes
• Membrane fusion assays

Selected publications

• Langemeyer L, Borchers A-C, Herrmann E, Füllbrunn N, Han Y, Perz A, Auffarth K, Kümmel D, Ungermann C (2020):  A conserved and regulated mechanism drives endosomal Rab transition. Elife 9: e56090.
• Chen Z, Malia PC, Hatakeyama R, Nicastro R, Hu Z, Péli-Gulli M-P, Gao J, Nishimura T, Eskes E, Stefan CJ, Winderickx J, Dengjel J, De Virgilio C, & Ungermann C (2021):  TORC1 Determines Fab1 Lipid Kinase Function at Signaling Endosomes and Vacuoles. Curr Biol 31: 297-309.
• Gao J, Langemeyer L, Kümmel D, Reggiori F, & Ungermann C (2018):  Molecular mechanism to target the endosomal Mon1-Ccz1 GEF complex to the pre-autophagosomal structure. Elife 7: e31145.