Ruprecht-Karls-Universität Heidelberg
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Askani, Jana Christin

Jana Christin Askani

+49 6221 54-5614
Prof. Dr. Karin Schumacher
Centre for Organismal Studies (COS)

Field of interest:

Vacuoles are essential for the proper functionality of plant cells and thereby contributing to the success of land plants. In lytic vacuoles, degradation processes of cell components occur, essential nutrients and metabolites are stored, harmful molecules are detoxified and through osmotic water uptake vacuoles generate the necessary turgor pressure for plant growth. These various functions of a plant vacuole require massive fluxes of molecules across the vacuolar membrane. In order to energize the necessary transport processes, two proton pumps exist at the tonoplast: the vacuolar H+- pyrophosphatase (V-PPase) and the vacuolar H+-adenosinetriphosphatase (V-ATPase).
The subcellular localization of the V-ATPase is determined by the incorporation of the membrane-integral VHA-a subunit at the Endoplasmic Reticulum (ER). The V-ATPase is targeted to the trans-Golgi network (TGN)/early endosome (EE), if the isoform VHA-a1 is assembled into the VO complex. Whereas the integrated isoforms VHA-a2 and VHA-a3 localize the V-ATPase to the tonoplast.
By investigating the different transport routes of the proton pumps, it was found that the V-PPase and the V-ATPase complexes containing the VHA-a2/a3 isoforms are transported from the ER directly to the tonoplast via provacuoles. With the identification of a Golgi-independent transport route from the ER directly to the tonoplast, special interest lies in the enlightening on how VHA-a3 containing V-ATPases are sorted into specific subdomains of the ER and how provacuoles constrict from the ER and fuse with other vacuolar membranes.

Curriculum Vitae

Prize for Best Poster Presentation
Bristol-Kyoto-Heidelberg workshop, February 2017, Bristol, UK
provided by the New Phytologist Trust

Prize for Best Talk
30th Conference of Molecular Biology of Plants,
Dabringhausen February 2017

Post Graduate Education
HBIGS International Graduate School of
Molecular & Cellular Biology

University education
Molecular Biosciences,
Major Molecular Plant Sciences,
University Heidelberg, Master of Science

University education
Biological Sciences
University of Konstanz, Bachelor of Science


BRI1 controls vascular cell fate in the Arabidopsis root through RLP44 and phytosulfokine signaling. (2018) Holzwart E, Huerta AI, Glöckner N, Garnelo Gómez B, Wanke F, Augustin S, Askani JC, Schürholz AK, Harter K, Wolf S Proc Natl Acad Sci U S A, doi: 10.1073/pnas.1814434115

Phosphoinositides control the localization of HOPS subunit VPS41, which together with VPS33 mediates vacuole fusion in plants. (2018) Brillada C, Zheng J, Krüger F, Rovira-Diaz E, Askani JC, Schumacher K, Rojas-Pierce M Proc Natl Acad Sci U S A, doi: 10.1073/pnas.1807763115

Distinct sets of tethering complexes, SNARE complexes, and Rab GTPases mediate membrane fusion at the vacuole in Arabidopsis (2018) Takemoto K, Ebine K, Askani JA, Krüger F, Gonzalez ZA,Ito E, Goh T, Schumacher K, Nakano A, Ueda T Proc Natl Acad Sci U S A,