Publications in Scientific Journals:
A. Anderluh, E. Klotzsch, A. Reismann, M. Brameshuber, O. Kudlacek, A. Newman, H. Sitte, G. Schütz:
"Single Molecule Analysis Reveals Coexistence of Stable Serotonin Transporter Monomers and Oligomers in the Live Cell Plasma Membrane";
The human serotonin transporter (hSERT) is responsible
for the termination of synaptic serotonergic signaling. Although
there is solid evidence that SERT forms oligomeric complexes,
the exact stoichiometry of the complexes and the fractions of
different coexisting oligomeric states still remain enigmatic.
Here we used single molecule fluorescence microscopy to obtain
the oligomerization state of the SERT via brightness analysis of
single diffraction-limited fluorescent spots. Heterologously
expressed SERT was labeled either with the fluorescent inhibitor
JHC 1-64 or via fusion to monomeric GFP. We found a variety
of oligomerization states of membrane-associated transporters,
revealing molecular associations larger than dimers and
demonstrating the coexistence of different degrees of oligomerization
in a single cell; the data are in agreement with a linear
aggregation model. Furthermore, oligomerization was found to be
independent ofSERTsurface density, and oligomers remained stable
over several minutes in the live cell plasma membrane.
Together, the results indicate kinetic trapping of preformed SERT
oligomers at the plasma membrane.
Created from the Publication Database of the Vienna University of Technology.