@article{HartelGloggerJonesetal.2016,
  author    = {Hartel, Andreas J.W. and Glogger, Marius and Jones, Nicola G. and Abuillan, Wasim and Batram, Christopher and Hermann, Anne and Fenz, Susanne F. and Tanaka, Motomu and Engstler, Markus},
  title     = {N-glycosylation enables high lateral mobility of GPI-anchored proteins at a molecular crowding threshold},
  series = {Nature Communications},
  volume    = {7},
  journal   = {Nature Communications},
  doi       = {10.1038/ncomms12870},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-171368},
  year      = {2016},
  abstract  = {The protein density in biological membranes can be extraordinarily high, but the impact of molecular crowding on the diffusion of membrane proteins has not been studied systematically in a natural system. The diversity of the membrane proteome of most cells may preclude systematic studies. African trypanosomes, however, feature a uniform surface coat that is dominated by a single type of variant surface glycoprotein (VSG). Here we study the density-dependence of the diffusion of different glycosylphosphatidylinositol-anchored VSG-types on living cells and in artificial membranes. Our results suggest that a specific molecular crowding threshold (MCT) limits diffusion and hence affects protein function. Obstacles in the form of heterologous proteins compromise the diffusion coefficient and the MCT. The trypanosome VSG-coat operates very close to its MCT. Importantly, our experiments show that N-linked glycans act as molecular insulators that reduce retarding intermolecular interactions allowing membrane proteins to function correctly even when densely packed.},
  language  = {en}
}
@article{MeiserMohammadiVogeletal.2023,
  author    = {Meiser, Elisabeth and Mohammadi, Reza and Vogel, Nicolas and Holcman, David and Fenz, Susanne F.},
  title     = {Experiments in micro-patterned model membranes support the narrow escape theory},
  series = {Communications Physics},
  volume    = {6},
  journal   = {Communications Physics},
  doi       = {10.1038/s42005-023-01443-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-358121},
  year      = {2023},
  abstract  = {The narrow escape theory (NET) predicts the escape time distribution of Brownian particles confined to a domain with reflecting borders except for one small window. Applications include molecular activation events in cell biology and biophysics. Specifically, the mean first passage time τ can be analytically calculated from the size of the domain, the escape window, and the diffusion coefficient of the particles. In this study, we systematically tested the NET in a disc by variation of the escape opening. Our model system consisted of micro-patterned lipid bilayers. For the measurement of τ, we imaged diffusing fluorescently-labeled lipids using single-molecule fluorescence microscopy. We overcame the lifetime limitation of fluorescent probes by re-scaling the measured time with the fraction of escaped particles. Experiments were complemented by matching stochastic numerical simulations. To conclude, we confirmed the NET prediction in vitro and in silico for the disc geometry in the limit of small escape openings, and we provide a straightforward solution to determine τ from incomplete experimental traces.},
  language  = {en}
}