The brain is the source of thoughts, perceptions, emotions, memories and actions. Neural signaling, the foundation of brain activity, must be precisely regulated to prevent neuronal disorders that may cause Parkinson's disease, schizophrenia, compulsive behaviors and addiction. Such a precise regulation is achieved by key signaling proteins, voltage-gated sodium and potassium channels for electrical signaling and calcium - bound synaptotagmin for chemical signaling. Here, innovations in computer simulation techniques will be used to investigate the molecular mechanism of neural firing induced by voltage-gated sodium and potassium channels and membrane fusion triggered by synaptotagmin.
The cells of higher life forms, so-called eukaryotic cells, are subdivided through many internal membranes made of lipid bilayers. The internal membranes assume numerous shapes, like spheres, tubes or parallel sheets. Outside of cells, biological membranes adopt usually flat shapes and the question arises, how do eukaryotic cells sculpt their inner membranes? The question of flat membrane sculpting is particularly interesting also as mature cells constantly produce new membrane shapes, for example spherical vesicles filled with certain biomolecules destined for release into the extracellular space, a process called exocytosis. The cell has many mechanisms available for sculpting its membranes, one of them relying on proteins called BAR domains that act from the surface of lipid bilayers. Molecular modeling with NAMD and VMD has provided valuable views of BAR domains at work in case of the so-called N-BAR family (see the earlier highlights Protein Teamwork, Jun 2009 and Proteins Sculpting Cell Interior, Sep 2008). Researchers report now an extension of the earlier studies to the F-BAR domain family of membrane sculpting proteins. The new modeling work is particularly exciting as it can be directly compared to electron microscopy images of membrane tubes sculpted from flat membranes in experiments done outside of cells. The new studies reveal how F-BAR domains sculpt tubular membranes through the shape of dimerized domains and through F-BAR domains not acting individually, but as an army of F-BAR domains adopting an ordered formation on one side of the membrane. More on our F-BAR domain web page.
Structural mechanism of voltage-dependent gating in an isolated voltage-sensing domain.
Qufei Li, Sherry Wanderling, Marcin Paduch, David Medovoy, Abhishek Singharoy, Ryan McGreevy, Carlos Villalba-Galea, Raymond E. Hulse, Benoit Roux, Klaus Schulten, Anthony Kossiakoff, and Eduardo Perozo. Nature Structural & Molecular Biology, 21:244-252, 2014.
Biological visuo-motor control of a pneumatic robot arm.
Michael Zeller, K. R. Wallace, and Klaus Schulten. In Dagli et al., editors, Intelligent Engineering Systems Through Artificial Neural Networks, volume 5, pp. 645-650, New York, 1995. American Society of Mechanical Engineers.
A comparison of models of visual cortical map formation.
Edgar Erwin, Klaus Obermayer, and Klaus Schulten. In Frank H. Eeckman and James M. Bower, editors, Computation and Neural Systems, chapter 60, pp. 395-402. Kluwer Academic Publishers, 1993.
A "neural gas" network learns topologies.
Thomas Martinetz and Klaus Schulten. In Teuvo Kohonen, Kai Mäkisara, Olli Simula, and Jari Kangas, editors, Artificial Neural Networks, pp. 397-402. Elsevier, Amsterdam, 1991.
Dynamics of synchronous neural activity in the visual cortex.
Christian Kurrer, Benno Nieswand, and Klaus Schulten. In Teuvo Kohonen, Kai Mäkisara, Olli Simula, and Jari Kangas, editors, Artificial Neural Networks, pp. 133-138. Elsevier, Amsterdam, 1991.
