Significance of Knotted Structures for Function of Proteins and Nucleic Acids - September 17-21, 2014

Significance of Knotted Structures for Function of Proteins and Nucleic Acids

Poster Session II

35 – POS Board 7 Balls and Sticks in Medically Important Proteins under Mechanical Stress Wieslaw Nowak , Lukasz Peplowski, Rafal Jakubowski, Karolina Mikulska-Ruminska, Jakub Rydzewski. Institute of Physics, Torun, Poland. The human brain contains over 10**14 synapses between neurons. Hundreds of different protein pairs govern proper development and functioning of neuronal networks. Do they contain protein knots? Mechanical stability of cytoskeleton to large extent depends on spectrin repeats. Individual helices are tightly coupled to create microfibers. The lack of nanomechnical stability in both cellular environments may lead to serious disorders and health hazards. The data on important synaptic components, such as neurexins (NRXNs – related to autism), neuroligins (NLGNs -linking pre- and post-synaptic part of the synaptic cleft), contactins (CNTNs present in Ranvier nodes), reelins (RELNs - regulation of neuronal migration) and keratins (parts of epidermis) stemming from single molecule Virtual Atomic Force Microscopy computational experiments will be presented. In this presentation we will show how our efforts in understanding of nanomechanics of these systems led to developing steered molecular dynamics simulation protocols that may help to interpret real AFM spectra and to see performance of such modular proteins subject to extreme mechanical stress. Both all-atoms and coarse-grained simulations contribute to better mechanical models of these intriguing systems. Supported by NCN (UMO-2012/05/N/ST3/03178), NCU grant 1142-F, NCN grants No. N202 262038 and No. N519 578138. KM acknowledges SCIEX fellowship.

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