Browsing by Author "Martinac, B"

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    Bilayer-mediated clustering and functional interaction of MscL channels
    (Cell Press, 2011-03-02) Grage, SL; Keleshian, AM; Turdzeladze, T; Battle, AR; Tay, WC; May, RP; Holt, SA; Contera, SA; Haertlein, M; Moulin, M; Pal, P; Rohde, PR; Forsyth, VT; Watts, A; Huang, KC; Ulrich, AS; Martinac, B
    Mechanosensitive channels allow bacteria to respond to osmotic stress by opening a nanometer-sized pore in the cellular membrane. Although the underlying mechanism has been thoroughly studied on the basis of individual channels, the behavior of channel ensembles has yet to be elucidated. This work reveals that mechanosensitive channels of large conductance (MscL) exhibit a tendency to spatially cluster, and demonstrates the functional relevance of clustering. We evaluated the spatial distribution of channels in a lipid bilayer using patch-clamp electrophysiology, fluorescence and atomic force microscopy, and neutron scattering and reflection techniques, coupled with mathematical modeling of the mechanics of a membrane crowded with proteins. The results indicate that MscL forms clusters under a wide range of conditions. MscL is closely packed within each cluster but is still active and mechanosensitive. However, the channel activity is modulated by the presence of neighboring proteins, indicating membrane-mediated protein-protein interactions. Collectively, these results suggest that MscL self-assembly into channel clusters plays an osmoregulatory functional role in the membrane.© 2011, Cell Press
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    Microgravity × radiation: a space mechanobiology approach toward cardiovascular function and disease
    (Frontiers Media S.A., 2021-10-29) Basirun, C; Ferlazzo, ML; Howell, NR; Liu, GJ; Middleton, RJ; Martinac, B; Narayanan, SA; Poole, K; Gentile, C; Chou, J
    In recent years, there has been an increasing interest in space exploration, supported by the accelerated technological advancements in the field. This has led to a new potential environment that humans could be exposed to in the very near future, and therefore an increasing request to evaluate the impact this may have on our body, including health risks associated with this endeavor. A critical component in regulating the human pathophysiology is represented by the cardiovascular system, which may be heavily affected in these extreme environments of microgravity and radiation. This mini review aims to identify the impact of microgravity and radiation on the cardiovascular system. Being able to understand the effect that comes with deep space explorations, including that of microgravity and space radiation, may also allow us to get a deeper understanding of the heart and ultimately our own basic physiological processes. This information may unlock new factors to consider with space exploration whilst simultaneously increasing our knowledge of the cardiovascular system and potentially associated diseases. © 2021 Basirun, Ferlazzo, Howell, Liu, Middleton, Martinac, Narayanan, Poole, Gentile and Chou.