by Keyword: membrane curvature

Schamberger, B, Ziege, R, Anselme, K, Ben Amar, M, Bykowski, M, Castro, APG, Cipitria, A, Coles, RA, Dimova, R, Eder, M, Ehrig, S, Escudero, LM, Evans, ME, Fernandes, PR, Fratzl, P, Geris, L, Gierlinger, N, Hannezo, E, Iglic, A, Kirkensgaard, JJK, Kollmannsberger, P, Kowalewska, L, Kurniawan, NA, Papantoniou, I, Pieuchot, L, Pires, THV, Renner, LD, Sageman-Furnas, AO, Schroder-Turk, GE, Sengupta, A, Sharma, VR, Tagua, A, Tomba, C, Trepat, X, Waters, SL, Yeo, EF, Roschger, A, Bidan, CM, Dunlop, JWC, (2023). Curvature in Biological Systems: Its Quantification, Emergence, and Implications across the Scales Advanced Materials 35, 2206110

Surface curvature both emerges from, and influences the behavior of, living objects at length scales ranging from cell membranes to single cells to tissues and organs. The relevance of surface curvature in biology is supported by numerous experimental and theoretical investigations in recent years. In this review, first, a brief introduction to the key ideas of surface curvature in the context of biological systems is given and the challenges that arise when measuring surface curvature are discussed. Giving an overview of the emergence of curvature in biological systems, its significance at different length scales becomes apparent. On the other hand, summarizing current findings also shows that both single cells and entire cell sheets, tissues or organisms respond to curvature by modulating their shape and their migration behavior. Finally, the interplay between the distribution of morphogens or micro-organisms and the emergence of curvature across length scales is addressed with examples demonstrating these key mechanistic principles of morphogenesis. Overall, this review highlights that curved interfaces are not merely a passive by-product of the chemical, biological, and mechanical processes but that curvature acts also as a signal that co-determines these processes.© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.

JTD Keywords: biological systems, butterfly wing scales, cubic membranes, extracellular-matrix, geometry, mechanotransduction, membrane curvature, morphogenesis, neotissue growth, pattern-formation, soft materials, surface curvature, tissue-growth, Biological systems, Collective cell-migration, Surface curvature

Raote, Ishier, Chabanon, Morgan, Walani, Nikhil, Arroyo, Marino, Garcia-Parajo, Maria F., Malhotra, Vivek, Campelo, Felix, (2020). A physical mechanism of TANGO1-mediated bulky cargo export eLife 9, e59426

The endoplasmic reticulum (ER)-resident protein TANGO1 assembles into a ring around ER exit sites (ERES), and links procollagens in the ER lumen to COPII machinery, tethers, and ER-Golgi intermediate compartment (ERGIC) in the cytoplasm (Raote et al., 2018). Here, we present a theoretical approach to investigate the physical mechanisms of TANGO1 ring assembly and how COPII polymerization, membrane tension, and force facilitate the formation of a transport intermediate for procollagen export. Our results indicate that a TANGO1 ring, by acting as a linactant, stabilizes the open neck of a nascent COPII bud. Elongation of such a bud into a transport intermediate commensurate with bulky procollagens is then facilitated by two complementary mechanisms: (i) by relieving membrane tension, possibly by TANGO1-mediated fusion of retrograde ERGIC membranes and (ii) by force application. Altogether, our theoretical approach identifies key biophysical events in TANGO1-driven procollagen export.

JTD Keywords: Membrane tension, Procollagen export, Secretory pathway, Membrane curvature, Membrane dynamics, Budding