title: Closed membrane shapes with attached BAR domains subject to external force of actin filaments.
abstract: Membrane deformations induced by attached BAR superfamily domains could trigger or facilitate the growth of plasma membrane protrusions. The BAR domain family consists of BAR, F-BAR and I-BAR domains, each enforcing a different local curvature when attached to the membrane surface. Our theoretical study mainly focuses on the role of I-BAR in the membrane tubular deformations generated or stabilised by actin filaments. The influence of the area density of membrane attached BAR domains and their intrinsic curvature on the closed membrane shapes (vesicles) was investigated numerically. We derived an analytical approximative expression for the critical relative area density of BARs at which the membrane tubular protrusions on vesicles are most prominent. We have shown that the BARs with a higher intrinsic curvature induce thinner and longer cylindrical protrusions. The average orientation of the membrane attached BARs is altered when the vesicle shape is subjected to external force of growing actin rod-like structure inside a vesicle. The average orientation angle of membrane attached BARs may indicate whether the actin filaments are just stabilising the protrusion or generating it by stretching the vesicle.
authors: Laboratory of Biophysics, Faculty of Electrical Engineering, University of Ljubljana, Tržaška 25, SI-1000 Ljubljana, Slovenia. Electronic address: mesarec.luka@gmail.com.
authors: Luka
authors: L
authors: Mesarec
authors: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
authors: Wojciech
authors: W
authors: Góźdź
authors: Laboratory of Biophysics, Faculty of Electrical Engineering, University of Ljubljana, Tržaška 25, SI-1000 Ljubljana, Slovenia; Laboratory of Clinical Biophysics, Faculty of Health Sciences, University of Ljubljana, Zdravstvena 5, SI-1000 Ljubljana, Slovenia.
authors: Veronika Kralj
authors: VK
authors: Iglič
authors: Department of Physics, Faculty of Natural Sciences and Mathematics, University of Maribor, Koroška cesta 160, SI-2000 Maribor, Slovenia; Jožef Stefan Institute, P.O. Box 3000, SI-1000 Ljubljana, Slovenia.
authors: Samo
authors: S
authors: Kralj
authors: Laboratory of Biophysics, Faculty of Electrical Engineering, University of Ljubljana, Tržaška 25, SI-1000 Ljubljana, Slovenia; Laboratory of Clinical Biophysics, Faculty of Health Sciences, University of Ljubljana, Zdravstvena 5, SI-1000 Ljubljana, Slovenia.
authors: Aleš
authors: A
authors: Iglič
mesh_terms: D008841:Actin Cytoskeleton / Q000737:chemistry* / Q000378:metabolism; D000465:Algorithms; D002462:Cell Membrane / Q000737:chemistry* / Q000378:metabolism; D050556:Fatty Acid-Binding Proteins; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D000072417:Protein Domains; D013314:Stress, Mechanical
chemical_list: C119539:BAIAP2 protein, human; C497031:FCHO2 protein, human; D050556:Fatty Acid-Binding Proteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; C075637:amphiphysin
keywords: Actin filaments; BAR domains; Biological membranes; Membrane curvature; Membrane proteins; Membrane tubular deformations; Numerical study; Vesicles