Nanomechanical properties of composite protein networks of erythroid membranes at lipid surfaces

作者：Encinar Mario; Casado Santiago; Calzado Martin Alicia; Natale P; Paulo Alvaro San; Calleja Montserrat; Velez Marisela; Monroy Francisco; Lopez Montero Ivan

来源：Colloids and Surfaces B: Biointerfaces , 2017, 149: 174-183.

DOI：10.1016/j.colsurfb.2016.10.022

• Giant vesicles
• Erythrocyte
• Lipid membrane
• Cytoskeleton reconstitution
• AFM
• PeakForce tapping quantitative nanomechanical mapping

Erythrocyte membranes have been particularly useful as a model for studies of membrane structure and mechanics. Native erythroid membranes can be electroformed as giant unilamellar vesicles (eGUVs). In the presence of ATP, the erythroid membrane proteins of eGUVs rearrange into protein networks at the microscale. Here, we present a detailed nanomechanical study of individual protein microfilaments forming the protein networks of eGUVs when spread on supporting surfaces. Using Peak Force tapping Atomic Force Microscopy (PF-AFM) in liquid environment we have obtained the mechanical maps of the composite lipid-protein networks supported on solid surface. In the absence of ATP, the protein pool was characterized by a Young's Modulus E-pool approximate to 5-15 MPa whereas the complex filaments were found softer after protein supramolecular rearrangement; E-fil approximate to 0.4 MPa. The observed protein softening and reassembling could be relevant for understanding the mechanisms of cytoskeleton reorganization found in pathological erythrocytes or erythrocytes that are affected by biological agents.

• 出版日期2017-1-1