Non-erythrocyte spectrin network preferentially stabilizes flat membrane and enhances cell stiffness.

ABSTRACT: Spectrin αII and βII, the predominant non-erythroid isoforms, assemble into cytoskeletal networks that shape the plasma membrane. However, how these networks interact with membranes of different curvatures remains unclear. Using microfluidic deformation cytometry, we show that spectrin βII overexpression increases the apparent stiffness of MDA-MB-231 breast cancer cells. Fluorescence microscopy further demonstrates that spectrin is excluded from highly curved regions and enriched on flatter membranes in vivo, specifically those with an absolute curvature |κ| < 0.2 µm^-1. Consistently, in vitro reconstitution with spherical supported lipid bilayers (SSLBs) shows that purified spectrin heterodimers preferentially bind low-curvature membranes, exhibiting ∼15-fol

SUBMITTER: Komikawa T 

PROVIDER: S-EPMC12699370 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature