Loss of mDia2 compromises erythrocyte membrane skeleton structure. (A) TEM study of the membrane skeleton of ghost erythrocytes from the indicated mice. Data are representative of 13 randomly selected fields. (B) The length distributions of the spectrin tetramers with corresponding frequencies in ghost erythrocytes calculated based on the TEM images in panel A. (C) Computationally predicted stress of the membrane skeleton under uniaxial tension with the increased deformation (λ₁) of the indicated mice. A shear modulus $μ0=13.1pN/μm$ is estimated for mDia2^fl/fl cells and $μ0=26.5pN/μm$ for mDia2^fl/flVav-Cre cells. (D) STORM imaging analyses of actin protofilaments in ghost erythrocytes from the indicated mice. Bars represent 1 μm. (E) Western blot analyses of the indicated erythroid membrane skeleton proteins of ghost erythrocytes from the indicated mice. An equal number of cells was used. (F) Immunoprecipitation assay using IgG or mDia2 antibodies in normal human ghost erythrocytes. Western blot analyses were performed to determine the coprecipitated proteins. (G) Immunogold stain of mDia2 and electron microscopy analysis of normal human ghost erythrocytes. Yellow dots and blue stripes in the schematic spectrin graph indicate gold particles and spectrin bands, respectively.