Loss of HSPB7 results in FLNC protein upregulation and aggregation.

Confocal micrographs of longitudinal sections (A) and cross-sections (B) of the heart. FLNC aggregation (arrowheads) was observed only in the mutant cardiomyocytes. Extracellular matrix accumulation was labeled using wheat germ agglutinin (WGA). The nucleus was visualized through Hoechst 33342 staining. Scale bar: 50 μm. (C) Immunoblot analysis and quantitation (D) of the expression levels of FLNC in the cardiac muscle. The muscle homogenate supernatant (S) and pellet (P) fractions were analyzed from control and CKO mice at d7 after tamoxifen administration. GAPDH and Coomassie Blue staining were used to verify the loading amount in the supernatant and pellet. n = 3 per group. Data are presented as means ± SD. *, P < 0.05 relative to the control.