Fig. 2: Expression of Sun2 protein and F-actin polymerization are increased in MSCs cultured on stiffer surface, and Sun2 is more enriched in nuclear blebs.
From: Nuclear softening mediated by Sun2 suppression delays mechanical stress-induced cellular senescence
A Mesenchymal stromal/stem cells (MSCs) were isolated from gastrocnemius (GM) muscle tissues of 5-month-old WT and Z24−/− mice, and cultured on surface with different substrate stiffness (2% collagen-coated plastic, ~50 kPa; non-coated glass, ~50,000 kPa). Immunofluorescent staining of Sun2 (red) and staining of F-actin with Alex Fluo 488 phalloidin (green) showed increased Sun2 expression and F-actin polymerization in WT and Z24−/− MSCs cultured on glass. Arrows mark nucleus with nuclear blebs. B Statistics of the level of Sun2 in F-actin in different groups of cells. C Immunofluorescent staining of Sun1 and Sun2 in Z24−/− MSCs with nuclear blebs showed the enrichment of Sun2 in nuclear blebs; immunofluorescent staining of Nesprin2 and Sun2 in Z24−/− MSCs with nuclear blebs showed co-localization of Nesprin2 and Sun2 in nuclear blebs. Arrows mark nuclear blebs. N ≥ 6 for data analysis, with at least three biological replicates and two technical replicates. * indicates p < 0.05.
