Fig. 4

Lamin A/C and/or emerin mediate nuclear shape changes in embryonic stem cell differentiation. ES cells of wild type (wt), lmna (−/−), emd (−/−), and lmna (−/−);emd (−/−) ES cells were treated with 1 μM RA for 4 days. Immunostainings for Gata4 and Oct3/4 to indicate differentiated or undifferentiated cells, and lamin B to mark nuclear outline, were imaged by confocal microscopy, followed by analysis using Volocity 3D imaging software. The measurements obtained (Table 2) were used to analyze nuclear shape. a The nuclear dimensions are plotted as mean ± s.d. Only the wild type ES cells show statistically significant (*P < 0.0005) changes in nuclear shape between differentiated and undifferentiated states. b The changes in nuclear shape were modeled for illustrative purposes. Shape factors (c), nuclear volume (d), and nuclear surface area (e) were calculated based upon the quantified dimensions