Fig. 6. Overexpression of lamin mutants causes a loss of nuclear envelope-associated emerin. Transfected HeLa cells (arrowheads) were doubled labeled with rabbit anti-emerin and monoclonal anti-HA antibodies. As shown in (A), expression of both LaA L530P and LaC L530P is associated with a decline in the levels of emerin detected in the nuclear envelope. Rather than distributing throughout the peripheral ER, mislocalized emerin was almost invariably found in cytoplasmic foci (arrows). As indicated in (B), comparison of cells expressing wild-type versus L530P mutants reveal that this effect is statistically significant (P<0.001). Similar, albeit milder effects are observed with LaA L85R and LaA/C N195K. LaC L85R and LaA/C R482W caused no significant (NS) emerin loss when compared with their wild-type counterparts.