Mislocalization of LBR in cells with mutation LMNA R377H. Fibroblasts (a,b,e) and myoblasts (c,d,f) from control (a,c) or patient (b,d,e,f) were double labelled with a mAb directed against lamin B2 (a-d) or lamin A/C (e,f) and with guinea pig antibodies recognizing LBR (a'-f') and then analyzed by confocal microscopy. Note the colocalization of lamin B and LBR at the nuclear envelope in control cells (a",c"). In contrast, in patient cells LBR shows also a cytoplasmic localization (b",d",e",f"). Merged pictures are shown in a"-f". The contour of the nucleus is marked by a white line (e"). Bar: 15 µm.