Fig. 7. Traversal of premyofibrils and myofibrils through the nuclear grooves and invaginations. Confocal optical sections (XY planes) and three-dimensional reconstitutions of the orthogonal planes derived from these sections (XZ and YZ planes). (A-C) Rhodamine-phalloidin (red) and anti-sarcomeric MyHC (green) staining of myofibrils passing through the nuclear grooves (A) and the nuclear invaginations (B,C). Arrows point to the traversing myofibrils. (D) Rhodamine-phalloidin (red) and anti-nucleoporin p62 (green) staining of myofibrillar structures and nuclear pore complexes, respectively. Boxed area in YZ plane is magnified three times. (E) Rhodamine-phalloidin (red) and DiOC₆(3) (green) staining of myofibrillar structures and the ER together with the nuclear envelope, respectively. Bar, 10 µm.