Fig. 4 . Myonuclei positioning is not affected in Syne-2^-/- mice, but an MCK-driven Syne-2 KASH transgenic protein displays a dominant-negative effect. (A,B) Anchorage of synaptic nuclei in Syne-2^-/- mice (B) was similar to wild-type mice (A). Green, anti-SUN2 labeled myonuclei; red, BTX. (C,D) An MCK-promoter-driven C-terminal fragment of Syne-2 containing the KASH domain was localized to the nuclear envelope in skeletal muscle cells (D). Blue, DAPI; green, anti-myc. (E-F') Overexpressed Syne-2 KASH fragment expelled synaptic nuclei from under the NMJ to the peripheral region (F,F'), compared with wild-type (E,E'). Noticeably, myonuclei expressing the transgene (green) rarely stayed under synapses (F'). Scale bars: 25 µm in B for A,B; 25 µm in C for C,D; 25 µm in F for E-F'.