Fig. 7

Full-length SSPN is expressed only in the surface membrane and loss of SSPN does not affect nSPN localization. a–c Simultaneous TPLSM images of immunolocalization of SSPN, μSPN, nSPN (a) and SHG (b) obtained from an FDB muscle isolated from wild-type mice and labeled with affinity-purified Rabbit 3 (R3) polyclonal antibodies that recognize an N-terminal region that is common to all three SSPN isoforms (Alexa 488). c The superposition of the images on a and b. d–f Simultaneous TPLSM images of immunolocalization of nSPN (d) and SHG (e) obtained from an FDB muscle isolated from SSPN-null mice and labeled with Rabbit 3 (R3) polyclonal antibodies (Alexa 488). Note that exon 2 and part of exon 3 were targeted for deletion in the SSPN nulls [28], which disrupts SSPN and μSPN, but not nSPN, expression. f The superposition of the images on d and e. g A magnified view of the area enclosed by the white rectangle in c. h A magnified view of the area enclosed by the white rectangle in f. White arrows in g and h point to the presence (g) or absence (h) of sarcolemmal labeling in the wild-type and SSPN-null mice, respectively. Sarcomere length ~3 μm. Scale bar, 10 μm