Fig. 2

Physiological adaptations to microgravity are muscle type-specific. A Representative immunofluorescence images of the gastrocnemius and quadriceps stained for laminin and MyHC isoforms (left panel laminin, green; MyHC I, red) (right panel MyHC II, green) in ground control and flight mice. B Box-and-whisker plots quantify the myofiber CSA distribution (mean value, upper/lower quartiles, and maximum/minimum) in both gastrocnemius and quadriceps. Asterisks represent significance by two-tailed t-test (**p < 0.01). C Box-and-whisker plots quantify the muscle fiber type distribution (mean value, upper/lower quartiles, and maximum/minimum) in both gastrocnemius and quadriceps. Asterisks represent significance by two-tailed t-test (**p < 0.01). D Some fibers (yellow arrows) within the gastrocnemius of spaceflown mice were co-stained by both MyHC isoforms