Fig. 4. Steady-state myosin A, myosin B and actin mRNA levels in N2 and CB1214. Total RNA was prepared and hybridized with gene-specific riboprobes (A), and steady-state mRNA levels were determined by normalization to total actin mRNA (B). The results demonstrate that in CB1214, the steady-state level of myosin B mRNA is approximately 60% that in the wild-type N2. The blot for the myosin A probe has a significantly longer exposure time due to the lower amount of myosin A in the muscle (Honda and Epstein, 1990). Mean values are based on four independent determinations.