Fig. 2. Real-time quantitative PCR analysis of myosin heavy chain (MHC)-related genes in space flown worms. Expression levels of MHCs (myo-1, -2, -3 and unc-54), paramyosin (unc-15), transcription factors (hlh-1, pha-4, peb-1, ceh-22) and actin (act-3) are shown. The mRNA levels of each gene were adjusted to that of GAPDH (gpd-2) mRNA, which was used as the internal standard. All MHC-related genes decreased in the space-flown worms. Actin levels remained unchanged in response to spaceflight. A summary of the PCR and DNA microarray values is shown in Table 2. Values in the column of real-time PCR are means ± s.e.m. (P<0.05). F, space-flown worms; G, ground controls.