Fig. 3. Absence of sex muscles in soc-2; ayIs15 [egl-15(neu^*)] animals. Muscle cells are visualized with rhodamine-phalloidin and muscle nuclei with a P_myo-3::GFP reporter. Broad bands of body wall muscles can be seen just below the focal plane. Sex muscles are labeled in A. The control strains, ccIs4251 [P_myo-3::GFP] (A) and ccIs4251; soc-2(n1774) (B), have wild-type sex muscles and body wall muscles. (C) soc-2(n1774); ayIs15 [egl-15(neu^*); P_myo-3::GFP]. SM descendants in these animals do not stain with rhodamine-phalloidin and fail to express P_myo-3::GFP. The rhodamine-phalloidin staining and the pattern of P_myo-3::GFP expression remains unchanged in the surrounding body wall musculature. (D) soc-2(n1774) ayIs18 [egl-15(5B^*)]; (E) soc-2(n1774); ayIs27 [egl-15(5A^*)]. All animals are positioned in a ventrolateral view with the head oriented towards the left. A broken line in A represents the position of the vulva. um1, uterine muscles 1; vm1, vulval muscles 1; vm2, vulval muscles 2. The um2s are very broad and contain loosely organized actin filaments. Using ccIs4656 [P_16Nde::GFP], which can also be used to visualize both vms and ums in the absence of ayIs15, there are no observable sex muscles in an ayIs15 background. The vulval musculature was scored because of the poor reproducibility of um visualization by either technique. Scale bar: 10 µm.