Indirect immunofluorescence in conjunction with Northern and Western blot analysis were used to identify the presence of skelemin, a myosin-associated protein, in smooth muscle. Feline uterus was cryosectioned and triple-stained for skelemin, smooth muscle myosin, and desmin. I observed that skelemin antibodies colocalized with the myosin-II filaments as well as the desmin intermediate filament cytoskeleton. This is the first evidence of a myosin-associated protein within smooth muscle, and it raises the possibility that smooth muscle myosin may be more organized than has been assumed. Antisense oligonucleotide treatment was used to analyze the underexpression of skelemin protein in developing embryoid bodies. Skelemin underexpression was seen to cause loss of cell-cell as well as cell-substrate adhesion. Time lapse video microscopy was used to analyze the role of the cell cycle in cell type choice during mammalian development. Discussed are methods employed to improve resolution for accurate analysis.