“…Embryonic endoderm gives rise to the bladder urothelium while the connective tissues and smooth muscle of the developing bladder are derived from the peri-cloacal mesenchyme (Haraguchi et al, 2007;Brenner-Anantharam et al, 2007). Genetic studies indicate the homeobox genes play an important role in determining the global patterning of the urogenital system (Satokata et al, 1995;Sciavolino et al, 1997;Warot et al, 1997;Goodman and Scambler, 2001;de Santa and Roberts, 2002;Troy et al, 2003), while key signaling molecules like sonic hedgehog and wnts have been implicated in determining the regional patterning within specific urogenital organs (Perriton et al, 2002;Freestone et al, 2003;Mericskay et al, 2004). The differentiation program responsible for the development of smooth muscle involves the complex interaction of epigenetic and genetic events including chromatin remodeling and acetylation, the SRF-myocar-din pathway, basic helix-loop-helix factors, AP-1 complex genes, and the ternary complex factors of the ETS domain family (Manabe and Owens, 2001;Chen et al, 2002;Du et al, 2003;Kumar and Owens, 2003;Miano, 2003;Wang et al, 2003Wang et al, , 2004Yoshida et al, 2003;Buchwalter et al, 2004;Spin et al, 2004;McDonald et al, 2006;Pipes et al, 2006).…”