Expression Patterns of Smad Family Members during Embryogenesis of the Ascidian Halocynthia roretzi

The involvement of three signal transduction pathways in botryllid ascidian astogeny, as revealed by expression patterns of representative genes

“…In solitary ascidian species, STP expression and functions during ontogenic stages have been elucidated for Wnt/b-catenin (Niwano et al, 2009;Hudson et al, 2013), TGF-b (Kobayashi et al, 1999;Kobayashi and Makabe, 2001;Hino et al, 2003;Kawashima et al, 2005;Christiaen et al, 2010;Nishide et al, 2012) and MAPK/ ERK (Bertrand et al, 2003;Hudson et al, 2003;Nishida, 2003;Pasini et al, 2006;Chambon et al, 2007;Sakabe et al, 2006) pathways alone, or in combination with other STPs (Hudson et al, 2007;Lemaire, 2009;Pasini et al, 2012;Sasakura et al, 2012;Squarzoni et al, 2011). This has not been extensively studied in colonial species where astogenic and ontogenic pathways are developing side by side and in concert.…”