The Wild Icotinib Conspriracy

Sef and spry4 are known to be transcriptionally activated by FGF application and participate in a negative feedback loop to attenuate FGF signaling ( Furthauer et al., 2002?and?Furthauer et al., 2001). Overexpression of the nodal-related genes cyclops and squint leads to the induction of floating head (flh) in developing zebrafish embryos ( Gritsman et al., 2000). Nodal signaling directly induces xbp1 transcription ( Bennett et al., 2007). The expression of ved and vent was negatively regulated by the direct target boz of maternal Wnt signaling and dependent on BMP signaling at the mid-to-late gastrula stage ( Kawahara et al., 2000, Melby et al., 2000?and?Ramel et al., 2005). Injection of ��-catenin RNA activates expression of squint ( Kelly et YES1 Thiazovivin al., 2000). dkk1 is a target gene of the pre-MBT Wnt signaling and is able to inhibit the post-MBT Wnt signaling in the putative head patterning tissue ( Shinya et al., 2000). Bozozok (boz) is a direct target of the maternal ��-catenin signal ( Leung et al., 2003?and?Ryu et al., 2001). Expression of the anterior neuroectodermal marker otx2 was enhanced by overexpression of a constitutive active ��-catenin ( Xiong et al., 2006). Wnt8a activates the zygotic Wnt signaling ( Erter et al., 2001) and tbx6 is activated by both Wnt and Bmp signaling ( Szeto and Kimelman, 2004). We found that expression of sef, spry4, xbp1, flh, ved and vent was minimally, if at all, affected by ectopic expression and knockdown of cav-1�� or -1�� in early developing embryos ( Fig.?4A). However, expression of squint, dkk1, boz and otx2 was significantly inhibited in >?60% of embryos injected with 300?pg of capped mRNA for cav-1�� or -1�� ( Figs.?4A and B), and enhanced in >?75% of embryos injected with 10?ng of cav-1��-MO or -1��-MO ( Figs.?4A and C). In addition, expression of two genes wnt8a and tbx6 that are associated with activity of zygotic Wnt signaling were not significantly affected by Cav-1 overexpression Icotinib or knockdown ( Fig.?4A). These findings indicate that Nodal, FGF, and BMP signaling pathways may not be appreciably regulated by Cav-1 proteins during early development of zebrafish and that the ventralizing activity of Cav-1 appears to be mainly associated with maternal Wnt signaling. To further substantiate these observations, Top-flash, Bre and (CAGA)12-Luc reporters were used to detect effects of Cav-1 proteins on activation of Wnt, BMP and Nodal/TGF-�� signaling pathways, respectively. Capped mRNA of cav-1�� or -1�� was co-injected with one of these reporters into one-cell stage embryos. Luciferase assays were performed with embryonic lysates at 6, 12 or 24?hpf. Injection of 300?pg capped cav-1�� mRNA or -1�� mRNA significantly inhibited activity of Top-flash reporter at 6?hpf ( Fig.?4D; p?