...Tal Rousso; Jeremy Lynch; Shaul Yogev; Siegfried Roth; Eyal D. Schejter; Ben-Zion Shilo Egfr ligand processing in Drosophila involves trafficking of the ligand precursor by the chaperone Star from the endoplasmic reticulum (ER) to a secretory compartment, where the precursor is cleaved...

..., and an element that inhibits repressor activity to promote translation in the embryo. Furthermore, we show that the STAR/KH domain protein GLD-1 binds directly and specifically to the repressor element. Depletion of GLD-1 activity by RNA interference causes loss of endogenous glp-1 mRNA repression in early...

... to the Egfr; however, only the soluble form can trigger Egfr signaling, which is consistent with the observed cleavage of Grk in vivo. We find that the two transmembrane proteins Star and Brho potentiate the activity of mbGrk. These two proteins collaborate to promote an activating proteolytic cleavage...

..., Egfr encodes the Drosophila EGF-Receptor, spitz ( spi ) and vein ( vn ) encode EGF-related ligands, and rhomboid ( rho ) and Star ( S ) encode membrane proteins. In this study, we show that rho -mediated hyperactivation of the EGFR/MAPK pathway is required for vein formation throughout late larval...

... ectoderm. This work shows that the midline provides the site for Spitz expression and processing. The Rhomboid and Star proteins are also expressed and required in the midline. The ectodermal defects of spitz, rho or Star mutant embryos could be rescued by inducing the expression of the respective normal...