Description |
Dorsal closure in Drosophila is an embryogenic event that involves coordinated cellular shape changes. A series of interconnected signaling cascades are utilized to accomplish this task, one of which is the Decapentaplegic (Dpp) pathway. Dpp is a member of the TFG-β family of secreted cytokines, which are responsible for regulating a wide range of cellular activities. During dorsal closure, Dpp binds to a heteromeric kinase receptor complex to transduce a signal downstream and regulate cellular activity. Previous research on the gene mummy has implicated the involvement of GlcNAC, a glucose derivative, in affecting proper downstream Dpp signaling. An RNAi screen targeting glycosyltransferases revealed that Super Sex Combs (Sxc), the Drosophila OGlcNAc Transferase (OGT), could be involved in modulating the Dpp pathway. Here, it is demonstrated that Sxc is a Dpp signal antagonist, and functions specifically on the Type I BMP receptor Saxophone (Sax) through an O-linked GlcNAc attachment to restrict its activity. Current research suggests that in this manner, Sxc may function as a glucose-sensitive nutrient sensor for cells. |