A sweet spot in the FGFR signal transduction pathway

Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
Science Signaling (Impact Factor: 6.28). 01/2012; 5(207):pe1. DOI: 10.1126/scisignal.2002789
Source: PubMed


The hexosamine biosynthetic pathway, whose end product is UDP-N acetylglucosamine (UDP-GlcNAc), lies at the base of cellular glycosylation pathways, including glycosylation of lipids, formation of heparin sulfated proteoglycans, and N- and O-linked glycosylation of proteins. Forward genetic studies in Drosophila have revealed that mutations in genes encoding different enzymes of the hexosamine biosynthetic pathway result in reduction of UDP-GlcNAc to different extents, with a consequent disruption of distinct glycosylation pathways and developmental processes. A maternal and zygotic loss-of-function screen has identified mutations in nesthocker (nst), which encodes an enzyme in the hexosamine biosynthetic pathway. Embryos lacking maternal and zygotic nst gene products show defective O-GlcNAcylation of a fibroblast growth factor receptor (FGFR)-specific adaptor protein, which impairs FGFR-dependent migration of mesodermal and tracheal cells.

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Available from: Amin S Ghabrial, Jul 07, 2014
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