부산대학교 도서관

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.cell.2009.07.051 Byline: Ceren Korkut (1), Bulent Ataman (1), Preethi Ramachandran (1), James Ashley (1), Romina Barria (1), Norberto Gherbesi (1), Vivian Budnik (1) Keywords: SIGNALING; CELLBIO; MOLNEURO Abstract: Wnts play pivotal roles during development and in the mature nervous system. However, the mechanism by which Wnts traffic between cells has remained elusive. Here we demonstrate a mechanism of Wnt transmission through release of exosome-like vesicles containing the Wnt-binding protein Evenness Interrupted/Wntless/Sprinter (Evi/Wls/Srt). We show that at the Drosophila larval neuromuscular junction (NMJ), presynaptic vesicular release of Evi is required for the secretion of the Wnt, Wingless (Wg). We also show that Evi acts cell-autonomously in the postsynaptic Wnt-receiving cell to target dGRIP, a Wg-receptor-interacting protein, to postsynaptic sites. Upon Evi loss of function, dGRIP is not properly targeted to synaptic sites, interfering with postsynaptic Wnt signal transduction. These findings uncover a previously unknown cellular mechanism by which a secreted Wnt is transported across synapses by Evi-containing vesicles and reveal trafficking functions of Evi in both the Wnt-producing and the Wnt-receiving cells. For a video summary of this article, see the PaperFlick file with the available online. Author Affiliation: (1) Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01655, USA Article History: Received 9 March 2009; Revised 3 June 2009; Accepted 31 July 2009 Article Note: (miscellaneous) Published: October 15, 2009