title: The role of Bro1- domain-containing protein Myopic in endosomal trafficking of Wnt/Wingless.
abstract: Wingless (Wg) proteins are secreted-lipid-modified glycoproteins involved in tissue patterning and cell-fate specification. Wg secretion is regulated by a specialized mechanism involving a repertoire of proteins including Wntless (Wls). Here, we show that the Bro1-domain-containing protein Myopic (Mop) is indispensable for endosomal trafficking of Wg and Wls. Reductions in Mop leads to trapping of Wg and Wls in the early endosomes. Overexpression of the endosomal sorting protein Hepatocyte growth factor-regulated tyrosine kinase substrate (Hrs) rescues the trafficking defect caused by the mop loss of function. The vertebrate homolog of Mop, Histidine domain-containing protein tyrosine phosphatase (HDPTP), was also found to have a conserved role in Wnt trafficking. Our study highlights the importance of early endosomal trafficking for Wg secretion, and identifies a novel role for Mop in Wg signaling.
authors.affiliation: Simon Fraser University, Burnaby, Canada BC V5A1S6.
authors.forename: Tirthadipa
authors.initials: T
authors.lastname: Pradhan-Sundd
authors.affiliation: Simon Fraser University, Burnaby, Canada BC V5A1S6. Electronic address: everheye@sfu.ca.
authors.forename: Esther M
authors.initials: EM
authors.lastname: Verheyen
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism*; D004705:Endocytosis / Q000235:genetics*; D011992:Endosomes / Q000378:metabolism; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics; D017434:Protein Structure, Tertiary; D021381:Protein Transport / Q000235:genetics; D017027:Protein Tyrosine Phosphatases / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D034741:RNA, Small Interfering; D051153:Wnt Proteins / Q000378:metabolism; D060449:Wnt Signaling Pathway / Q000235:genetics; D051155:Wnt1 Protein / Q000235:genetics / Q000378:metabolism*
chemical_list: D029721:Drosophila Proteins; D047908:Intracellular Signaling Peptides and Proteins; D034741:RNA, Small Interfering; C511046:Wls protein, Drosophila; D051153:Wnt Proteins; D051155:Wnt1 Protein; C074622:wg protein, Drosophila; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; C549822:Mop protein, Drosophila; D017027:Protein Tyrosine Phosphatases
keywords: Endosomal trafficking; Hrs; Myopic; Secretory pathway; Wnt/Wingless; Wntless