title: Differences in the secretion and transport of Wnt proteins.
abstract: During the last three decades, our understanding about Wnt signaling has progressed greatly, especially with regards to the molecular mechanism of intracellular transmission of this signaling, as well as its physiological roles. In parallel, the molecular nature of Wnt proteins has gradually but surely been clarified. Wnt proteins are post-translationaly modified with fatty acid and glycosaminoglycans, resulting in constraint of the 3D structure and behavior of the proteins. Specific binding proteins or extracellular vesicles, which appear to shield the lipid moiety from the aquatic environment, enable Wnt proteins to be transported in the extracellular space. Equally, Wnt-interacting proteins in the extracellular space, including heparan sulfate proteoglycan, are also involved in its spreading. Recent studies also show that intercellular transmission of Wnt proteins occurs by cell migration and extension of cell protrusions. Here, we will show the molecular and cellular bases of the trafficking of Wnt proteins and discuss questions that remain to be answered.
authors.affiliation: Okazaki Institute for Integrative Bioscience stakada@nibb.ac.jp.|National Institute for Basic Biology, National Institutes of Natural Sciences.|The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi 444-8787, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Takada
authors.affiliation: Okazaki Institute for Integrative Bioscience.|National Institute for Basic Biology, National Institutes of Natural Sciences.
authors.forename: Sayumi
authors.initials: S
authors.lastname: Fujimori
authors.affiliation: Okazaki Institute for Integrative Bioscience.|National Institute for Basic Biology, National Institutes of Natural Sciences.|The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi 444-8787, Japan.
authors.forename: Takuma
authors.initials: T
authors.lastname: Shinozuka
authors.affiliation: Okazaki Institute for Integrative Bioscience.|National Institute for Basic Biology, National Institutes of Natural Sciences.
authors.forename: Ritsuko
authors.initials: R
authors.lastname: Takada
authors.affiliation: Okazaki Institute for Integrative Bioscience.|National Institute for Basic Biology, National Institutes of Natural Sciences.|The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi 444-8787, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Mii
mesh_terms: D000818:Animals; D006801:Humans; D000072417:Protein Domains; D021381:Protein Transport / Q000502:physiology; D013329:Structure-Activity Relationship; D051153:Wnt Proteins / Q000737:chemistry / Q000378:metabolism*; D060449:Wnt Signaling Pathway / Q000502:physiology*
chemical_list: D051153:Wnt Proteins
keywords: Wnt; cytoneme; extracellular vesicles; heparan sulfate; lipidation; secretione