title: Use of a molecular genetic platform technology to produce human Wnt proteins reveals distinct local and distal signaling abilities.
abstract: Functional and mechanistic studies of Wnt signaling have been severely hindered by the inaccessibility of bioactive proteins. To overcome this long-standing barrier, we engineered and characterized a panel of Chinese hamster ovary (CHO) cell lines with inducible transgenes encoding tagged and un-tagged human WNT1, WNT3A, WNT5A, WNT7A, WNT11, WNT16 or the soluble Wnt antagonist Fzd8CRD, all integrated into an identical genomic locus. Using a quantitative real-time bioluminescence assay, we show that cells expressing WNT1, 3A and 7A stimulate Wnt/beta-catenin reporter activity, while the other WNT expressing cell lines interfere with this activation. Additionally, in contrast to WNT3A, WNT1 only exhibits activity when cell-associated, and thus only signals to neighboring cells. The reporter assay also revealed a rapid decline of Wnt activity at 37°C, indicating that Wnt activity is highly labile. These engineered cell lines will reduce the cost of making and purifying Wnt proteins and serve as a continuous, reliable and regulatable source of Wnts to research laboratories around the world.
authors.affiliation: The Salk Institute for Biological Studies, La Jolla, California, USA.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Green
authors.forename: Matthieu
authors.initials: M
authors.lastname: Bauer
authors.forename: Kyu Won
authors.initials: KW
authors.lastname: Yum
authors.forename: Yao-Cheng
authors.initials: YC
authors.lastname: Li
authors.forename: Miranda L
authors.initials: ML
authors.lastname: Cox
authors.forename: Karl
authors.initials: K
authors.lastname: Willert
authors.forename: Geoffrey M
authors.initials: GM
authors.lastname: Wahl
mesh_terms: D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D015870:Gene Expression; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D051153:Wnt Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D060449:Wnt Signaling Pathway
chemical_list: D011994:Recombinant Proteins; D051153:Wnt Proteins