title: Expression of Active Fluorophore Proteins in the Milk of Transgenic Pigs Bypassing the Secretory Pathway.
abstract: We describe the expression of recombinant fluorescent proteins in the milk of two lines of transgenic pigs generated by Sleeping Beauty transposon-mediated genetic engineering. The Sleeping Beauty transposon consisted of an ubiquitously active CAGGS promoter driving a fluorophore cDNA, encoding either Venus or mCherry. Importantly, the fluorophore cDNAs did not encode for a signal peptide for the secretory pathway, and in previous studies of the transgenic animals a cytoplasmic localization of the fluorophore proteins was found. Unexpectedly, milk samples from lactating sows contained high levels of bioactive Venus or mCherry fluorophores. A detailed analysis suggested that exfoliated cells of the mammary epithelium carried the recombinant proteins passively into the milk. This is the first description of reporter fluorophore expression in the milk of livestock, and the findings may contribute to the development of an alternative concept for the production of bioactive recombinant proteins in the udder.
authors.affiliation: Friedrich-Loeffler-Institut, Institut für Nutztiergenetik, Mariensee, Germany.
authors.forename: Ayan
authors.initials: A
authors.lastname: Mukherjee
authors.affiliation: Medical School Hannover, Institute of Laboratory Animal Sciences, Hannover, Germany.
authors.forename: Wiebke
authors.initials: W
authors.lastname: Garrels
authors.affiliation: Friedrich-Loeffler-Institut, Institut für Nutztiergenetik, Mariensee, Germany.
authors.forename: Thirumala R
authors.initials: TR
authors.lastname: Talluri
authors.affiliation: Friedrich-Loeffler-Institut, Institut für Nutztiergenetik, Mariensee, Germany.
authors.forename: Daniela
authors.initials: D
authors.lastname: Tiedemann
authors.affiliation: NARIC- Agricultural Biotechnology Institute, Gödöllö, Hungary.
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Bősze
authors.affiliation: Paul-Ehrlich-Institute, Langen, Germany.
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Ivics
authors.affiliation: Friedrich-Loeffler-Institut, Institut für Nutztiergenetik, Mariensee, Germany.
authors.forename: Wilfried A
authors.initials: WA
authors.lastname: Kues
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D004251:DNA Transposable Elements; D004847:Epithelial Cells / Q000378:metabolism*; D005260:Female; D049452:Green Fluorescent Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008164:Luminescent Proteins / Q000235:genetics* / Q000378:metabolism; D042361:Mammary Glands, Human / Q000166:cytology / Q000378:metabolism; D008892:Milk / Q000166:cytology* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D021382:Protein Sorting Signals; D055571:Secretory Pathway; D013552:Swine; D000097573:Red Fluorescent Protein
chemical_list: D004251:DNA Transposable Elements; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins; D021382:Protein Sorting Signals; D000097573:Red Fluorescent Protein