title: Measuring in vivo protein half-life.
abstract: Protein turnover critically influences many biological functions, yet methods have been lacking to assess this parameter in vivo. Here, we demonstrate how chemical labeling of SNAP-tag fusion proteins can be exploited to measure the half-life of resident intracellular and extracellular proteins in living mice. First, we demonstrate that SNAP-tag substrates have wide bioavailability in mice and can be used for the specific in vivo labeling of SNAP-tag fusion proteins. We then apply near-infrared probes to perform noninvasive imaging of in vivo-labeled tumors. Finally, we use SNAP-mediated chemical pulse-chase labeling to perform measurement of the in vivo half-life of different extra- and intracellular proteins. These results open broad perspectives for studying protein function in living animals.
authors.affiliation: School of Life Sciences, Frontiers-in-Genetics National Program, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
authors.forename: Karolina
authors.initials: K
authors.lastname: Bojkowska
authors.forename: Francesca
authors.initials: F
authors.lastname: Santoni de Sio
authors.forename: Isabelle
authors.initials: I
authors.lastname: Barde
authors.forename: Sandra
authors.initials: S
authors.lastname: Offner
authors.forename: Sonia
authors.initials: S
authors.lastname: Verp
authors.forename: Christian
authors.initials: C
authors.lastname: Heinis
authors.forename: Kai
authors.initials: K
authors.lastname: Johnsson
authors.forename: Didier
authors.initials: D
authors.lastname: Trono
mesh_terms: D000818:Animals; D015704:CD4 Antigens / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D005456:Fluorescent Dyes / Q000737:chemistry; D006207:Half-Life; D051379:Mice; D008819:Mice, Nude; D008822:Mice, Transgenic; D019853:O(6)-Methylguanine-DNA Methyltransferase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D055550:Protein Stability; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D015704:CD4 Antigens; D005456:Fluorescent Dyes; D011993:Recombinant Fusion Proteins; D019853:O(6)-Methylguanine-DNA Methyltransferase