title: Lipid droplet biology and evolution illuminated by the characterization of a novel perilipin in teleost fish.
abstract: Perilipin (PLIN) proteins constitute an ancient family important in lipid droplet (LD) formation and triglyceride metabolism. We identified an additionalPLINclade (plin6) that is unique to teleosts and can be traced to the two whole genome duplications that occurred early in vertebrate evolution. Plin6 is highly expressed in skin xanthophores, which mediate red/yellow pigmentation and trafficking, but not in tissues associated with lipid metabolism. Biochemical and immunochemical analyses demonstrate that zebrafish Plin6 protein targets the surface of pigment-containing carotenoid droplets (CD). Protein kinase A (PKA) activation, which mediates CD dispersion in xanthophores, phosphorylates Plin6 on conserved residues. Knockout ofplin6in zebrafish severely impairs the ability of CD to concentrate carotenoids and prevents tight clustering of CD within carotenoid bodies. Ultrastructural and functional analyses indicate that LD and CD are homologous structures, and that Plin6 was functionalized early in vertebrate evolution for concentrating and trafficking pigment.
authors.affiliation: Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, United States.
authors.forename: James G
authors.initials: JG
authors.lastname: Granneman
authors.affiliation: Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, United States.
authors.forename: Vickie A
authors.initials: VA
authors.lastname: Kimler
authors.affiliation: Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, United States.
authors.forename: Huamei
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, United States.
authors.forename: Xiangqun
authors.initials: X
authors.lastname: Ye
authors.affiliation: Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, United States.|Department of Ophthalmology, Wayne State University School of Medicine, Detroit, United States.
authors.forename: Xixia
authors.initials: X
authors.lastname: Luo
authors.affiliation: Institute of Neuroscience, University of Oregon, Eugene, United States.|Department of Biology, University of Oregon, Eugene, United States.
authors.forename: John H
authors.initials: JH
authors.lastname: Postlethwait
authors.affiliation: Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, United States.|Department of Ophthalmology, Wayne State University School of Medicine, Detroit, United States.
authors.forename: Ryan
authors.identifier: 0000-0002-0522-8704
authors.initials: R
authors.lastname: Thummel
mesh_terms: D000818:Animals; D002338:Carotenoids / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D020869:Gene Expression Profiling; D055786:Gene Knockout Techniques; D066292:Lipid Droplets / Q000378:metabolism*; D000070778:Perilipin-1 / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D015027:Zebrafish
chemical_list: D000070778:Perilipin-1; D002338:Carotenoids; D017868:Cyclic AMP-Dependent Protein Kinases
keywords: carotenoid; cell biology; evolutionary biology; genomics; lipid; perilipin; spotted gar; teleost; xanthophore; zebrafish