title: Host-virus shift of the sphingolipid pathway along an Emiliania huxleyi bloom: survival of the fattest.
abstract: The interactions between viruses and phytoplankton play a key role in shaping the ecological and evolutionary dynamics of oceanic ecosystems. One of the most fascinating examples of horizontal gene transfer between a eukaryotic host and its virus is a de novo sphingolipid biosynthesis pathway (SBP) found in the genomes of both Emiliania huxleyi and its coccolithovirus EhV-86. Here, we focus on a natural E. huxleyi/coccolithovirus system off the coast of Norway and investigate the dynamics of host and virus homologous gene expression for two of the most important sphingolipid biosynthesis enzymes, serine palmitoyl transferase (SPT) and dihydroceramide desaturase (DCD). Transcriptional dynamics display three defined stages along E. huxleyi bloom formation and decline, with the coccolithovirus transcripts taking over and controlling the SBP in stages 2 and 3. The observed patterns fit the hypothesis according to which viral sphingolipids are involved in the timing and physical processes of virion release from the host cells. This study provides a unique insight into the transcriptional interplay of homologous metabolic pathways between virus and host during temporal progression of oceanic E. huxleyi blooms.
authors.affiliation: UPMC Univ. Paris 06, UMR 7144, Equipe EPPO: Evolution du Plancton et PaléoOcéans, Station Biologique de Roscoff, 29682 Roscoff, France.
authors.forename: António
authors.initials: A
authors.lastname: Pagarete
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Allen
authors.forename: William H
authors.initials: WH
authors.lastname: Wilson
authors.forename: Susan A
authors.initials: SA
authors.lastname: Kimmance
authors.forename: Colomban
authors.initials: C
authors.lastname: de Vargas
mesh_terms: D053898:Biosynthetic Pathways / Q000235:genetics*; D048028:DNA, Algal / Q000737:chemistry / Q000235:genetics; D020869:Gene Expression Profiling; D022761:Gene Transfer, Horizontal; D008969:Molecular Sequence Data; D009664:Norway; D010088:Oxidoreductases / Q000096:biosynthesis / Q000235:genetics; D017862:Phycodnaviridae / Q000235:genetics*; D010839:Phytoplankton / Q000378:metabolism* / Q000821:virology*; D017422:Sequence Analysis, DNA; D051102:Serine C-Palmitoyltransferase / Q000096:biosynthesis / Q000235:genetics; D013107:Sphingolipids / Q000096:biosynthesis*; D014871:Water Microbiology
chemical_list: D048028:DNA, Algal; D013107:Sphingolipids; D010088:Oxidoreductases; C108138:dihydroceramide desaturase; D051102:Serine C-Palmitoyltransferase