title: Transcriptome dynamics of a broad host-range cyanophage and its hosts.
abstract: Cyanobacteria are highly abundant in the oceans and are constantly exposed to lytic viruses. The T4-like cyanomyoviruses are abundant in the marine environment and have broad host-ranges relative to other cyanophages. It is currently unknown whether broad host-range phages specifically tailor their infection program for each host, or employ the same program irrespective of the host infected. Also unknown is how different hosts respond to infection by the same phage. Here we used microarray and RNA-seq analyses to investigate the interaction between the Syn9 T4-like cyanophage and three phylogenetically, ecologically and genomically distinct marine Synechococcus strains: WH7803, WH8102 and WH8109. Strikingly, Syn9 led a nearly identical infection and transcriptional program in all three hosts. Different to previous assumptions for T4-like cyanophages, three temporally regulated gene expression classes were observed. Furthermore, a novel regulatory element controlled early-gene transcription, and host-like promoters drove middle gene transcription, different to the regulatory paradigm for T4. Similar results were found for the P-TIM40 phage during infection of Prochlorococcus NATL2A. Moreover, genomic and metagenomic analyses indicate that these regulatory elements are abundant and conserved among T4-like cyanophages. In contrast to the near-identical transcriptional program employed by Syn9, host responses to infection involved host-specific genes primarily located in hypervariable genomic islands, substantiating islands as a major axis of phage-cyanobacteria interactions. Our findings suggest that the ability of broad host-range phages to infect multiple hosts is more likely dependent on the effectiveness of host defense strategies than on differential tailoring of the infection process by the phage.
authors.affiliation: Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Shany
authors.initials: S
authors.lastname: Doron
authors.affiliation: Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Ayalla
authors.initials: A
authors.lastname: Fedida
authors.affiliation: Faculty of Sciences and Technology, University of Algarve, Faro, Portugal.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Hernández-Prieto
authors.affiliation: Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Gazalah
authors.initials: G
authors.lastname: Sabehi
authors.affiliation: Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Iris
authors.initials: I
authors.lastname: Karunker
authors.affiliation: Faculty of Biology, University of Freiburg, Freiburg, Germany.
authors.forename: Damir
authors.initials: D
authors.lastname: Stazic
authors.affiliation: Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Roi
authors.initials: R
authors.lastname: Feingersch
authors.affiliation: Faculty of Biology, University of Freiburg, Freiburg, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Steglich
authors.affiliation: Faculty of Sciences and Technology, University of Algarve, Faro, Portugal.|Centre of Marine Sciences, University of Algarve, Faro, Portugal.
authors.forename: Matthias
authors.initials: M
authors.lastname: Futschik
authors.affiliation: Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Debbie
authors.initials: D
authors.lastname: Lindell
authors.affiliation: Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Rotem
authors.initials: R
authors.lastname: Sorek
mesh_terms: D001435:Bacteriophages / Q000235:genetics* / Q000502:physiology; D020869:Gene Expression Profiling; D058507:Host Specificity; D056186:Metagenomics; D009792:Oceans and Seas; D020411:Oligonucleotide Array Sequence Analysis; D010802:Phylogeny; D048929:Prochlorococcus / Q000235:genetics / Q000821:virology*; D016415:Sequence Alignment; D017423:Sequence Analysis, RNA; D046940:Synechococcus / Q000235:genetics / Q000821:virology*; D059467:Transcriptome