生物谷报道：人们知道，细菌和它们的病毒（或噬菌体）之间的相互作用能导致宿主和噬菌体之间一定程度的共同演化。通过对在感染过程中海洋藻青菌Prochlorococcus及其T7一样的噬藻体（cyanophage）进行全基因组表达分析，研究人员对这种关系的亲近程度有了一个整体认识。在噬藻体感染过程中，若干个宿主基因得到协调的表达，该噬藻体则似乎能够很好地利用基因产物。这些藻青菌在海洋中普遍存在，并且在它们自己的小环境中居支配地位。
原始出处:
Nature 449, 83-86 (6 September 2007) | doi:10.1038/nature06130; Received 5 June 2007; Accepted 26 July 2007
Genome-wide expression dynamics of a marine virus and host reveal features of co-evolution
Debbie Lindell1,7, Jacob D. Jaffe3,7, Maureen L. Coleman1, Matthias E. Futschik5, Ilka M. Axmann5, Trent Rector4, Gregory Kettler1, Matthew B. Sullivan1, Robert Steen4, Wolfgang R. Hess6, George M. Church3 & Sallie W. Chisholm1,2
Department of Civil and Environmental Engineering,
Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
Department of Genetics, and,
BioPolymers Facility, Department of Genetics Harvard Medical School, Boston, Massachusetts 02115, USA
Institute for Theoretical Biology, Humboldt University, Berlin 10115, Germany
Institute of Biology, University of Freiburg, Freiburg 79104, Germany
Present addresses: Department of Biology, Technion—Israel Institute of Technology, Haifa 32000, Israel (D.L.); The Broad Institute of Harvard and MIT, Cambridge, Massachusetts 02141, USA (J.D.J).
Correspondence to: Sallie W. Chisholm1,2 Correspondence and requests for materials should be addressed to S.W.C. (Email: chisholm@mit.edu).
Interactions between bacterial hosts and their viruses (phages) lead to reciprocal genome evolution through a dynamic co-evolutionary process1, 2, 3, 4, 5. Phage-mediated transfer of host genes—often located in genome islands—has had a major impact on microbial evolution1, 4, 6. Furthermore, phage genomes have clearly been shaped by the acquisition of genes from their hosts2, 3, 5. Here we investigate whole-genome expression of a host and phage, the marine cyanobacterium Prochlorococcus MED4 and the T7-like cyanophage P-SSP7, during lytic infection, to gain insight into these co-evolutionary processes. Although most of the phage genome was linearly transcribed over the course of infection, four phage-encoded bacterial metabolism genes formed part of the same expression cluster, even though they are physically separated on the genome. These genes—encoding photosystem II D1 (psbA), high-light inducible protein (hli), transaldolase (talC) and ribonucleotide reductase (nrd)—are transcribed together with phage DNA replication genes and seem to make up a functional unit involved in energy and deoxynucleotide production for phage replication in resource-poor oceans. Also unique to this system was the upregulation of numerous genes in the host during infection. These may be host stress response genes and/or genes induced by the phage. Many of these host genes are located in genome islands and have homologues in cyanophage genomes. We hypothesize that phage have evolved to use upregulated host genes, leading to their stable incorporation into phage genomes and their subsequent transfer back to hosts in genome islands. Thus activation of host genes during infection may be directing the co-evolution of gene content in both host and phage genomes.
