Large-Scale Phylogenomic Analysis Reveals the Complex Evolutionary History of Rabies Virus in Multiple Carnivore Hosts

Even genetically distant prokaryotes can exchange genes between them, and these horizontal gene transfer events play a central role in adaptation and evolution. While this was long thought to be restricted to prokaryotes, certain eukaryotes have acquired genes of bacterial origin. However, gene acquisitions in eukaryotes are thought to be much less important in magnitude than in prokaryotes. Here, we describe the complex evolutionary history of a bacterial catabolic gene that has been transferred repeatedly from different bacterial phyla to stramenopiles and fungi. Indeed, phylogenomic analysis pointed to multiple acquisitions of the gene in these filamentous eukaryotes—as many as 15 different events for 65 microeukaryotes. Furthermore, once transferred, this gene acquired introns and was found expressed in mRNA databases for most recipients. Our results show that effective inter-domain transfers and subsequent adaptation of a prokaryotic gene in eukaryotic cells can happen at an unprecedented magnitude.

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Genetic Diversity of Rice stripe necrosis virus and New Insights into Evolution of the Genus Benyvirus

Viruses ◽

10.3390/v13050737 ◽

2021 ◽

Vol 13 (5) ◽

pp. 737

Author(s):

Issiaka Bagayoko ◽

Marcos Giovanni Celli ◽

Gustavo Romay ◽

Nils Poulicard ◽

Agnès Pinel-Galzi ◽

...

Keyword(s):

Genetic Diversity ◽

Genetic Variability ◽

Sierra Leone ◽

Evolutionary History ◽

Molecular Diversity ◽

Genomic Data ◽

Gene Recombination ◽

Necrosis Virus ◽

History Of ◽

Complex Evolutionary History

The rice stripe necrosis virus (RSNV) has been reported to infect rice in several countries in Africa and South America, but limited genomic data are currently publicly available. Here, eleven RSNV genomes were entirely sequenced, including the first corpus of RSNV genomes of African isolates. The genetic variability was differently distributed along the two genomic segments. The segment RNA1, within which clusters of polymorphisms were identified, showed a higher nucleotidic variability than did the beet necrotic yellow vein virus (BNYVV) RNA1 segment. The diversity patterns of both viruses were similar in the RNA2 segment, except for an in-frame insertion of 243 nucleotides located in the RSNV tgbp1 gene. Recombination events were detected into RNA1 and RNA2 segments, in particular in the two most divergent RSNV isolates from Colombia and Sierra Leone. In contrast to BNYVV, the RSNV molecular diversity had a geographical structure with two main RSNV lineages distributed in America and in Africa. Our data on the genetic diversity of RSNV revealed unexpected differences with BNYVV suggesting a complex evolutionary history of the genus Benyvirus.

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Rhizobial plasmids — replication, structure and biological role

Open Life Sciences ◽

10.2478/s11535-012-0058-8 ◽

2012 ◽

Vol 7 (4) ◽

pp. 571-586 ◽

Cited By ~ 8

Author(s):

Andrzej Mazur ◽

Piotr Koper

Keyword(s):

Genome Organization ◽

Soil Bacteria ◽

Evolutionary History ◽

Bacterial Genome ◽

Biological Role ◽

Genome Architecture ◽

Genomic Knowledge ◽

History Of ◽

Cryptic Plasmids ◽

Complex Evolutionary History

AbstractSoil bacteria, collectively named rhizobia, can establish mutualistic relationships with legume plants. Rhizobia often have multipartite genome architecture with a chromosome and several extrachromosomal replicons making these bacteria a perfect candidate for plasmid biology studies. Rhizobial plasmids are maintained in the cells using a tightly controlled and uniquely organized replication system. Completion of several rhizobial genome-sequencing projects has changed the view that their genomes are simply composed of the chromosome and cryptic plasmids. The genetic content of plasmids and the presence of some important (or even essential) genes contribute to the capability of environmental adaptation and competitiveness with other bacteria. On the other hand, their mosaic structure results in the plasticity of the genome and demonstrates a complex evolutionary history of plasmids. In this review, a genomic perspective was employed for discussion of several aspects regarding rhizobial plasmids comprising structure, replication, genetic content, and biological role. A special emphasis was placed on current post-genomic knowledge concerning plasmids, which has enriched the view of the entire bacterial genome organization by the discovery of plasmids with a potential chromosome-like role.

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