Selfish DNA and the Origin of Genes

  title={Selfish DNA and the Origin of Genes},
  author={Donard S. Dwyer},
  pages={252 - 253}
  • D. Dwyer
  • Published 12 January 2001
  • Biology
  • Science
A palindromic repeat of about 150 base pairs was found by H. Ogata and colleagues to be inserted into many protein-coding genes of Rickettsia conorii , the bacterium that causes Mediterranean spotted fever (Reports, 13 Oct., p. [347][1]). The corresponding amino acids encoded by these repeats are 
Protein coding palindromes are a unique but recurrent feature in Rickettsia.
This comprehensive study of Rickettsia repeats confirms and extends previous observations and further indicates a significant role of selfish DNAs in the creation and modification of proteins.
Mechanisms of Evolution in Rickettsia conorii and R. prowazekii
The 1,268,755-nucleotide complete genome sequence of Rickettsia conorii is determined, containing 1374 open reading frames, and this genome exhibits 804 of the 834 genes of the previously determined R. prowazekii genome plus 552 supplementaryOpen reading frames and a 10-fold increase in the number of repetitive elements.
Miniature repetitive mobile elements of bacteria: Structural organization and properties
  • T. Ilyina
  • Biology
    Molecular Genetics, Microbiology and Virology
  • 2010
Data on miniature repetitive transposable elements containing inverted repeat sequences and a number of DNA motifs, such as host factor integration sites, transcription initiation boxes, as well as
Traffic at the tmRNA Gene
A partial screen for genetic elements integrated into completely sequenced bacterial genomes shows more significant bias in specificity for the tmRNA gene (ssrA) than for any type of tRNA gene, suggesting the evolution of new site specificity by integrases may be as strong as toward a tRNA-like sequence.
Proliferation and deterioration of Rickettsia palindromic elements.
The phylogenetic depth of two RPEs that are located close to the genes encoding elongation factors Tu (tuf) and G (fus) in Rickettsia are examined, providing evidence for independent loss of RPE-tuf in several species, possibly mediated by short repetitive sequences flanking the site of excision.
Variations on the tmRNA gene
A native bacterial sSRA disrupted by insertion of a genomic island that carries its own ssrA is described, a genome encoding both one- and two-piece tmRNAs, and a phage encoding a tmRNA variant lacking the mRNA-like function, which may counteract host tm RNA during infection.
Characterization of a tandem repeat polymorphism in Rickettsia strains.
PCR amplification of the Rc-65 locus can be used to differentiate between the Portuguese R. conorii Malish-like and Israeli tick typhus strains, enabling a more accurate and rapid identification of these rickettsial isolates.
rRNA Intergenic Spacer Regions for Phylogenetic Analysis of Rickettsia Species
Phylogenetic trees inferred from rrl‐rrf spacer sequences using maximum‐parsimony and distance methods provided largely congruent tree topologies, supported by significant bootstrap values, enabling the identification of five distinct rickettsiae clusters.
Phylogeny and Comparative Genomics: the Shifting Landscape in the Genomics Era
A robust phylogeny based on whole-genome sequences supports the current taxonomic delineations within the Anaplasmataceae and Rickettsiaceae, with monophyly of each of the six genera strongly supported.
Application of quantitative measures of gene order similarity to phylogenetic reconstructions (exemplified by bacteria of the genus Rickettsia)
It is shown that phylogenetic reconstructions based on quantitative estimates of the similarity and cladistic analysis of gene order data, may amend and fill up classical phylogenetic trees, and substantiate the hypothesis that Rickettsia felis species had split before the typhus, spotted fever and spotted fever groups.


Selfish DNA in protein-coding genes of Rickettsia.
The finding of a mobile element inserted in many unrelated genes suggests the potential role of selfish DNA in the creation of new protein sequences in R. conorii.
tmRNAs that encode proteolysis-inducing tags are found in all known bacterial genomes: A two-piece tmRNA functions in Caulobacter.
Although several sequence and structural motifs that are conserved among one-piece tmRNAs have been lost, the alpha-proteobacterium Caulobacter crescentus produces a functional two- piece tmRNA.
Assembly of exons from unitary transposable genetic elements: implications for the evolution of protein-protein interactions.
  • D. Dwyer
  • Biology
    Journal of theoretical biology
  • 1998
It has been proposed that peptides encoded by the first trexons were predisposed to form dimers or oligomers, and detailed structural analysis of various protein-protein complexes has revealed a tendency for the duplication units to self-associate.