- THIS ARTICLE
- Full Text (PDF)
- Alert me when this article is cited
- Alert me if a correction is posted
- SERVICES
- Similar articles in this journal
- Similar articles in PubMed
- Alert me to new issues of the journal
- Download to citation manager
- Reprints & Permissions
- CITING ARTICLES
- Citing Articles via HighWire
- Citing Articles via Google Scholar
- GOOGLE SCHOLAR
- Articles by Eickbush, D. G.
- Articles by Eickbush, T. H.
- Search for Related Content
- PUBMED
- PubMed Citation
- Articles by Eickbush, D. G.
- Articles by Eickbush, T. H.
Genetics, Vol 139, 671-684, Copyright © 1995
INVESTIGATIONS |
Vertical Transmission of the Retrotransposable Elements R1 and R2 During the Evolution of the Drosophila melanogaster Species Subgroup
D. G. Eickbush and T. H. Eickbush
Department of Biology, University of Rochester, Rochester, New York 14627
R1 and R2 are non-long-terminal repeat retrotransposable elements that insert into specific sequences of insect 28S ribosomal RNA genes. These elements have been extensively described in Drosophila melanogaster. To determine whether these elements have been horizontally or vertically transmitted, we characterized R1 and R2 elements from the seven other members of the melanogaster species subgroup by genomic blotting and nucleotide sequencing. Each species was found to have homogeneous families of R1 and R2 elements with the exception of erecta and orena, which have no R2 elements. The DNA sequences of multiple R1 and R2 copies from each species indicated nucleotide divergence within each species averaged only 0.48% for R1 and 0.35% for R2, well below the level of divergence among the species. Most copies of R1 and R2 (40 of 47) sequenced from the seven species were potentially functional, as indicated by the absence of premature termination codons or translational frameshifts that would destroy the open reading frame of the element. The sequence relationships of both the R1 and R2 elements from the various members of the melanogaster subgroup closely followed that of the species phylogeny, suggesting that R1 and R2 have been stably maintained by vertical transmission since the origin of this species subgroup 17-20 million years ago. The remarkable stability of R1 and R2, compared to what has been suggested for transposable elements that insert at multiple locations in these same species, may be due to their unique specificity for sites in the rRNA gene locus. Under low copy number conditions, when it is essential for any mobile element to transpose, the insertion specificities of R1 and R2 ensure uniform developmentally regulated target sites that can be occupied with little or no detrimental effect on the host.
This article has been cited by other articles:
![]() |
X. Zhang, J. Zhou, and T. H. Eickbush Rapid R2 Retrotransposition Leads to the Loss of Previously Inserted Copies via Large Deletions of the rDNA Locus Mol. Biol. Evol., January 1, 2008; 25(1): 229 - 237. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. E. Stage and T. H. Eickbush Sequence variation within the rRNA gene loci of 12 Drosophila species Genome Res., December 1, 2007; 17(12): 1888 - 1897. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. K. Kojima, K.-i. Kuma, H. Toh, and H. Fujiwara Identification of rDNA-Specific Non-LTR Retrotransposons in Cnidaria Mol. Biol. Evol., October 1, 2006; 23(10): 1984 - 1993. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. T. Averbeck and T. H. Eickbush Monitoring the Mode and Tempo of Concerted Evolution in the Drosophila melanogaster rDNA Locus Genetics, December 1, 2005; 171(4): 1837 - 1846. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Zhang and T. H. Eickbush Characterization of Active R2 Retrotransposition in the rDNA Locus of Drosophila simulans Genetics, May 1, 2005; 170(1): 195 - 205. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. H. Penton and T. J. Crease Evolution of the Transposable Element Pokey in the Ribosomal DNA of Species in the Subgenus Daphnia (Crustacea: Cladocera) Mol. Biol. Evol., September 1, 2004; 21(9): 1727 - 1739. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. E. Perez-Gonzalez, W. D. Burke, and T. H. Eickbush R1 and R2 Retrotransposition and Deletion in the rDNA Loci on the X and Y Chromosomes of Drosophila melanogaster Genetics, October 1, 2003; 165(2): 675 - 685. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. G. Eickbush and T. H. Eickbush Transcription of Endogenous and Exogenous R2 Elements in the rRNA Gene Locus of Drosophila melanogaster Mol. Cell. Biol., June 1, 2003; 23(11): 3825 - 3836. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. E. Perez-Gonzalez and T. H. Eickbush Dynamics of R1 and R2 Elements in the rDNA Locus of Drosophila simulans Genetics, August 1, 2001; 158(4): 1557 - 1567. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Langdon, C. Seago, M. Mende, M. Leggett, H. Thomas, J. W. Forster, H. Thomas, R. N. Jones, and G. Jenkins Retrotransposon Evolution in Diverse Plant Genomes Genetics, September 1, 2000; 156(1): 313 - 325. [Abstract] [Full Text] |
||||
![]() |
D. G. Eickbush, D. D. Luan, and T. H. Eickbush Integration of Bombyx mori R2 Sequences into the 28S Ribosomal RNA Genes of Drosophila melanogaster Mol. Cell. Biol., January 1, 2000; 20(1): 213 - 223. [Abstract] [Full Text] |
||||
![]() |
H. S. Malik and T. H. Eickbush NeSL-1, an Ancient Lineage of Site-Specific Non-LTR Retrotransposons From Caenorhabditis elegans Genetics, January 1, 2000; 154(1): 193 - 203. [Abstract] [Full Text] |
||||
![]() |
H. S. Malik and T. H. Eickbush Retrotransposable Elements R1 and R2 in the rDNA Units of Drosophila mercatorum: abnormal abdomen Revisited Genetics, February 1, 1999; 151(2): 653 - 665. [Abstract] [Full Text] |
||||
![]() |
D. Kordis and F. Gubensek Unusual horizontal transfer of a long interspersed nuclear element between distant vertebrate classes PNAS, September 1, 1998; 95(18): 10704 - 10709. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Yang and T. H. Eickbush RNA-Induced Changes in the Activity of the Endonuclease Encoded by the R2 Retrotransposable Element Mol. Cell. Biol., June 1, 1998; 18(6): 3455 - 3465. [Abstract] [Full Text] |
||||




