PUBLICATION
Homologs of Drosophila P Transposons Were Mobile in Zebrafish but Have Been Domesticated in a Common Ancestor of Chicken and Human
- Authors
- Hammer, S.E., Strehl, S., and Hagemann, S.
- ID
- ZDB-PUB-041228-17
- Date
- 2005
- Source
- Mol. Biol. Evol. 22(4): 833-844 (Journal)
- Registered Authors
- Keywords
- Drosophila P transposons; Homo sapiens; Danio rerio; Gallus gallus; THAP proteins; molecular domestication
- MeSH Terms
-
- Amino Acid Sequence
- Animals
- Base Sequence
- Chickens/genetics*
- DNA Primers
- DNA Transposable Elements*
- Genome
- Humans
- In Situ Hybridization, Fluorescence
- Molecular Sequence Data
- Phylogeny
- Polymerase Chain Reaction
- Sequence Homology, Amino Acid
- Zebrafish/genetics*
- PubMed
- 15616143 Full text @ Mol. Biol. Evol.
Citation
Hammer, S.E., Strehl, S., and Hagemann, S. (2005) Homologs of Drosophila P Transposons Were Mobile in Zebrafish but Have Been Domesticated in a Common Ancestor of Chicken and Human. Mol. Biol. Evol.. 22(4):833-844.
Abstract
A substantial fraction of vertebrate and invertebrate genomes is composed of mobile elements and their derivatives. One of the most intensively studied transposon families, the P elements of Drosophila, was thought to exist exclusively in the genomes of dipteran insects. Based on the data provided by the human genome project, in 2001 our group has identified a P element-homologous sequence in the human genome. This P element-homologous human gene, named Phsa, is 19,533 nucleotides long, comprises 6 exons and 5 introns, and encodes a protein of still unknown function with a length of 903 amino acid residues. The N-terminal THAP domain of the putative Phsa protein shows similarities to the site-specific DNA-binding domain of the Drosophila P element transposase. In the present study, FISH analysis and the screening of a human lambda genomic library revealed a single copy of Phsa located on the long arm of chromosome 4, upstream of a gene coding for the hypothetical protein DKFZp686L1814. The same gene arrangement was found for the homologous gene Pgga in the genome of chicken, thus displaying Pgga at orthologous position on the long arm of chromosome 4. The single-copy gene status as well as the absence of terminal inverted repeats and target site duplications indicates that Phsa and Pgga constitute domesticated stationary sequences. In contrast, a considerable number of P-homologous sequences with terminal inverted repeats and intact target site duplications could be identified in zebrafish strongly indicating that Pdre elements were mobile within the zebrafish genome. Pdre elements are the first P-like transposons identified in a vertebrate species. With respect to Phsa, gene expression studies showed that Phsa is expressed in a broad range of human tissues suggesting that the putative Phsa protein plays a not yet understood but essential role in a specific metabolic pathway. We demonstrate that P-homologous DNA sequences occur in the genomes of 21 analyzed vertebrates but only as rudiments in the rodents. Finally, the evolutionary history of P element-homologous vertebrate sequences is discussed in the context of the "molecular domestication" hypothesis versus the "source gene hypothesis".
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping