TY  - JOUR
A1  - Bouneau, Laurence
A1  - Fischer, Cécile
A1  - Ozouf-Costaz, Catherine
A1  - Froschauer, Alexander
A1  - Jaillon, Olivier
A1  - Coutanceau, Jean-Pierre
A1  - Körting, Cornelia
A1  - Weissenbach, Jean
A1  - Bernot, Alain
A1  - Volff, Jean-Nicolas
T1  - An Active Non-LTR Retrotransposon With Tandem Structure in the Compact
 Genome of the Pufferfish Tetraodon nigroviridis
Y1  - 2003/07/01 
JF  - Genome Research 
JO  - Genome Research 
SP  - 1686 
EP  - 1695 
DO  - 10.1101/gr.726003 
VL  - 13 
IS  - 7 
UR  - http://genome.cshlp.org/content/13/7/1686.abstract 
N2  - The fish retrotransposable element Zebulon encodes a reverse
 transcriptase and a carboxy-terminal restriction enzyme-like endonuclease, and
 is related phylogenetically to site-specific non-LTR retrotransposons from
 nematodes. Zebulon was detected in the pufferfishes Tetraodon
 nigroviridis and Takifugu rubripes, as well as in the zebrafish
 Danio rerio. Structural analysis suggested that Zebulon, in
 contrast to most non-LTR retrotransposons, might be able to retrotranspose as
 a partial tandem array. Zebulon was active relatively recently in the
 compact genome of T. nigroviridis, in which it contributed to the
 extension of intergenic and intronic sequences, and possibly to the formation
 of genomic rearrangements. Accumulation of Zebulon together with
 other retrotransposons was observed in some heterochromatic chromosomal
 regions of the genome of T. nigroviridis that might serve as
 reservoirs for active elements. Hence, pufferfish compact genomes are not
 evolutionarily inert and contain active retrotransposons, suggesting the
 presence of mechanisms allowing accumulation of retrotransposable elements in
 heterochromatin, but minimizing their impact on euchromatic regions.
 Homologous recombination between partial tandem sequences eliminating active
 copies of Zebulon and reducing the size of insertions in intronic and
 intragenic regions might represent such a mechanism. 
ER  -