RT Journal
A1 Piegu, Benoit
A1 Guyot, Romain
A1 Picault, Nathalie
A1 Roulin, Anne
A1 Saniyal, Abhijit
A1 Kim, Hyeran
A1 Collura, Kristi
A1 Brar, Darshan S.
A1 Jackson, Scott
A1 Wing, Rod A.
A1 Panaud, Olivier
T1 Doubling genome size without polyploidization: Dynamics of retrotransposition-driven genomic expansions in Oryza australiensis, a wild relative of rice
JF Genome Research 
JO Genome Research 
YR 2006 
FD October 01 
VO 16 
IS 10 
SP 1262 
OP 1269 
DO 10.1101/gr.5290206 
UL http://genome.cshlp.org/content/16/10/1262.abstract 
AB Retrotransposons are the main components of eukaryotic genomes, representing up to 80% of some large plant genomes. These mobile elements transpose via a “copy and paste” mechanism, thus increasing their copy number while active. Their accumulation is now accepted as the main factor of genome size increase in higher eukaryotes, besides polyploidy. However, the dynamics of this process are poorly understood. In this study, we show that Oryza australiensis, a wild relative of the Asian cultivated rice O. sativa, has undergone recent bursts of three LTR-retrotransposon families. This genome has accumulated more than 90,000 retrotransposon copies during the last three million years, leading to a rapid twofold increase of its size. In addition, phenetic analyses of these retrotransposons clearly confirm that the genomic bursts occurred posterior to the radiation of the species. This provides direct evidence of retrotransposon-mediated variation of genome size within a plant genus.