Transposition-mediated DNA re-replication in maize

• DOI: 10.7554/elife.03724
• Publication Date: 2014-11-18T12:32:42Z
• Authors: Jianbo Zhang; Tao Zuo; Dafang Wang; Thomas Peterson
• Keywords: DNA Replication; 570; DNA End-Joining Repair; DNA, Plant; QH301-705.5; composite insertion; Science; DNA replication; maize; Polymerase Chain Reaction; Zea mays; 03 medical and health sciences; Agronomy and Crop Sciences; Gene Duplication; transposition; Biology (General); Base Pairing; Alleles; Recombination, Genetic; 2. Zero hunger; 0303 health sciences; 000; Models, Genetic; Q; R; Genetics and Genomics; Plant Breeding and Genetics; Ac/D; Mutagenesis, Insertional; duplication; Genes and Chromosomes; Genetic Loci; DNA Transposable Elements; Medicine; Genome, Plant

Every DNA segment in a eukaryotic genome normally replicates once and only once per cell cycle to maintain genome stability. We show here that this restriction can be bypassed through alternative transposition, a transposition reaction that utilizes the termini of two separate, nearby transposable elements (TEs). Our results suggest that alternative transposition during S phase can induce re-replication of the TEs and their flanking sequences. The DNA re-replication can spontaneously abort to generate double-strand breaks, which can be repaired to generate Composite Insertions composed of transposon termini flanking segmental duplications of various lengths. These results show how alternative transposition coupled with DNA replication and repair can significantly alter genome structure and may have contributed to rapid genome evolution in maize and possibly other eukaryotes.