  Transposable elements, or transposons, are DNA sequences that can jump from
site to site in the genome during the life cycle of a cell, usually encoding
the very enzymes which perform their excision. However, some transposons are
parasitic, relying on the enzymes produced by the regular transposons. In this
case, we show that a stochastic model, which takes into account the small copy
numbers of the transposons in a cell, predicts noise-induced predator-prey
oscillations with a characteristic time scale that is much longer than the cell
replication time, indicating that the state of the predator-prey oscillator is
stored in the genome and transmitted to successive generations. Our work
demonstrates the important role of number fluctuations in the expression of
mobile genetic elements, and shows explicitly how ecological concepts can be
applied to the dynamics and fluctuations of living genomes.
