Intrachromatide homologous recombination

The elimination of LTR retrotransposon sequences in plants is the result of several cellular processes such as homologous recombination (leading to the formation of solo LTRs), and the accumulation of small deletions through illegitimate recombination [Vitte07].This process involves recombination mechanisms that occur either between the LTRs of the elements, leading to the formation of solo-LTRs, or between direct repeats anywhere in the sequence of the element, leading to internal deletions. All these studies have led to the emergence of a new model for plant genome evolution that takes into account both genome size increases (through retrotransposition) and decreases (through solo-LTR and deletion formation) (the increase/decrease model Vitte and Panaud, 2005).