Plant retroviruses: structure, evolution and future applications

Retroelements, which replicate by reverse transcription, have been detected in higher plants, higher animals, fungi, insects and bacteria. They have been classified into viral retroelements, eukaryotic chromosomal non-viral retroelements and bacterial chromosomal retroelements. Until recently, retroviruses were thought to be restricted to vertebrates. Plant sequencing projects revealed that plant genomes contain retroviral-like sequences. This review aims to address the structure and evolution of plant retroviruses. In addition, it proposes future applications for these important key components of plant genomes.