Elements that are transcribed into RNA,reverse-transcribed into DNA and then inserted into a new site in the genome. Long terminal repeats (LTRs) similar to those from retroviruses are contained in retrotransposons and retrovirus-like elements. Retroposons,such as LONG INTERSPERSED NUCLEOTIDE ELEMENTS and SHORT INTERSPERSED NUCLEOTIDE ELEMENTS do not contain LTRs.
- Interestingly, it was recently found that specific LINE-1 retroposons in the human genome are actively transcribed and the associated LINE-1 RNAs are tightly bound to nucleosomes and essential in the establishment of local chromatin environment.
- The group was proposed following an alignment of nuclear intron sequences by Shannon Hackett et al . in 2008, it was formally named in a 2011 " Nature Communications " article by Alexander Suh and other authors working with J�rgen Schmitz's group, based on genetic analysis of the insertion of retroposons into the genomes of key avian lineages over the course of evolution during the Mesozoic Era.