What is the origin and function of transposons? I came across them in my work and it was never really clear what they were. Any description no matter how vague or specific is appreciated. Thank you for your time and effort
Genomes' evolution mostly relies on transposable elements, or transposons, which are DNA sequences that have the capacity to migrate from one location to other location, inside the genome. All organisms, prokaryotic and eukaryotic, posses transposable elements which occupy a large percentage the species' genome. Since genome's volume is mostly occupied by transposable elements, then it is supposed that transposons have changed the genome size, although the cause that led to amplification of transposable elements is not quite clear.
The genes may be altered by DNA transposons which are able to enter within exons, introns or regulatory regions. Sometimes, transposons were taught by the host to do a particular function within the cell.
The movement of transposons follows the mechanism known as cut and paste, being removed from one site and restored in other location. There exists two classes of transposons and in both of them, there are found non-autonomous elements, depending on autonomous transposons.
Transposons and transposition process can be harmful for the host and it is indicated to find strategies for controlling transposons, in order to protect both, the host and transposons that depend on the host's survival.