What is retrotransposon?
Transposons are pieces of DNA that are mobile or can move to different places within genetic information about the cell. Moving to a new place in the cell genome can cause transposons to cause mutations, and also to change the amount of DNA found in the cell. They are also referred to as jumping genes and are grouped into two categories that are class II transposons and class I or retrotransposons. The difference between the two classes is related to how they move; Retrotransposon has a two -stage movement process.
The way of moving the DNA segment is the way transposons are classified into each category. Class II transposon is a piece of bottom that moves from one place to another. Movement of class I transposon or retrotransposon is much more complicated and includes two steps to move the DNA segment. RNA can now move freely throughout the genome because it is not tied to the DNA spring. When RNA reaches a new location, a specific enzyme, called reverse transcriptaseA, creates a new spring of DNA based on the RNA segment. This new piece of DNA is then attached to a new location in the genome.
When retrotransposon is rewritten back to DNA segment from a copy of RNA, it usually has a long terminal repetition at the end of the DNA sequence (LTR). LTRs consist of recurring foundations sequences that can be hundreds or even thousands of foundations. They usually surround the functional part of the DNA, such as the gene, and are necessary to connect the DNA segment to the original DNA chain. LTRs are one way scientists can recognize that part of the DNA contains retrotransposon. It is assumed that about 42% of the whole human genome is formed by retrotremansposons.
Since new DNA copies are made through reverse RNA transcription, the addition of retrotransposone is a way to increase the amount of DNA found in one cell. If retrotransposon is inserted into a gene or near the gene, cane to cause a mutation. Mutations are essentially changes in DNA sequence and can have positive, negative or no impact on the genome, depending on how DNA sequence changes.