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Anthology of Human Repetitive DNA
Retrotransposon (Retroposon)
A transposable element that is reproduced via reverse transcription of an RNA
intermediate. They can be split into two classes: LTR and non-LTR retrotransposons.
Retrovirus
An RNA virus, whose life cycle includes cytoplasmic reverse transcription of the RNA
transcribed from its provirus integrated into the host genome.
Reverse Transcriptase
An RNA-dependent DNA polymerase.
Satellite DNA
An array of tandemly repeated units spanning up to 10
6
bp and present mainly in
centromeric and paracentromeric heterochromatin. Satellite DNA usually forms a
prominent ‘‘satellite band’’ separable from the rest of genomic DNA by density
gradient centrifugation.
Short Interspersed Repeat (SINE) Element
A nonautonomous non-LTR retrotransposon derived mostly from host genes
containing a pol III internal promoter. SINE elements are retrotransposed by reverse
transcriptase encoded by LINE elements.
Superfamily of TEs
A group of related families of transposable elements.
Tandem Repeats
DNA units arranged in a head-to-tail manner.
Target-primed Reverse Transcription (TPRT)
A mechanism of integration of non-LTR retrotransposons into the genome.
Transposable Elements (TEs, Transposons, Mobile Elements)
DNA sequences that can move to different positions in the genome either by excision
and reinsertion, or by retrotransposition.
Transposase
An enzyme encoded by a DNA transposon and involved in its insertion and excision
from the host DNA.
Transposition
A relocation of a DNA sequence from one genomic site to another.
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