DNA transposons a fossil record in the genome

DNA transposons have only relatively recently been recognized in humans (Morgan 1995; Oosumi et al. 1995; Smit and Riggs 1996). They are thought to constitute 3% of the human genome (Lander et al. 2001). Active DNA transposon elements found in species such as Drosophila are characterized by encoding a transposase gene and having terminal inverted repeat sequences to which the transposase enzyme binds. Transposase catalyses transposition by cutting and pasting (van Luenen et al. 1994). The transposase excises the DNA transposon element and inserts it into a new genomic location after making

Human Transposase Binding Sequence

Gene

O DNA binding protein rt » Transposable element

Figure 8.3 Mobile DNA elements and wiring of a transcriptional network. Dispersal of a DNA binding site by multiple copies of a transposable element allows the potential for many genes to be simultaneously regulated (indicated by curved arrows) by binding of the same transcription factor to the DNA binding sites. Redrawn and reprinted by permission from Macmillan Publishers Ltd: Nature Reviews Genetics (Feschotte 2008), copyright 2008.

Gene

O DNA binding protein rt » Transposable element

Figure 8.3 Mobile DNA elements and wiring of a transcriptional network. Dispersal of a DNA binding site by multiple copies of a transposable element allows the potential for many genes to be simultaneously regulated (indicated by curved arrows) by binding of the same transcription factor to the DNA binding sites. Redrawn and reprinted by permission from Macmillan Publishers Ltd: Nature Reviews Genetics (Feschotte 2008), copyright 2008.

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