Final answer:
Transposition site-specific recombination (non-homologous) refers to the transposon-mediated movement of DNA sequences from one genomic location to a non-homologous site via enzymes like transposase, potentially resulting in changes to gene regulation.
Step-by-step explanation:
Transposition site-specific recombination (non-homologous) involves the movement of segments of DNA, known as transposons, from one location in the genome to another, non-homologous location. The process is carried out by the enzyme transposase, which facilitates recombination between inverted repeats. This results in the transposon being cut from its original location (donor site) and inserted into a new location in the genome.
The mechanisms of transposition include cut and paste transposition, where the transposon is completely excised and then transposed, and replicative transposition, which includes the production of a copy at the new insertion-site location. In the latter case, the formation of a cointegrate structure is involved, followed by its resolution either by site-specific or homologous recombination, leading to the loss of direct repeats at the original donor site.
A specialized case of transposition, known as retrotransposition, involves non-LTR retrotransposons like SINEs and LINEs, which can insert themselves into new genomic locations without the direct action of the transposase enzyme. Some forms of transposition can result in reciprocal translocations, exchanges between nonhomologous chromosomes that can affect gene regulation and are associated with conditions such as cancer and schizophrenia.