A composite transposon is similar in function to
simple transposons and
insertion sequence (IS) elements in that it has protein coding
DNA segments flanked by inverted, repeated sequences that can be recognized by transposase enzymes. A composite
transposon
A transposable element (TE, transposon, or jumping gene) is a nucleic acid sequence in DNA that can change its position within a genome, sometimes creating or reversing mutations and altering the cell's genetic identity and genome size. Transp ...
, however, is flanked by two separate IS elements which may or may not be exact replicas. Instead of each IS element moving separately, the entire length of DNA spanning from one IS element to the other is transposed as one complete unit. Composite transposons will also often carry one or more genes conferring
antibiotic resistance
Antimicrobial resistance (AMR) occurs when microbes evolve mechanisms that protect them from the effects of antimicrobials. All classes of microbes can evolve resistance. Fungi evolve antifungal resistance. Viruses evolve antiviral resistanc ...
.
Flanked by SINEs in mammalian genomes
Two SINEs may act in concert to flank and mobilize an intervening single copy DNA sequence. This was reported for a 710 bp DNA sequence upstream of the bovine beta globin gene.
The DNA arrangement forms a composite transposon whose presence has been confirmed by the complete
bovine genomic sequence where the mobilized sequence may be found on bovine chromosome 15 in conti
NW_001493315.1nucleotides #1085432–1086142 and the originating sequence may be found on bovine chromosome 2 in conti
NW_001501789.2nucleotides #1096679–1097389. It is likely that similar composite transposons exist in other bovine genomic regions and other mammalian genomes. They could be detected with suitable algorithms.
See also
*
Tn10
References
Mobile genetic elements
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