Subtraction by addition: domesticated transposases in programmed DNA elimination.
نویسندگان
چکیده
The ciliate Paramecium tetraurelia must eliminate approximately 60,000 short sequences from its genome to generate uninterrupted coding sequences in its somatic macronucleus. In this issue of Genes & Development, Baudry and colleagues (pp. 2478-2483) identify the protein that excises these noncoding sequences: a domesticated piggyBac transposase that has been adapted to remove what are likely the remnants of transposon insertions. This new study reveals how addition of a transposase to small RNA-directed silencing machinery can guide major genome reorganization.
منابع مشابه
The taming of the shrew
Transposons are mobile genetic elements that can be harmful for the host when mobilized. However, they are also genomic reservoirs for novel genes that can be evolutionarily beneficial. There are many examples of domesticated transposases, which play important roles in the hosts. In most cases domesticated transposases have lost their endonuclease activities and the hosts utilize their DNA-bind...
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عنوان ژورنال:
- Genes & development
دوره 23 21 شماره
صفحات -
تاریخ انتشار 2009