RT Journal
A1 Yamamoto, Yasuhiro
A1 Watanabe, Toshiaki
A1 Hoki, Yuko
A1 Shirane, Kenjiro
A1 Li, Yufeng
A1 Ichiiyanagi, Kenji
A1 Kuramochi-Miyagawa, Satomi
A1 Toyoda, Atsushi
A1 Fujiyama, Asao
A1 Oginuma, Masayuki
A1 Suzuki, Hitomi
A1 Sado, Takashi
A1 Nakano, Toru
A1 Sasaki, Hiroyuki
T1 Targeted gene silencing in mouse germ cells by insertion of a homologous DNA into a piRNA generating locus
JF Genome Research 
JO Genome Research 
YR 2013 
FD February 01 
VO 23 
IS 2 
SP 292 
OP 299 
DO 10.1101/gr.137224.112 
UL http://genome.cshlp.org/content/23/2/292.abstract 
AB In germ cells, early embryos, and stem cells of animals, PIWI-interacting RNAs (piRNAs) have an important role in silencing retrotransposons, which are vicious genomic parasites, through transcriptional and post-transcriptional mechanisms. To examine whether the piRNA pathway can be used to silence genes of interest in germ cells, we have generated knock-in mice in which a foreign DNA fragment was inserted into a region generating pachytene piRNAs. The knock-in sequence was transcribed, and the resulting RNA was processed to yield piRNAs in postnatal testes. When reporter genes possessing a sequence complementary to portions of the knock-in sequence were introduced, they were greatly repressed after the time of pachytene piRNA generation. This repression mainly occurred at the post-transcriptional level, as degradation of the reporter RNAs was accelerated. Our results show that the piRNA pathway can be used as a tool for sequence-specific gene silencing in germ cells and support the idea that the piRNA generating regions serve as traps for retrotransposons, enabling the host cell to generate piRNAs against active retrotransposons.