Submitted January 31, 2008
Returned for revision February 19, 2008
Accepted March 25, 2008
Testis
Mice Deficient for a Small Cluster of Piwi-Interacting RNAs Implicate Piwi-Interacting RNAs in Transposon Control
Mingang Xu ,
Yun You ,
Patricia Hunsicker ,
Tamaki Hori ,
Chris Small ,
Michael D Griswold ,
and
Norman B Hecht *
* To whom correspondence should be addressed. E-mail: nhecht{at}mail.med.upenn.edu.
Abstract
The mammalian testis expresses a class of small non-coding RNAs that interact with mammalian PIWI proteins. In mice, the PIWI-interacting RNAs (piRNAs) partner with mammalian PIWI proteins, PIWIL1 and PIWIL2, also known as MIWI and MILI, to maintain transposon silencing in the germline genome. Here we demonstrate that inactivation of Nct1/2, two non-coding RNAs encoding piRNAs, leads to de-repression of LINE-1 (L1), but does not affect mouse viability, spermatogenesis, testicular gene expression, or fertility. These findings indicate that piRNAs from a cluster on chromosome 2 are necessary to maintain transposon silencing.
Key words:
Male Reproductive Tract •
Testis •
Gametogenesis •
Gene regulation •
Spermatogenesis
