Figure S7 Detection of pachytene and pre-pachytene piRNA precursor transcripts by semi-quantitative RT-PCR. In postnatal day 10 testes, the most advanced germ cells are leptotene/ zygotene spermatocytes. Pachytene spermatocytes appear first in day 14 testes. Mov10l1-deficient (ubiquitous knockout, Mov10l12/ 2) testes exhibit meiotic arrest at the zygotene stage and thus lack pachytene spermatocytes and spermatids [22]. In wild-type testes, the cluster 10 pre-pachytene piRNA precursor is abundantly expressed at day 10, while pachytene precursors are first detectable at day 14. Pachytene piRNA precursors are not detectable in Mov10l12/2 testes. Actb served as a loading control. (TIF) Table S1 Testis weight, sperm production, and fertility of wild type and Mov10l1fl/- Prm-Cre (mutant) male mice. (DOC) References 1. Siomi MC, Sato K, Pezic D, Aravin AA. (2011) PIWI-interacting small RNAs: The vanguard of genome defence. Nat Rev Mol Cell Biol 12: 246–258. 2. Pillai RS, Chuma S. 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Schonhoff SE, Giel-Moloney M, Leiter AB. (2004) Neurogenin 3-expressing progenitor cells in the gastrointestinal tract differentiate into both endocrine and non-endocrine cell types. Dev Biol 270: 443–454. PLOS Genetics | www.plosgenetics.org 11 November 2012 | Volume 8 | Issue 11 | e1003038