Illumina deep sequencing data were validated by quantitative PCR (qPCR) analysis using piRNA-specific LNA primers (Exiqon) as previously described (16 (link)). In brief, using NCode™VILO™miRNA cDNA Synthesis Kit (Invitrogen) enabling poly(A) tailing of the small RNAs according to the manufacturer’s instructions with a universal RT primer, the purified small RNA was converted to cDNA. Subsequently, the resulting cDNA was used as a template for qPCR analyses using NCode™EXPRESS®SYBR GreenER™miRNA qRT-PCR Kit (Invitrogen) on the ABI 7900 Real-time PCR system by the Nemours Biomolecular Core using standard workflows and operating procedures. The final results of qPCR in relative level of piRNA-like sncRNAs normalized to that of U6 were expressed as the ratio of the injured levels to the uninjured level. To verify piRNA-specific primer specificity, we confirmed a single peak in the melting-curve analysis, as well as run the reaction products on a 5% agarose gel (NuSieve 3: 1; Lonza) for all genes analyzed.