First Author | Nordstrand LM | Year | 2012 |
Journal | Nucleic Acids Res | Volume | 40 |
Issue | 21 | Pages | 10950-63 |
PubMed ID | 22965116 | Mgi Jnum | J:200274 |
Mgi Id | MGI:5507954 | Doi | 10.1093/nar/gks839 |
Citation | Nordstrand LM, et al. (2012) Alkbh1 and Tzfp repress a non-repeat piRNA cluster in pachytene spermatocytes. Nucleic Acids Res 40(21):10950-63 |
abstractText | Piwi proteins and Piwi-interacting small RNAs (piRNAs) have known functions in transposon silencing in the male germline of fetal and newborn mice. Both are also present in adult testes; however, their function here remains a mystery. Here, we confirm that most piRNAs in meiotic spermatocytes originate from clusters in non-repeat intergenic regions of DNA. The regulation of these piRNA clusters, including the processing of the precursor transcripts into individual piRNAs, is accomplished through mostly unknown processes. We present a possible regulatory mechanism for one such cluster, named cluster 1082B, located on chromosome 7 in the mouse genome. The 1082B precursor transcript and its 788 unique piRNAs are repressed by the Alkbh1 dioxygenase and the testis-specific transcription repressor Tzfp. We observe a remarkable >1000-fold upregulation of individual piRNAs in pachytene spermatocytes isolated from Alkbh1- and Tzfp-deficient murine testes. Repression of cluster 1082B is further supported by the identification of a 10-bp Tzfp recognition sequence contained within the precursor transcript. Downregulation of LINE1 and IAP transcripts in the Alkbh1- and Tzfp-deficient mice leads us to propose a potential role for the 1082B-encoded piRNAs in transposon control. |