Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Piwi proteins and piRNAs in mammalian oocytes and early embryos

ABSTRACT: Germ cells of most animals critically depend on piRNAs and Piwi proteins. Surprisingly, piRNAs in mouse oocytes are relatively rare and dispensable. We present compelling evidence for strong Piwi-piRNA expression in oocytes of other mammals. Human fetal oocytes express PIWIL2 and transposon-enriched piRNAs. Oocytes in adult human ovary express PIWIL1 and PIWIL2, while those in bovine ovary just express PIWIL1. In human, macaque and bovine ovaries we find piRNAs that resemble testis-borne pachytene piRNAs. Isolated bovine follicular oocytes were shown to contain abundant, relatively short piRNAs that preferentially target transposable elements. Using label-free quantitative proteome analysis we show that these maturing oocytes strongly and specifically express the thus-far uncharacterized PIWIL3 protein, alongside other known piRNA-pathway components. In bovine early embryos these piRNAs are still abundant, revealing a potential impact of piRNAs on mammalian embryogenesis. Our results reveal unexpected, highly dynamic piRNA pathways in mammalian oocytes and early embryos. Analyses of multiple small RNA libraries obtained from fetal/adult oocytes, cumulus cells, ovary, testis and 2-4 cell stage ivf embryos of multiple mammalian species.

ORGANISM(S): Macaca fascicularis

SUBMITTER: David Rosenkranz

PROVIDER: E-GEOD-64942 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Publications

Piwi proteins and piRNAs in mammalian oocytes and early embryos.

Roovers Elke F EF Rosenkranz David D Mahdipour Mahdi M Han Chung-Ting CT He Nannan N Chuva de Sousa Lopes Susana M SM van der Westerlaken Lucette A J LA Zischler Hans H Butter Falk F Roelen Bernard A J BA Ketting René F RF

Cell reports 20150326 12

Germ cells of most animals critically depend on piRNAs and Piwi proteins. Surprisingly, piRNAs in mouse oocytes are relatively rare and dispensable. We present compelling evidence for strong Piwi and piRNA expression in oocytes of other mammals. Human fetal oocytes express PIWIL2 and transposon-enriched piRNAs. Oocytes in adult human ovary express PIWIL1 and PIWIL2, whereas those in bovine ovary only express PIWIL1. In human, macaque, and bovine ovaries, we find piRNAs that resemble testis-borne ...[more]

PMID: 25818294

Similar Datasets

Project description:Purpose:To evaluate the effect of transient Global Cerebral Ischemia(tGCI) with Hypoxic Postconditioning (HPC) on piRNA expression profiles, piRNAs sequencing was performed. Methods: Total RNA of each sample (n=3 in each group) was prepared using Trizol reagent (Invitrogen), and the RNA quality and integrity were confirmed. 5’- and 3’-Adaptors were ligated to the obtained small RNA. Reverse transcription followed by PCR was used to create cDNA constructs. Subsequently, an about 150 bp fraction corresponding to approximate the adaptor-ligated constructs derived from the 30 nts piRNA fragment was excised and purified. The purified libraries were sequenced on Illumina HiSeq 2000 apparatus. The raw data were refined using cutadapt software (v1.9.1). After filtering out low quality reads and short reads (<15 nts), trimmed reads from all samples were pooled, and piano software was used to predict novel piRNAs. The trimmed reads were aligned to the merged rat piRNA databases (known piRNA from piRNABank plus the newly predicted piRNAs) using Novoalign software (v3.02.12) with at most one mismatch. PiRNA-binding transposon and targets were predicted by miranda software (v3.3a). piRNA-targets networks were plotted by cytoscape software (v2.8.0). Results: After tGCI, a total of 5574 piRNAs in CA1 was detected after 26 h of reperfusion. Of those, 12 were significantly upregulated compared with Sham rats (≥1.5-fold change, p<0.05), including 6 novel piRNAs. Of the 12 piRNAs, 4 showed ≥2-fold change. In comparison to tGCI group, 6 piRNAs in CA1 were significantly downregulated after HPC. Interestingly, the piRNAs rno_piR_000618, rno_piR_017990 and rno_piR_014971 were significantly changed in both tGCI and HPC groups Conclusions: In our study, we identified a cohort of piRNAs in CA1 of rats. Furthermore, we demonstrated directly contrast changes of piRNAs interacted with Piwil2 in CA1 after tGCI, as compared to those in HPC rats. Therefore, this study revealed that PIWI/piRNAs respond to ischemic brain damage and neuroprotection mediated by HPC. To the best of our knowledge, this is the first study ever on piRNAs associated with Piwil2 in cerebral ischemic tolerance.

Project description:Background: The piRNA pathway has been shown in model organisms to be involved in silencing of transposons thereby providing genome stability. In D. melanogaster the majority of piRNAs map to these sequences. The medically important mosquito species Aedes aegypti has a large genome size, a high transposon load which includes Miniature Inverted repeat Transposable Elements (MITES) and an expansion of the piRNA biogenesis genes. Studies of transgenic lines of Ae. aegypti have indicated that introduced transposons are poorly remobilized and we sought to explore the basis of this. We wished to analyze the piRNA profile of Ae. aegypti and thereby determine if it be responsible for transposon silencing in this mosquito. Results: Estimated piRNA sequence diversity was comparable between Ae. aegypti and D. melanogaster, but surprisingly only 19% of mosquito piRNAs mapped to transposons compared to 51% for D. melanogaster. Ae. aegypti piRNA clusters made up a larger percentage of the total genome than those of D. melanogaster but did not contain significantly higher percentages of transposon derived sequences than other regions of the genome. Ae. aegypti contains a number of protein coding genes that may be sources of piRNA biogenesis with two, traffic jam and maelstrom, implicated in this process in model organisms. Several genes of viral origin were also targeted by piRNAs. Examination of six mosquito libraries that had previously been transformed with transposon derived sequence revealed that new piRNA sequences had been generated to the transformed sequences, suggesting that they may have stimulated a transposon inactivation mechanism. Conclusions: Ae. aegypti has a large piRNA complement that maps to transposons but primarily gene sequences, including many viral-derived sequences. This, together the more uniform distribution of piRNA clusters throughout its genome suggest that some aspects of the piRNA system differ between Ae. aegypti and D. melanogaster. 5 small RNA libraries were generated from total RNA of whole adult Aedes aegypti tissues, two of these libraries were sequenced twice (technical replicates). 1 small RNA library was generated from total RNA of a whole adult Drosophila melanogaster tissue.

Dataset Information

Piwi proteins and piRNAs in mammalian oocytes and early embryos

Publications

Piwi proteins and piRNAs in mammalian oocytes and early embryos.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets