Project description:SPO11-promoted DNA double-strand breaks (DSBs) formation is a crucial step for meiotic recombination, and it is indispensable to detect the broken DNA ends accurately for dissecting the molecular mechanisms behind. Here, we report a novel technique, named DEtail-seq (DNA End tailing followed by sequencing), that can directly and quantitatively capture the meiotic DSB 3’ overhang hotspots at single-nucleotide resolution.
Project description:Methoxyacetic acid (MAA) is the active metabolite of the widely used industrial chemical ethylene glycol monomethyl ether, an established testicular toxicant. MAA induces the degradation of testicular germ cells in association with changes in gene expression in both germ cells and Sertoli cells of the testis. This study investigates the impact of MAA on gene expression in testicular Leydig cells, which play a critical role in germ cell survival and male reproductive function. Cultured mouse TM3 Leydig cells were treated with MAA for 3, 8, and 24 h and global gene expression was monitored by microarray analysis. A total of 3,912 MAA-responsive genes were identified. Ingenuity Pathway analysis identified reproductive system disease, inflammatory disease and connective tissue disorder as the top biological functions affected by MAA. The MAA-responsive genes were classified into 1,366 early responders, 1,387 mid-responders, and 1,138 late responders, based on the time required for MAA to elicit a response. Analysis of enriched functional clusters for each subgroup identified 106 MAA early response genes involved in transcription regulation, including 32 genes associated with developmental processes and 60 DNA-binding proteins that responded to MAA rapidly but transiently, and which may contribute to the downstream effects of MAA seen for large numbers of mid and late response genes. Genes within the phosphatidylinositol/phospholipase C/calcium signaling pathway, whose activity is required for potentiation of nuclear receptor signaling by MAA, were also enriched in the set of early MAA response genes. These findings on the progressive changes in gene expression induced by MAA in Leydig cells may help elucidate the signaling pathways perturbed by this testicular toxicant and explain its mechanism of toxicity at the gene level.
Project description:We collected whole genome testis expression data from hybrid zone mice. We integrated GWAS mapping of testis expression traits and low testis weight to gain insight into the genetic basis of hybrid male sterility.
Project description:PURPOSE: To provide a detailed gene expression profile of the normal postnatal mouse cornea. METHODS: Serial analysis of gene expression (SAGE) was performed on postnatal day (PN)9 and adult mouse (6 week) total corneas. The expression of selected genes was analyzed by in situ hybridization. RESULTS: A total of 64,272 PN9 and 62,206 adult tags were sequenced. Mouse corneal transcriptomes are composed of at least 19,544 and 18,509 unique mRNAs, respectively. One third of the unique tags were expressed at both stages, whereas a third was identified exclusively in PN9 or adult corneas. Three hundred thirty-four PN9 and 339 adult tags were enriched more than fivefold over other published nonocular libraries. Abundant transcripts were associated with metabolic functions, redox activities, and barrier integrity. Three members of the Ly-6/uPAR family whose functions are unknown in the cornea constitute more than 1% of the total mRNA. Aquaporin 5, epithelial membrane protein and glutathione-S-transferase (GST) omega-1, and GST alpha-4 mRNAs were preferentially expressed in distinct corneal epithelial layers, providing new markers for stratification. More than 200 tags were differentially expressed, of which 25 mediate transcription. CONCLUSIONS: In addition to providing a detailed profile of expressed genes in the PN9 and mature mouse cornea, the present SAGE data demonstrate dynamic changes in gene expression after eye opening and provide new probes for exploring corneal epithelial cell stratification, development, and function and for exploring the intricate relationship between programmed and environmentally induced gene expression in the cornea. Keywords: other
Project description:In mammals, piRNA populations are dynamic throughout male germ cell development. Embryonic piRNAs consist of both primary and secondary species and are mainly directed toward transposons. In meiotic cells, however, the piRNA population is transposon-poor and restricted to primary piRNAs derived from pachytene piRNA clusters. The mechanism controlling which piRNAs are present at each developmental stage is poorly understood. Here we show that RNF17 shapes adult meiotic piRNA content by suppressing the production of secondary piRNAs. In the absence of RNF17, ping-pong (secondary amplification) occurs inappropriately in meiotic cells – aberrantly targeting protein-coding genes and lncRNAs. Our data indicate that RNF17 comprises one component of a “refereeing” mechanism that prevents deleterious activity of the meiotic piRNA pathway by ensuring the selective loading of PIWI proteins with products of meiotic piRNA clusters.
Project description:In mammals, piRNA populations are dynamic throughout male germ cell development. Embryonic piRNAs consist of both primary and secondary species and are mainly directed toward transposons. In meiotic cells, however, the piRNA population is transposon-poor and restricted to primary piRNAs derived from pachytene piRNA clusters1-6. The mechanism controlling which piRNAs are present at each developmental stage is poorly understood. Here we show that RNF17 shapes adult meiotic piRNA content by suppressing the production of secondary piRNAs. In the absence of RNF17, ping-pong (secondary amplification) occurs inappropriately in meiotic cells – aberrantly targeting protein-coding genes and lncRNAs. Our data indicate that RNF17 comprises one component of a “refereeing” mechanism that prevents deleterious activity of the meiotic piRNA pathway by ensuring the selective loading of PIWI proteins with products of meiotic piRNA clusters.