Project description:The Caenorhabditis elegans somatic gonad was the first organ to have its cell lineage determined, and the gonadal lineages of the two sexes differ greatly in their pattern of cell divisions, cell migration and cell types. Despite much study, the genetic pathways that direct early gonadal development and establish its sexual dimorphism remain largely unknown, with just a handful of regulatory genes identified from genetic screens. To help define the genetic networks that regulate gonadal development, we employed cell-specific RNA-seq. We identified transcripts present in Z1/Z4 or Z1/Z4 daughter cells in each sex at the onset of somatic gonadal sexual differentiation. For comparison, transcripts were identified in whole animals at both time points. Pairwise comparisons of samples identified several hundred gonad-enriched transcripts, including most known Z1/Z4-enriched mRNAs, and reporter analysis confirmed the effectiveness of this approach. Prior to the Z1/Z4 division few sex-biased Z1/Z4 transcripts were detectable, but less than six hours later, we identified more than 250 sex-biased transcripts in the Z1/Z4 daughters, of which about a third were enriched in the somatic gonad cells compared to cells from whole animals. This indicates that a robust sex-biased developmental program, some of it gonad-specific, initiates in these cells around the time of the first Z1/Z4 division. Cell-specific analysis also identified approximately 70 previously unannotated mRNA isoforms that are enriched in Z1/Z4 or their daughters. Our data suggest that early sex differentiation in the gonad is controlled by a relatively small suite of differentially expressed genes, even after dimorphism has become apparent. 20 total sample: two time points, two sexes, and gonadal cells or whole animals. The earlier time point was collected in triplicate and was harvested 9.5 hours after starved, hatched L1s were fed. The later time point was collected in duplicate and was harvested 15 hour after starved, hatched L1 were fed. Replicates of either dissociated whole animals or gonadal cells (Z1/Z4 or Z1/Z4 daughter) from both male and hermaphrodites were harvested for each time point.
Project description:The Caenorhabditis elegans somatic gonad was the first organ to have its cell lineage determined, and the gonadal lineages of the two sexes differ greatly in their pattern of cell divisions, cell migration and cell types. Despite much study, the genetic pathways that direct early gonadal development and establish its sexual dimorphism remain largely unknown, with just a handful of regulatory genes identified from genetic screens. To help define the genetic networks that regulate gonadal development, we employed cell-specific RNA-seq. We identified transcripts present in Z1/Z4 or Z1/Z4 daughter cells in each sex at the onset of somatic gonadal sexual differentiation. For comparison, transcripts were identified in whole animals at both time points. Pairwise comparisons of samples identified several hundred gonad-enriched transcripts, including most known Z1/Z4-enriched mRNAs, and reporter analysis confirmed the effectiveness of this approach. Prior to the Z1/Z4 division few sex-biased Z1/Z4 transcripts were detectable, but less than six hours later, we identified more than 250 sex-biased transcripts in the Z1/Z4 daughters, of which about a third were enriched in the somatic gonad cells compared to cells from whole animals. This indicates that a robust sex-biased developmental program, some of it gonad-specific, initiates in these cells around the time of the first Z1/Z4 division. Cell-specific analysis also identified approximately 70 previously unannotated mRNA isoforms that are enriched in Z1/Z4 or their daughters. Our data suggest that early sex differentiation in the gonad is controlled by a relatively small suite of differentially expressed genes, even after dimorphism has become apparent.
Project description:The Drosophila ubiquitin receptor dDsk2 associates to chromatin and stabilizes binding of the euchromatic dHP1c/WOC/ROW-complex (dHP1EU) to the transcription-start site (TSS) of active genes ChIP-Seq peak calling of WOC, ROW, Z4, HP1c and Dsk2 against Input sample in Drosophila melanogaster S2 cells
Project description:Two novel aspochalasins, tricochalasin A (1) and aspochalasin A2 (2), along with three known compounds (3?5) have been isolated from the different culture broth of Aspergillus sp., which was found in the gut of a marine isopod Ligia oceanica. Compound 1 contains a rare 5/6/6 tricyclic ring fused with the aspochalasin skeleton. The structures were determined on the basis of electrospray ionisation mass spectroscopy (ESIMS), nuclear magnetic resonance (NMR) spectral data, and the absolute configurations were further confirmed by modified Mosher's method. Cytotoxicity against the prostate cancer PC3 cell line were assayed by the MTT method. Compound 3 showed strong activity while the remaining compounds showed weak activity.
Project description:Nuclear protein in testis (NUT) carcinoma (NC) is a rare, distinctly aggressive subtype of squamous carcinoma defined by the presence of NUT-fusion oncogenes resulting from chromosomal translocation. In most cases, the NUT gene (NUTM1) is fused to bromodomain containing 4 (BRD4) forming the BRD4-NUT oncogene. Here, a novel fusion partner to NUT was discovered using next-generation sequencing and FISH from a young patient with an undifferentiated malignant round cell tumor. Interestingly, the NUT fusion identified involved ZNF592, a zinc finger containing protein, which was previously identified as a component of the BRD4-NUT complex. In BRD4-NUT-expressing NC cells, wild-type ZNF592 and other associated "Z4" complex proteins, including ZNF532 and ZMYND8, colocalize with BRD4-NUT in characteristic nuclear foci. Furthermore, ectopic expression of BRD4-NUT in a non-NC cell line induces sequestration of Z4 factors to BRD4-NUT foci. Finally, the data demonstrate the specific dependency of NC cells on Z4 modules, ZNF532 and ZNF592. IMPLICATIONS: This study establishes the oncogenic role of Z4 factors in NC, offering potential new targeted therapeutic strategies in this incurable cancer.Visual Overview: http://mcr.aacrjournals.org/content/molcanres/16/12/1826/F1.large.jpg.
Project description:Drosophila telomere maintenance depends on the transposition of the specialized retrotransposons HeT-A, TART, and TAHRE. Controlling the activation and silencing of these elements is crucial for a precise telomere function without compromising genomic integrity. Here we describe two chromosomal proteins, JIL-1 and Z4 (also known as Putzig), which are necessary for establishing a fine-tuned regulation of the transcription of the major component of Drosophila telomeres, the HeT-A retrotransposon, thus guaranteeing genome stability. We found that mutant alleles of JIL-1 have decreased HeT-A transcription, putting forward this kinase as the first positive regulator of telomere transcription in Drosophila described to date. We describe how the decrease in HeT-A transcription in JIL-1 alleles correlates with an increase in silencing chromatin marks such as H3K9me3 and HP1a at the HeT-A promoter. Moreover, we have detected that Z4 mutant alleles show moderate telomere instability, suggesting an important role of the JIL-1-Z4 complex in establishing and maintaining an appropriate chromatin environment at Drosophila telomeres. Interestingly, we have detected a biochemical interaction between Z4 and the HeT-A Gag protein, which could explain how the Z4-JIL-1 complex is targeted to the telomeres. Accordingly, we demonstrate that a phenotype of telomere instability similar to that observed for Z4 mutant alleles is found when the gene that encodes the HeT-A Gag protein is knocked down. We propose a model to explain the observed transcriptional and stability changes in relation to other heterochromatin components characteristic of Drosophila telomeres, such as HP1a.