Disruption of the MSL complex inhibits tumor maintenance by exacerbating chromosomal instability
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE144019 | GEO | 2021/01/31
REPOSITORIES: GEO
Similar Datasets
Project description:Disruption of the MSL complex inhibits tumor maintenance by exacerbating chromosomal instability
| PRJNA602514 | ENA
Project description:Rewiring of cellular programmes in malignant cells generates cancer-specific vulnerabilities. Here, using an unbiased screening strategy aimed at identifying non-essential genes required by tumour cells to sustain unlimited proliferative capacity, we identify the male-specific lethal (MSL) acetyltransferase complex as a vulnerability of genetically unstable cancers. We find that disruption of the MSL complex and consequent loss of the associated H4K16ac mark do not substantially alter transcriptional programmes but compromise chromosome integrity and promote chromosomal instability (CIN) that progressively exhausts the proliferative potential of cancer cells through a p53-independent mechanism. This effect is dependent on pre-existing genomic instability, and normal cells are insensitive to MSL disruption. Using cell- and patient-derived xenografts from multiple cancer types, we show that excessive CIN induced by MSL disruption inhibits tumour maintenance. Our findings suggest that targeting MSL may be a valuable means to increase CIN beyond the level tolerated by cancer cells without inducing severe adverse effects in normal tissues.
| S-EPMC7610593 | biostudies-literature
Project description:Long non-coding RNAs are involved in dosage compensation both in mammals and in Drosophila by inducing changes in the X-chromosome chromatin structure. In Drosophila melanogaster, roX1 and roX2 are long non-coding RNAs that together with proteins form the male-specific lethal (MSL) complex, which coats the entire male X-chromosome and mediates dosage compensation by increased transcriptional output. It has been shown that in polytene chromosomes, in absence of both roX1 and roX2, the MSL-complex is decreased on the male X-chromosome and found relocated to the chromocenter, and the 4th chromosome. Here we address the role of roX RNAs in MSL-complex targeting and in the evolution of dosage compensation in Drosophila. We performed ChIP-seq experiments and show that MSL-complex recruitment to high affinity sites (HAS) on the X-chromosome is independent on roX and that the HAS sequence motif is conserved in D. simulans. Additionally, a complete and enzymatically active MSL-complex is recruited to six specific genes on the 4th chromosome. Interestingly, our sequence analysis shows that in the absence of roX RNAs, the MSL-complex has affinity to regions enriched in Hoppel transposable elements and to repeats in general. We hypothesize that roX mutants reveal an ancient targeting of the MSL-complex and propose that the role of roX RNAs is to restrict MSL-complex from binding to heterochromatin.
2014-11-07 | GSE58768 | GEO
Project description:X-chromosome dosage compensation in Drosophila requires the male-specific lethal (MSL) complex, which up-regulates gene expression from the single male X chromosome. Here, we define X-chromosome-specific MSL binding at high resolution in two male cell lines and in late-stage embryos. We find that the MSL complex is highly enriched over most expressed genes, with binding biased toward the 3' end of transcription units. The binding patterns are largely similar in the distinct cell types, with ~600 genes clearly bound in all three cases. Genes identified as clearly bound in one cell type and not in another indicate that attraction of MSL complex correlates with expression state. Thus, sequence alone is not sufficient to explain MSL targeting. We propose that the MSL complex recognizes most X-linked genes, but only in the context of chromatin factors or modifications indicative of active transcription. Distinguishing expressed genes from the bulk of the genome is likely to be an important function common to many chromatin organizing and modifying activities. Keywords: ChIP-chip
2007-08-01 | GSE8575 | GEO
Project description:Drosophila MSL complex binds the single male X chromosome to upregulate gene expression to equal that from the two female X chromosomes. However, it has been puzzling that ~25% of transcribed genes on the X do not stably recruit MSL complex. Here, we find that almost all active genes on the X are associated with robust H4 Lys16 acetylation (H4K16ac), the histone modification catalyzed by MSL complex. The distribution of H4K16ac is much broader than that of MSL complex, and our results favor the idea that chromosome-wide H4K16ac reflects transient association of MSL complex, occurring through spreading or chromosomal looping. Our results parallel those of localized Polycomb repressive complex and its more broadly distributed H3K27me3 chromatin mark, suggesting a common principle for the establishment of active and silenced chromatin domains
2009-06-10 | GSE14884 | GEO
Project description:In Drosophila, X chromosome dosage compensation requires the male-specific lethal (MSL) complex, which associates with actively transcribed genes on the single male X chromosome to upregulate transcription approximately 2-fold. We found that on the male X chromosome, or when MSL complex is ectopically localized to an autosome, histone H3K36 trimethylation (H3K36me3) is a strong predictor of MSL binding. We isolated mutants lacking Set2, the H3K36me3 methyltransferase, and found that Set2 is an essential gene in both sexes of Drosophila. In set2 mutant males, MSL complex maintains X specificity but exhibits reduced binding to target genes. Furthermore, recombinant MSL3 protein preferentially binds nucleosomes marked by H3K36me3 in vitro. Our results support a model in which MSL complex uses high-affinity sites to initially recognize the X chromosome and then associates with many of its targets through sequence-independent features of transcribed genes. Keywords: ChIP-chip ChIP-chip experiments were performed on custom Nimblegen arrays (GPL5636). Each array contained 388,000 oligonucleotide probes covering all of the X and the 2L chromosomes, with a 100 bp resolution (50mer probes with 50 bp gaps). The design was based on FlyBase 3.2. For the superspreading experiments, an additional array was used that contains the entire X chromosome and 3R (GPL5660). MSL complex binding sites on both arrays are the same and signal on the 3R chromosome was at background level.
2007-09-20 | E-GEOD-8557 | biostudies-arrayexpress
Project description:In Drosophila, X chromosome dosage compensation requires the male-specific lethal (MSL) complex, which associates with actively transcribed genes on the single male X chromosome to upregulate transcription approximately 2-fold. We found that on the male X chromosome, or when MSL complex is ectopically localized to an autosome, histone H3K36 trimethylation (H3K36me3) is a strong predictor of MSL binding. We isolated mutants lacking Set2, the H3K36me3 methyltransferase, and found that Set2 is an essential gene in both sexes of Drosophila. In set2 mutant males, MSL complex maintains X specificity but exhibits reduced binding to target genes. Furthermore, recombinant MSL3 protein preferentially binds nucleosomes marked by H3K36me3 in vitro. Our results support a model in which MSL complex uses high-affinity sites to initially recognize the X chromosome and then associates with many of its targets through sequence-independent features of transcribed genes. Keywords: ChIP-chip
2007-09-20 | GSE8557 | GEO
Project description:Drosophila MSL complex binds the single male X chromosome to upregulate gene expression to equal that from the two female X chromosomes. However, it has been puzzling that ~25% of transcribed genes on the X do not stably recruit MSL complex. Here, we find that almost all active genes on the X are associated with robust H4 Lys16 acetylation (H4K16ac), the histone modification catalyzed by MSL complex. The distribution of H4K16ac is much broader than that of MSL complex, and our results favor the idea that chromosome-wide H4K16ac reflects transient association of MSL complex, occurring through spreading or chromosomal looping. Our results parallel those of localized Polycomb repressive complex and its more broadly distributed H3K27me3 chromatin mark, suggesting a common principle for the establishment of active and silenced chromatin domains For ChIP-on-chip experiments in larvae, 1000 third instar larvae were collected and chromatin was prepared as described previously. Five IPs were performed for each of the two biological replicates. For SL2 cells and male larvae, one ChIP-on-chip experiment was performed using anti-H4K16ac from Serotec (AHP417) (1-2 ul/IP). However, this antibody was discontinued, and an additional experiment for each was performed using anti-H4K16ac from Upstate/Millipore (07-329) (3 ul/IP). Both replicates for Kc cells and female larvae were also performed using anti-H4K16ac from Upstate/Millipore. Replicate experiments were highly reproducible.
2009-06-10 | E-GEOD-14884 | biostudies-arrayexpress
Project description:In Drosophila, the global increase in transcription from the X chromosome in males to compensate for its monosomy is mediated by the male-specific-lethal complex (MSL-C) consisting of five proteins and two non-coding RNAs, roX1 and roX2. After an initial sequence dependent recognition by the MSL-C of 150-300 high affinity sites, the spreading to the majority of the X-linked genes depends on local MSL-C concentration and active transcription. Here we ask whether any additional RNA species are associated to the MSL-C. No additional roX were found but a strong association was found between the msl2 mRNA and the MSL-C. Based on our results we propose a model in which a non-chromatin associated partial or complete MSL-C titrates newly transcribed msl2 mRNA and thus feed-back regulates the amount of available MSL-C.
2011-04-13 | GSE20249 | GEO
Project description:In Drosophila, the global increase in transcription from the X chromosome in males to compensate for its monosomy is mediated by the male-specific-lethal complex (MSL-C) consisting of five proteins and two non-coding RNAs, roX1 and roX2. After an initial sequence dependent recognition by the MSL-C of 150-300 high affinity sites, the spreading to the majority of the X-linked genes depends on local MSL-C concentration and active transcription. Here we ask whether any additional RNA species are associated to the MSL-C. No additional roX were found but a strong association was found between the msl2 mRNA and the MSL-C. Based on our results we propose a model in which a non-chromatin associated partial or complete MSL-C titrates newly transcribed msl2 mRNA and thus feed-back regulates the amount of available MSL-C. In total 12 samples; 4 Input files (4 different conditions) with the corresponding 8 RIP samples (2 different antibodies, same 4 conditions as Input)
2011-04-13 | E-GEOD-20249 | biostudies-arrayexpress