Sequence variation within similar cis-elements promotes context-specific functions of two Drosophila GA-binding transcription factors (ChIP-seq data set)
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ABSTRACT:
ORGANISM(S): Drosophila melanogaster
PROVIDER: GSE107059 | GEO | 2018/02/01
REPOSITORIES: GEO
Similar Datasets
Project description:The Drosophila male-specific lethal (MSL) complex binds to the male X chromosome to activate transcription, and consists of five proteins, MSL1, MSL2, MSL3, MOF, MLE, and two roX RNAs. The MLE helicase remodels the roX lncRNAs, enabling the lncRNA-mediated assembly of the Drosophila dosage compensation complex. MSL2 is expressed only in males and interacts with the N-terminal zinc-finger of the transcription factor CLAMP that is important for specific recruitment of the MSL complex on the male X chromosome. Here we found that the unstructured C-terminal region of MLE interacts with 6-7 zinc-finger domains of CLAMP. In vitro 4-5 zinc fingers are critical for specific DNA-binding of CLAMP with GA-repeats, which constitute the core motif at the high affinity binding sites for MSL proteins. Deletion of the Clamp Binding Domain (CBD) in MLE results in decreasing of MSL proteins association with male X chromosome and increasing of male lethality. These results suggest that interactions of unstructured regions in MSL2 and MLE with CLAMP zinc finger domains are important for the specific recruitment of the MSL complex on the male X chromosome.
2024-03-20 | GSE239354 | GEO
Project description:The essential process of dosage compensation is required to equalize gene expression of X-chromosome genes between males (XY) and females (XX). In Drosophila, the conserved Male-specific lethal (MSL) histone acetyltransferase complex mediates dosage compensation by increasing transcript levels from genes on the single male X-chromosome approximately two-fold. Consistent with its increased levels of transcription, the male X-chromosome has enhanced chromatin accessibility, distinguishing it from the autosomes. Here, we demonstrate that the non-sex specific CLAMP (Chromatin-linked adaptor for MSL proteins) zinc finger protein that recognizes GA-rich sequences genome-wide promotes the specialized chromatin environment on the male X-chromosome. In contrast, MSL complex is not required for global male X-chromosome chromatin accessibility, and instead promotes chromatin accessibility just at its highest-occupancy sites. Overall, our results support a model where synergy between the global increases in accessibility promoted by CLAMP and the local effects of MSL complex create a specialized chromatin domain on the male X-chromosome.
2017-10-31 | GSE99893 | GEO
Project description:The essential process of dosage compensation is required to equalize gene expression of X-chromosome genes between males (XY) and females (XX). In Drosophila, the conserved Male-specific lethal (MSL) histone acetyltransferase complex mediates dosage compensation by increasing transcript levels from genes on the single male X-chromosome approximately two-fold. Consistent with its increased levels of transcription, the male X-chromosome has enhanced chromatin accessibility, distinguishing it from the autosomes. Here, we demonstrate that the non-sex specific CLAMP (Chromatin-linked adaptor for MSL proteins) zinc finger protein that recognizes GA-rich sequences genome-wide promotes the specialized chromatin environment on the male X-chromosome. In contrast, MSL complex is not required for global male X-chromosome chromatin accessibility, and instead promotes chromatin accessibility just at its highest-occupancy sites. Overall, our results support a model where synergy between the global increases in accessibility promoted by CLAMP and the local effects of MSL complex create a specialized chromatin domain on the male X-chromosome.
2017-10-31 | GSE99842 | GEO
Project description:Transcription regulators select their genomic binding sites from a large pool of similar, non‑functional sequences. Although general principles that allow such discrimination are known, the complexity of DNA elements often precludes a prediction of functional sites. The process of dosage compensation in Drosophila allows exploring the rules underlying binding site selectivity. The male-specific-lethal (MSL) Dosage Compensation Complex selectively binds to some 300 X-chromosomal ‘High Affinity Sites’ (HAS) containing GA‑rich ‘MSL recognition elements’ (MREs), but disregards thousands of other MRE sequences in the genome. The DNA‑binding subunit MSL2 alone identifies a subset of MREs, but fails to recognize most MREs within HAS. The ‘Chromatin-linked adaptor for MSL proteins’ (CLAMP) also interacts with many MREs genome‑wide and promotes DCC binding to HAS. Using genome‑wide DNA‑immunoprecipitation we describe extensive cooperativity between both factors, depending on the nature of the binding sites. These are explained by physical interaction between MSL2 and CLAMP. In vivo, both factors cooperate to compete with nucleosome formation at HAS. The male‑specific MSL2 thus synergises with a ubiquitous GA‑repeat binding protein for refined X/autosome discrimination.
2018-12-05 | GSE119708 | GEO
Project description:CLAMP is a maternally deposited transcription factor binding to GA-rich genomic region. It recruits male-specific MSL (Male sex-lethal) complex on male X-chromosome that regulates dosage compensation in males, and competes with other GA-binding proteins like GAF, acting both synergistically as well as antagonistically in a context dependent manner. Considering CLAMP's male specific role in dosage compensation but ubiquitous expression in both males and females, what regulates differential binding of CLAMP is still unknown. Furthermore, ChiP-seq analysis has being long used to study protein-DNA interactions, however, since it uses physical force to shear DNA after protein capture, it is prone to both false negative and false positive peaks being called. To minimise these discrepancies, a recent CutnRun MNase based technique have being developed (Heinkoff Lab) which captures the DNA fragments bound to protein of interest. Due to higher accuracy in identifying the size and sequence of the protein bound DNA region, one can also identify monomeric or multimeric protein binding on the chromatin. We have used this technique to identify differential and shared CLAMP binding sites in male and female cells. We also compared CLAMP DNA binding peaks with CLAMP RNA binding peaks (iCLIP data) in male and female cells to understand sex-biased co-transcriptional RNA processing mechanism.
2023-12-31 | GSE220053 | GEO
Project description:Dosage compensation in D. melanogaster males is achieved via targeting of the MSL complex to X chromosomal genes. This is proposed to involve initial sequence-specific recognition of the X at ~150-300 chromatin entry sites, and subsequent spreading to nearby active genes. Here we test a model in which the spreading step requires transcription and is sequence-independent. We ask whether, in the native context of the X chromosome, MSL complex will target genes of autosomal origin. We find that MSL complex does bind such genes, but only if transcriptionally active. Targeting is accompanied by acetylation of the histone H4K16 residue and two-fold transcriptional up-regulation. We conclude that the presence of a long-sought specific DNA sequence within X-linked genes is not obligatory for MSL complex binding. Instead, physical linkage and transcription play the pivotal roles in the identification of MSL targets irrespective of their origin and DNA sequence. Keywords: Epigenetics ChIP-seq measurements of MSL complex binding and input control. Chromatin was prepared from third instar male larvae of a genotype y w TrojanElephant; MSL3-TAP; msl3. TrojanElephant is a mini-white- and yellow-marked transposition of genomic region spanning 65 kb from cg13773 to snRNP70K. MSL3-TAP is a mini-white-marked TAP-tagged genomic msl3 transgene. IgG beads were used for pull-down.
2009-08-20 | E-GEOD-17729 | biostudies-arrayexpress
Project description:CLAMP transcription factor is a GA binding protein that recruits the male dosage compensation complex MSL to male X-chromosome, thus upregulating transcription level twice that of female X-chromosomes. Interestingly, CLAMP is essential for survival of both male and female individuals. However, what function it plays at the autosomes, especially in females is not known. It is well establised that GA-rich sequences to which CLAMP bind have evolved from polypyrimidine tracts that regulate splicing. Also, MALDI-MS data shows that CLAMP binds to RNA binding proteins involved in sex-specific splicing like, Squid. Furthermore, as part of MSL complex CLAMP interacts with MLE, a RNA helicase which is a known component of spliceosome complex conserved from flies to humans. Thus, we hypothesized that CLAMP plays a role in sex-spcific splicing. Given that CLAMP is a transcription factor, understanding mechanism of how it regulates splicing will add to our understanding about how regulators of gene expression shape the transcriptome differentially between males and females. We tested our hypothesis by identifying CLAMP dependent female and male sex-specific splicing events by analysing RNA-seq data from control as well as clampnull mutant male and female third instar larvae (L3) using suppa based time2splice pipeline (https://github.com/ashleymaeconard/time2splice). We identified 189 and 211 CLAMP dependent splicing events in female and male L3. Out of these 139 were female sex-specific splicing whereas 161 was male-sex-specific splicing. 50 splicing events identified as CLAMP dependent were non-specific to any particular sex, and were affect in both the sexes. Interestingly, we identified splicing of master regulator of sex-determination sxl affected by absence of CLAMP in females whereas splicing of one of the sex-determination pathway effectors, tra regulated by CLAMP in males. These findings indicate CLAMP plays important role in determining sex-specific transcript diversity in Drosophila.
2023-08-02 | GSE220455 | GEO
Project description:Synergistic interactions between CLAMP and MSL complex facilitate Drosophila dosage compensation
| PRJNA170445 | ENA
Project description:The essential process of dosage compensation, which corrects for the imbalance in X-linked gene expression between XX females and XY males, represents a key model for how genes are targeted for coordinated regulation. However, the mechanism by which dosage compensation complexes identify the X-chromosome during early development remained unknown because of the difficulty of sexing embryos prior to zygotic transcription. We used meiotic drive to sex Drosophila embryos prior to zygotic transcription and ChIP-seq to measure dynamics of dosage compensation factor targeting. The Drosophila Male-Specific Lethal dosage compensation complex (MSLc) requires the ubiquitous zinc-finger protein Chromatin-Linked Adaptor for MSL Proteins (CLAMP) to identify the X-chromosome. We observe a multi-stage process in which MSLc first identifies CLAMP binding sites throughout the genome followed by concentration at the strongest X-linked MSLc sites. We provide insight into the dynamic mechanism by which a large transcription complex identifies its binding sites during early development.
2019-12-01 | GSE133637 | 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
2007-09-20 | GSE8557 | GEO