Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Diverging principles of selective sex chromosome regulation during evolution of Drosophila

ABSTRACT: The dosage compensation complex (DCC) of Drosophila identifies its X chromosomal binding sites with exquisite selectivity. The principles that assure this vital targeting are known from the D. melanogaster model: DCC-intrinsic specificity of DNA binding, cooperativity with the CLAMP protein, and non-coding roX2 RNA transcribed from the X chromosome. We found that in D. virilis, a species separated from melanogaster by 40 million years of evolution, all principles are active, but contribute differently to X-specificity. In melanogaster, the DCC subunit MSL2 evolved intrinsic DNA-binding selectivity for rare PionX sites, which mark the X chromosome. In virilis, PionX sites are abundant and not X-enriched. Accordingly, MSL2 lacks specific recognition. Here, roX2 RNA plays a more instructive role, counteracting a non-productive interaction of CLAMP and modulating DCC binding selectivity. Remarkably, roX2 triggers a low-diffusion chromatin binding mode characteristic of DCC. Evidently, X-specific regulation is achieved by divergent evolution of similar components.

ORGANISM(S): Drosophila virilis Drosophila melanogaster

PROVIDER: GSE165833 | GEO | 2021/07/07

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Similar Datasets

Divergent evolutionary strategies for selective sex chromosome regulation in Drosophila

Project description:The dosage compensation complex (DCC) of Drosophila identifies its X chromosomal binding sites with exquisite selectivity. The principles that assure this vital targeting are known from the D. melanogaster model: DCC-intrinsic specificity of DNA binding, cooperativity with the CLAMP protein, and non-coding roX2 RNA transcribed from the X chromosome. We found that in D. virilis, a species separated from melanogaster by 40 million years of evolution, all principles are active, but contribute differently to X-specificity. In melanogaster, the DCC subunit MSL2 evolved intrinsic DNA-binding selectivity for rare PionX sites, which mark the X chromosome. In virilis, PionX sites are abundant and not X-enriched. Accordingly, MSL2 lacks specific recognition. Here, roX2 RNA plays a more instructive role, counteracting a non-productive interaction of CLAMP and modulating DCC binding selectivity. Remarkably, roX2 triggers a low-diffusion chromatin binding mode characteristic of DCC. Evidently, X-specific regulation is achieved by divergent evolution of similar components.

2021-06-23 | PXD023747 | Pride

Mechanism of selective incorporation of lncRNA into a chromatin modifier

Project description:The MLE DExH helicase and the roX lncRNAs are essential components of the chromatin modifying Dosage Compensation Complex (DCC) in Drosophila. To explore the mechanism of ribonucleoprotein complex assembly, we designed vitRIP, an unbiased, transcriptome-wide in vitro assay that reveals RNA binding specificity. We found that MLE has intrinsic specificity for U-rich sequences and tandem stem-loop structures. In vitro, the helicase binds and remodels many RNAs beyond its main target, roX2. Unwinding of roX2 by the helicase triggers their selective association with the DCC, via the MSL2 subunit. Whereas the core DCC alone does not show intrinsic RNA binding specificity, the presentation of remodeled roX2 by MLE induces a highly selective RNA binding surface in the unstructured C-terminus of MSL2. The exquisite selectivity of roX2 incorporation into the DCC thus originates from intimate cooperation between the helicase and the core DCC involving two distinct RNA selection principles and their mutual refinement.

2020-05-27 | GSE143455 | GEO

Factor cooperation for chromosome discrimination in Drosophila

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

MSL2 reads DNA shape to distinguish X from autosome for dosage compensation (SXL RNAi in Kc cells experiments)

Project description:The rules according to which transcription factors selectively bind only a small subset of genomic sites from a vast pool of similar sequences are not understood. One of the most challenging tasks in DNA recognition is posed by dosage compensation systems that require the unequivocal distinction between a sex chromosome and all autosomes. In Drosophila melanogaster the male-specific-lethal dosage compensation complex (MSL-DCC) doubles the transcription output of most genes on the X chromosome via chromatin modification, but the nature of this selectivity is not known. We now found that MSL2, the male-specific organizer of the DCC, uses two distinct DNA interaction surfaces to read out previously identified X chromosomal ‘high affinity sites’. Specificity is provided by the interaction of the CXC domain with a novel, X-specific motif defined by DNA sequence and shape features. By several criteria these ‘PionX sites’ are primary determinants of X chromosome identity.

2016-08-30 | GSE75031 | GEO

MSL2 reads DNA shape to distinguish X from autosome for dosage compensation (DIP experiments)

2016-08-30 | GSE75030 | GEO

MSL2 reads DNA shape to distinguish X from autosome for dosage compensation (MLE RNAi in S2 cells experiments)

2016-08-30 | GSE75032 | GEO

MSL2 cut and run profiles in S2 cell lines

Project description:MSL2, the DNA-binding subunit of the Drosophila dosage compensation complex, cooperates with the ubiquitous protein CLAMP to bind MSL recognition elements (MREs) on the X chromosome. We explore the nature of the cooperative binding to these GA-rich, composite sequence elements in reconstituted naïve embryonic chromatin. We found that the cooperativity requires physical interaction between both proteins. Remarkably, disruption of this interaction does not lead to indirect, nucleosome-mediated cooperativity as expected, but to competition. The protein interaction apparently not only increases the affinity for composite binding sites, but also locks both proteins in a defined dimeric state that prevents competition. High Affinity Sites of MSL2 on the X chromosome contain variable numbers of MREs. We find that the cooperation between MSL2/CLAMP is not influenced by MRE clustering or arrangement, but happens largely at the level of individual MREs. The sites where MSL2/CLAMP bind strongly in vitro locate to all chromosomes and show little overlap to an expanded set of X-chromosomal MSL2 in vivo binding sites generated by CUT&RUN. Apparently, the intrinsic MSL2/CLAMP cooperativity is limited to a small selection of potential sites in vivo. This restriction must be due to components missing in our reconstitution, such as roX2 lncRNA.

2023-07-27 | GSE228935 | GEO

roX ChIRP-seq in four Drosophila species

Project description:We identified orthologs of the roX lncRNAs across diverse Drosophilid species, and then mapped the genomic binding sites of roX1 and roX2 in four Drosophila species (D. melanogaster, D. willistoni, D. virilis, and D. busckii) using ChIRP-seq (chromatin isolation by RNA Purification and sequencing), thus revealing the interplay of the evolution of roX1 and roX2 and their genomic binding sites.

2016-01-25 | GSE69208 | GEO

N-terminus of Drosophila MSL1 interacts with DNA-binding proteins and is critical for the recruitment of the dosage compensation complex to the X chromosome

Project description:The male-specific lethal dosage compensation complex (MSL complex or DCC), which consists of five proteins and two non-coding roX RNAs, is necessary for the transcriptional enhancement of X-linked genes to compensate for the sex chromosome monosomy in Drosophila XY males, compared with XX females. MSL2 is a single protein component of the DCC that is expressed only in males and is essential for the specific recruitment of the DCC to the high-affinity “entry” sites (HASs) on the X chromosome. MSL2, together with MSL1, forms the heterotetrameric DCC core. Here, we demonstrated that the N-terminal unstructured region of MSL1 interacts with many different DNA-binding proteins that contain clusters of the C2H2 zinc-finger domains. Amino acid deletions in the N-terminal region of MSL1 strongly affect the binding of the DCC to the HASs on the male X chromosome. However, the binding of MSL2 to autosomal promoters was unaffected by amino acid deletions in MSL1. Males expressing mutant variants of MSL1 died during the larvae stage, demonstrating the critical role played by the N-terminal region in DCC activity. Our results suggest that MSL1 interacts with a variety of DNA-binding proteins to increase the specificity of DCC recruitment to the male X chromosome.

2022-08-30 | GSE161128 | GEO

The Drosophila Dosage Compensation Complex activates target genes via chromosome looping within the active compartment

Project description:X chromosome dosage compensation in Drosophila requires chromosome-wide coordination of gene activation. The male-specific-lethal dosage compensation complex (DCC) identifies X chromosomal High Affinity Sites (HAS) from which it reaches out to boost transcription. A recently discovered sub-class of HAS, PionX sites, represent first contacts on the X. We explored the chromosomal interactions of representative PionX sites by high-resolution 4C methodology and determined the overall chromosome conformation by Hi-C in sex-sorted embryos. X chromosomes from male and female cells display similar nuclear architecture, concordant with clustered, constitutively active genes. PionX sites, like HAS, are evenly distributed in the active compartment and engage in short- and long-range interactions beyond compartment boundaries. De novo induction of DCC in female cells allowed monitoring the reach of activation surrounding PionX sites. Remarkably, DCC not only activates genes in linear proximity, but also at megabase distance if close in space, suggesting that dosage compensation profits from chromosome folding.

2017-07-01 | GSE94115 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data