Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Centromere protection requires strict mitotic inactivation of the Bloom syndrome helicase complex

ABSTRACT: The BTRR (BLM/TOP3A/RMI1/RMI2) complex resolves various DNA replication and recombination intermediates to suppress genome instability. Alongside PICH, they target mitotic DNA intertwinements, known as ultrafine DNA bridges, facilitating chromosome segregation. Both BLM and PICH undergo transient mitotic hyper-phosphorylation, but the biological significance of this remains elusive. Here, we uncover that during early mitosis, multiple protein kinases act together to strictly constrain the BTRR complex for the protection of centromeres. Mechanistically, CDK1 destabilises the complex and suppresses its association with PICH at the chromatin underneath kinetochores. Inactivating the BLM and TOP3A interaction compromises the UFB-binding complex mitotic functions and can prevent centromere destruction. We further unravel how different clusters of mitotic phosphorylation on BLM affect its interaction with the TOP3A/RMI1/RMI2 subcomplex and illegitimate centromere unwinding. Furthermore, we identify specific phosphorylation sites targeted by the MPS1-PLK1 axis functioning to prevent BLM hyper-activation at centromeres. Notably, unleashing such activity after sister-chromatid cohesion loss facilitates separation of entangled chromosomes. Together, our study defines a centromere protection pathway in human mitotic cells, heavily reliant on a tight spatiotemporal control of the BTRR complex.

INSTRUMENT(S):

ORGANISM(S): Homo Sapiens (human)

SUBMITTER: Graeme Benstead-Hume

LAB HEAD: Jyoti Choudhary

PROVIDER: PXD052850 | Pride | 2025-08-27

REPOSITORIES: Pride

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
	Req71-CC-Chan_GFP-BLM.pdStudy	Other
	Req71-CC-Chan_GFP-BLM.pdStudy.bak	Other
	Req71-CC-Chan_GFP-TOP3A.pdStudy	Other
	Req71-CC-Chan_GFP-TOP3A.pdStudy.bak	Other
	Req71-CC-Chan_H1_.msf	Msf

Items per page:

1 - 5 of 40

Similar Datasets

Centromere protection requires strict mitotic inactivation of the Bloom syndrome helicase complex

Project description:The BTRR (BLM/TOP3A/RMI1/RMI2) complex resolves various DNA replication and recombination intermediates to suppress genome instability. Alongside PICH, they target mitotic DNA intertwinements, known as ultrafine DNA bridges, facilitating chromosome segregation. Both BLM and PICH undergo transient mitotic hyper-phosphorylation, but the biological significance of this remains elusive. Here, we uncover that during early mitosis, multiple protein kinases act together to strictly constrain BTRR complex activities at centromeres. Mechanistically, CDK1 destabilises the complex and suppresses its association with PICH at the chromatin underneath kinetochores. Inactivating the BLM and TOP3A interaction compromises the UFB-binding complex mitotic functions and can prevent centromere destruction. We further unravel how different mitotic phosphorylation sites of BLM affect its interaction with the TOP3A/RMI1/RMI2 subcomplex and centromeric DNA unwinding. Furthermore, we show that multiple PLK1-mediated phosphorylation on BLM is required to suppress aberrant centromere unwinding. However, notably, unleashing such activity after sister-chromatid cohesion loss facilitates separation of entangled chromosomes. Together, our study defines a centromere protection pathway in human mitotic cells, heavily reliant on a tight spatiotemporal control of the BTRR complex.

2025-08-12 | PXD064192 | Pride

Centromere protection requires strict mitotic inactivation of the Bloom syndrome helicase complex

Project description:The BTRR (BLM/TOP3A/RMI1/RMI2) complex resolves various DNA replication and recombination intermediates to suppress genome instability. Alongside PICH, they target mitotic DNA intertwinements, known as ultrafine DNA bridges, facilitating chromosome segregation. Both BLM and PICH undergo transient mitotic hyper-phosphorylation, but the biological significance of this remains elusive. Here, we uncover that during early mitosis, multiple protein kinases act together to strictly constrain the BTRR complex for the protection of centromeres. Mechanistically, CDK1 destabilises the complex and suppresses its association with PICH at the chromatin underneath kinetochores. Inactivating the BLM and TOP3A interaction compromises the UFB-binding complex mitotic functions and can prevent centromere destruction. We further unravel how different clusters of mitotic phosphorylation on BLM affect its interaction with the TOP3A/RMI1/RMI2 subcomplex and illegitimate centromere unwinding. Furthermore, we identify specific phosphorylation sites targeted by the MPS1-PLK1 axis functioning to prevent BLM hyper-activation at centromeres. Notably, unleashing such activity after sister-chromatid cohesion loss facilitates separation of entangled chromosomes. Together, our study defines a centromere protection pathway in human mitotic cells, heavily reliant on a tight spatiotemporal control of the BTRR complex.

2025-08-12 | PXD052669 | Pride

The SUMO-NIP45 pathway guards against accumulation of toxic DNA catenanes

Project description:SUMOylation is an essential protein modification that regulates numerous biological processes, but what constitutes its most critical functions in the cell remains unclear. Here, using genome-scale CRISPR-Cas9-based synthetic lethality screens, we show that the BLM-TOP3A-RMI1-RMI2 (BTRR)-PICH pathway, which resolves ultra-fine anaphase DNA bridges (UFBs) arising from catenated DNA structures, and NIP45 (NFATC2IP) display a synthetic lethal interaction in human cells and are essential for proliferation when SUMOylation is impaired. NIP45 and SUMOylation prevent excessive UFB formation that leads to extensive binucleation when BTRR-PICH-dependent UFB resolution is defective, by orchestrating an interphase pathway for converting DNA catenanes into DNA double-strand breaks that trigger G2 arrest via canonical ATM/ATR-dependent DNA damage signaling. NIP45 exerts its crucial function in this pathway by acting as a cofactor for specific SUMOylation processes that are at least in part targeted to the SLX4 multi-nuclease complex, which may facilitate nucleolytic DNA catenane resolution. Our findings establish an essential role of SUMO signaling in underpinning cell proliferation by counteracting the deleterious threat to faithful chromosome segregation posed by toxic DNA catenanes arising in virtually every cell cycle, via non-epistatic NIP45- and BTRR-PICH-dependent pathways.

2023-07-21 | PXD033739 | Pride

Proteolytic Cleavage Activates the Mitochondrial Isoform of TOP3A

Project description:The TOP3A gene encodes two isoforms, one targeted to the nucleus and one to mitochondria. Nuclear TOP3A functions as part of the BTRR complex to resolve double Holliday junctions during homologous recombination, while the mitochondrial isoform separates hemicatenated daughter mitochondrial DNA molecules following DNA replication. Here, we show that the mitochondrial isoform of TOP3A undergoes proteolytic cleavage by the mitochondrial processing peptidase (MPP), removing ~90 amino acids from the C-terminus. This cleavage enhances the enzyme’s biochemical properties, increasing single-stranded DNA binding and decatenation activity. Notably, all BTRR complex subunits except TOP3A are absent from mitochondria, suggesting that proteolytic processing enables TOP3A to function autonomously in mtDNA maintenance. We propose that this cleavage represents a post-import maturation step that tailors TOP3A to its mitochondrial context by uncoupling it from nuclear protein interactions and enhancing its catalytic efficiency.

2025-10-01 | PXD064926 | Pride

Ho_BLM_TOP3A_RMI_BioID_P130_Velos_Elite

Project description:This dataset consists of 25 raw MS files and associated peak lists and results files, acquired on a Thermo LTQ Velos Pro or Thermo Orbitrap Elite mass spectrometer operated in Data Dependent Acquisition mode. Samples were generated by Edith Cheng. Affinity purifications and mass spectrometry acquisition was performed by Wade Dunham. Analysis was performed by Jennifer Ho, Wade Dunham, Edith Cheng, Cassandra Wong, Anne-Claude Gingras, and Grant Brown. The files are associated with a manuscript submitted for publication by Jung Jennifer Ho et al. The main goal of this paper was to profile the proximity interactome of BLM-TOP3A-RMI1-RMI2 (BTRR) complex to identify proteins that suppress recombination in DNA repair. This dataset identifies the importance of RAD54L2 for the recruitment of Bloom (BLM) helicase to promote non-crossover recombination. Grant W. Brown is the corresponding author of the manuscript (grant.brown@utoronto.ca); Anne-Claude Gingras should be contacted for questions on this dataset (gingras@lunenfeld.ca)

2024-01-16 | MSV000093876 | MassIVE

A CPC-shelterin-BTR axis regulates mitotic telomere deprotection

Project description:Telomeres prevent ATM activation by sequestering chromosome termini within telomere loops (t-loops). Mitotic arrest promotes telomere linearity and a localized ATM-dependent telomere DNA damage response (DDR) through an unknown mechanism. Using unbiased interactomics, biochemical screening, molecular biology, and super-resolution imaging, we found that mitotic arrest-dependent (MAD) telomere deprotection requires the combined activities of the Chromosome passenger complex (CPC) on shelterin, and the BLM-TOP3A-RMI1/2 (BTR) complex on t-loops. During mitotic arrest, the CPC component Aurora Kinase B (AURKB) phosphorylated both the TRF1 hinge and TRF2 basic domains. Phosphorylation of the TRF1 hinge domain enhances CPC and TRF1 interaction through the CPC Survivin subunit. Meanwhile, phosphorylation of the TRF2 basic domain promotes telomere linearity, activates a telomere DDR dependent on BTR-mediated double Holliday junction dissolution, and leads to mitotic death. We identify that the TRF2 basic domain functions in mitosis-specific telomere protection and reveal a regulatory role for TRF1 in controlling a physiological ATM-dependent telomere DDR. The data demonstrate that MAD telomere deprotection is a sophisticated active mechanism that exposes telomere ends to signal mitotic stress.

2025-01-28 | PXD043281 | Pride

The FIGNL1-interacting protein C1orf112 is synthetic lethal with PICH and mediates RAD51 retention on chromatin

Project description:Joint DNA molecules are natural by-products of DNA replication and repair. Persistent joint molecules give rise to ultrafine DNA bridges (UFBs) in mitosis, which compromise sister chromatid separation. The DNA translocase PICH (ERCC6L) plays a central role in UFB resolution. To better understand the genetic context rendering cells dependent on PICH, a genome-wide loss-of-function screen was performed to identify the genetic contexts in which cells become dependent on PICH. In addition to genes involved in DNA cohesion, centromere stability and DNA damage repair, we identified the uncharacterized protein C1orf112. We find that C1orf112 interacts with and stabilizes the AAA+ ATPase FIGNL1. Inactivation of either C1orf112 or FIGNL1 resulted in UFB formation, prolonged retention of RAD51 on chromatin, impaired replication fork dynamics, and consequently impaired genome maintenance. Combined, our data reveal that inactivation of C1orf112 or FIGNL1 dysregulates RAD51 dynamics at replication forks, resulting in DNA replication defects, and a dependency on PICH to preserve cell viability.

2024-08-08 | PXD035876 | Pride

Transcriptomic analysis to identify the putative genes under the regulation of two component system BtrK/BtrR in C. acetobutylicum

Project description:To identify the putative genes under the regulation of two component system BtrK/BtrR, we performed a comparative transcriptomic analysis of the BtrK/BtrR overexpressing strain and the contron strain. Finally, we found that BtrK/BtrR was a global regulator and exerted pleiotropic regulatory role in C. acetobutylicum

2019-10-08 | GSE138466 | GEO

Specialized replication mechanisms maintain genome stability at human centromeres

Project description:Reveal a specific set of proteins important to maintain centromere integrity, through quantitative PICh (Proteomics of Isolated Chromatin). Centromeric chromatin was pulled down through RNA probes annealing specifically to a 300bp-long conserved centromeric sequence.

2024-02-14 | PXD047847 | Pride

RNA sequencing of HeLa cells

Project description:DNA topoisomerase 3A (TOP3A) and mitochondrial DNA topoisomerase 1 (TOP1MT) play an important role in the maintenance and topological control of the mitochondrial DNA. In this study TOP3A, TOP1MT or both TOP3A and TOP1MT have been knocked down using siRNAs to determine the effect of the topoisomerases on mitochondrial transcription. RNA was isolated from ctrl siRNA, TOP3A siRNA, TOP1MT siRNA and TOP3A + TOP1MT siRNA transfected cells after 6 days of transfection.

2022-10-11 | GSE201426 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

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