A high-content screen reveals new regulators of nuclear membrane stability DOI Creative Commons
Amanda Gunn, Artem I. Yashchenko, Julien Dubrulle

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: May 31, 2023

Nuclear membrane rupture is a physiological response to multiple in vivo processes, such as cell migration, that can cause extensive genome instability and upregulate invasive inflammatory pathways. However, the underlying molecular mechanisms of are unclear few regulators have been identified. In this study, we developed reporter size excluded from re-compartmentalization following nuclear events. This allows for robust detection factors influencing integrity fixed cells. We combined with an automated image analysis pipeline high-content siRNA screen identify new proteins both increase decrease frequency cancer Pathway identified enrichment ER our hits demonstrate one these, protein phosphatase CTDNEP1, required stability. Further known contributors, including newly quantitative lamina gaps, strongly suggests CTDNEP1 acts pathway. Our findings provide insights into mechanism define highly adaptable program removes substantial barrier discoveries field.

Language: Английский

Chromatin phase separation and nuclear shape fluctuations are correlated in a polymer model of the nucleus DOI Creative Commons
Ali Goktug Attar, Jarosław Paturej, Edward J. Banigan

et al.

Nucleus, Journal Year: 2024, Volume and Issue: 15(1)

Published: May 16, 2024

Abnormal cell nuclear shapes are hallmarks of diseases, including progeria, muscular dystrophy, and many cancers. Experiments have shown that disruption heterochromatin increases in euchromatin lead to deformations, such as blebs ruptures. However, the physical mechanisms through which chromatin governs shape poorly understood. To investigate how might govern morphology, we studied microphase separation a composite coarse-grained polymer elastic shell simulation model. By varying density, composition, heterochromatin-lamina interactions, show phase organization may perturb shape. Increasing density stabilizes lamina against large fluctuations. increasing levels or interactions enhances fluctuations by "wetting"-like interaction. In contrast, insensitive heterochromatin's internal structure. Our simulations suggest peripheral accumulation could while stabilization likely occurs other than organization.

Language: Английский

Citations

9
Constitutive heterochromatin controls nuclear mechanics, morphology, and integrity through H3K9me3 mediated chromocenter compaction DOI Creative Commons
Gerard Manning, Andrew A. Li,

Nebiyat Eskndir

et al.

Nucleus, Journal Year: 2025, Volume and Issue: 16(1)

Published: April 9, 2025

Language: Английский

Citations

1
Transcription inhibition suppresses nuclear blebbing and rupture independently of nuclear rigidity DOI Creative Commons

Isabel K. Berg,

Marilena L. Currey,

Sarthak Gupta

et al.

Journal of Cell Science, Journal Year: 2023, Volume and Issue: 136(20)

Published: Sept. 27, 2023

Chromatin plays an essential role in the nuclear mechanical response and determining shape, which maintain compartmentalization function. However, major genomic functions, such as transcription activity, might also impact cell shape via blebbing rupture through their effects on chromatin structure dynamics. To test this idea, we inhibited with several RNA polymerase II inhibitors wild-type cells perturbed that presented increased blebbing. Transcription inhibition suppressed for types, perturbations inhibitors. Furthermore, bleb formation, stabilization bleb-based ruptures. Interestingly, did not alter histone H3 lysine 9 (H3K9) modification state, rigidity, actin compression contraction, typically control Polymer simulations suggested motor activity within could drive motions deform periphery. Our data provide evidence suppresses rupture, a manner separate distinct from rigidity.

Language: Английский

Citations

14
A high-content screen reveals new regulators of nuclear membrane stability DOI Creative Commons
Amanda Gunn, Artem I. Yashchenko, Julien Dubrulle

et al.

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: March 12, 2024

Abstract Nuclear membrane rupture is a physiological response to multiple in vivo processes, such as cell migration, that can cause extensive genome instability and upregulate invasive inflammatory pathways. However, the underlying molecular mechanisms of are unclear few regulators have been identified. In this study, we developed reporter size excluded from re-compartmentalization following nuclear events. This allows for robust detection factors influencing integrity fixed cells. We combined with an automated image analysis pipeline high-content siRNA screen identify new proteins both increase decrease frequency cancer Pathway identified enrichment ER our hits demonstrate one these, protein phosphatase CTDNEP1, required stability. Analysis known determinants, including quantitative lamina gaps, consistent CTDNEP1 acting independently actin organization. Our findings provide insights into mechanism define highly adaptable program removes substantial barrier discoveries field.

Language: Английский

Citations

4
DNA density is a better indicator of a nuclear bleb than lamin B loss DOI Creative Commons

Samantha Bunner,

Kelsey Prince,

Karan Srikrishna

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Feb. 7, 2024

Nuclear blebs are herniations of the nucleus that occur in diseased nuclei cause nuclear rupture leading to cellular dysfunction. Chromatin and lamins two major structural components maintain its shape function, but their relative roles blebbing remain elusive. Lamin B is reported be lost by qualitative data while quantitative studies reveal a spectrum lamin levels dependent on perturbation cell type. has been decreased or de-compacted blebs, again not conclusive. To determine composition we compared immunofluorescence intensity DNA main body bleb across types perturbations. varied drastically MEF wild type chromatin perturbations, HCT116 B1-GFP imaging, human disease model cells progeria prostate cancer. However, concentration was consistently about half all measured conditions. Using Partial Wave Spectroscopic (PWS) microscopy measure density vs find similar results less dense blebs. Thus, our spanning many different perturbations supports better marker than vary widely.

Language: Английский

Citations

3
DNA damage causes ATM-dependent heterochromatin loss leading to nuclear softening, blebbing, and rupture DOI Creative Commons

Nebiyat Eskndir,

Manseeb Hossain,

Marilena L. Currey

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: May 29, 2024

The nucleus must maintain stiffness to protect the shape and integrity of ensure proper function. Defects in nuclear caused from chromatin lamin perturbations produce abnormal shapes common aging, heart disease, cancer. Loss via protrusions called blebs leads rupture that is well-established cause dysfunction, including DNA damage. However, it remains unknown how increased damage affects stiffness, shape, ruptures, which could create a negative feedback loop. To determine if alters physical properties, we treated MEF cells with drugs cisplatin bleomycin. blebbing interphase nuclei within few hours independent mitosis. Micromanipulation force measurements reveal decreased chromatin-based mechanics but did not change lamin-based strain stiffening at long extensions relative wild type. Immunofluorescence treatments mechanism an ATM-dependent decrease heterochromatin leading weaken, blebbing, can be rescued upon ATM inhibition treatment. Thus, loss resulting softening, rupture.

Language: Английский

Citations

3
The dynamic nuclear envelope: resilience in health and dysfunction in disease DOI Creative Commons

Ayse M. Turkmen,

Natasha O. Saik, Katharine S. Ullman

et al.

Current Opinion in Cell Biology, Journal Year: 2023, Volume and Issue: 85, P. 102230 - 102230

Published: Aug. 31, 2023

The canonical appearance of the nucleus depends on constant adaptation and remodeling nuclear envelope in response to changing biomechanical forces metabolic demands. Dynamic events at play a vital role supporting key functions as well conferring plasticity this organelle. Moreover, imbalance these dynamic processes is emerging central feature disease etiology. This review focuses recent advances that shed light myriad contribute resilience flexibility architecture.

Language: Английский

Citations

7
Nuclear shape is affected differentially by loss of lamin A, lamin C, or both lamin A and C. DOI

Mai Pho,

Yasmin Berrada,

Aachal Gunda

et al.

PubMed, Journal Year: 2024, Volume and Issue: 2024

Published: Jan. 1, 2024

Lamin intermediate filaments form a peripheral meshwork to support nuclear shape and function. Knockout of the LMNA gene that encodes for both lamin A C results in an abnormally shaped nucleus. To determine relative contribution shape, we measured blebbing circular deviation separate knockdown LMNA-/- stable cells. increased while loss A, C, or deviation. Overall, A/C affect differentially.

Language: Английский

Citations

2
Emerin mislocalization during chromatin bridge resolution can drive prostate cancer cell invasiveness in a collagen-rich microenvironment DOI Creative Commons
Marta Popęda, Kamil Kowalski, Tomasz Wenta

et al.

Experimental & Molecular Medicine, Journal Year: 2024, Volume and Issue: 56(9), P. 2016 - 2032

Published: Sept. 2, 2024

Abstract Micronuclei (MN) can form through many mechanisms, including the breakage of aberrant cytokinetic chromatin bridges. The frequent observation MN in tumors suggests that they might not merely be passive elements but could instead play active roles tumor progression. Here, we propose a mechanism which presence micronuclei induce specific phenotypic and functional changes cells increase invasive potential cancer cells. Through integration diverse vitro imaging molecular techniques supported by clinical samples from patients with prostate (PCa) defined as high-risk D’Amico classification, demonstrate resolution chromosome bridges result accumulation Emerin formation Emerin-rich MN. These structures are negative for Lamin A/C positive Lamin-B receptor Sec61β. act protein sinks pauperization nuclear envelope. mislocalization phenotype is associated signature correlated poor prognosis PCa enriched metastatic samples. corresponds increases migratory cells, especially collagen-rich microenvironment. Our study demonstrates to results increased cell invasiveness, thereby worsening patient prognosis.

Language: Английский

Citations

2
Nuclear blebs are associated with destabilized chromatin packing domains DOI Open Access
Emily M. Pujadas-Liwag, Nicolas Acosta, Luay M. Almassalha

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: March 29, 2024

ABSTRACT Disrupted nuclear shape is associated with multiple pathological processes including premature aging disorders, cancer-relevant chromosomal rearrangements, and DNA damage. Nuclear blebs (i.e., herniations of the envelope) have been induced by (1) compression, (2) migration (e.g., cancer metastasis), (3) actin contraction, (4) lamin mutation or depletion, (5) heterochromatin enzyme inhibition. Recent work has shown that chromatin transformation a hallmark bleb formation, but higher-order structures in not well understood. As to assemble into nanoscopic packing domains, we investigated if domain organization altered within alteration structure contributed formation. Using Dual-Partial Wave Spectroscopic microscopy, show domains are transformed both B-type depletion inhibition enzymes compared body. Pairing these results single-molecule localization microscopy constitutive heterochromatin, fragmentation domains. Overall, findings indicate translocation fragmented structure. SUMMARY STATEMENT linked various pathologies, disorders. We investigate alterations blebs, revealing

Language: Английский

Citations

1