TPR is required for cytoplasmic chromatin fragment formation during senescence
Abstract
During oncogene-induced senescence there are striking changes in the organisation of heterochromatin in the nucleus. This is accompanied by activation of a pro-inflammatory gene expression programme - the senescence associated secretory phenotype (SASP) - driven by transcription factors such as NF-κB. The relationship between heterochromatin re-organisation and the SASP has been unclear. Here we show that TPR, a protein of the nuclear pore complex basket required for heterochromatin re-organisation during senescence, is also required for the very early activation of NF-κB signalling during the stress-response phase of oncogene-induced senescence. This is prior to activation of the SASP and occurs without affecting NF-κB nuclear import. We show that TPR is required for the activation of innate immune signalling at these early stages of senescence and we link this to the formation of heterochromatin-enriched cytoplasmic chromatin fragments thought to bleb off from the nuclear periphery. We show that HMGA1 is also required for cytoplasmic chromatin fragment formation. Together these data suggest that re-organisation of heterochromatin is involved in altered structural integrity of the nuclear periphery during senescence, and that this can lead to activation of cytoplasmic nucleic acid sensing, NF-κB signalling, and activation of the SASP.
Data availability
The RNA-seq and ATAC-seq data generated in this study have been deposited in NCBI GEO, but the data are currently private. Access tokens for reviewers to access these submission data are:RNA seqhttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE264387Access token: qzihsgiwhlqvzopATAC seqhttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE264390Access token: irstugcgzfqrlib
-
TPR is required for cytoplasmic chromatin fragment formation during senescenceNCBI Gene Expression Omnibus, GSE264387.
-
TPR is required for cytoplasmic chromatin fragment formation during senescenceNCBI Gene Expression Omnibus, GSE264390.
-
H3K27ac ChIP-seqNCBI Gene Expression Omnibus, GSE103590.
Article and author information
Author details
Funding
Medical Research Council (MC_UU_00007/2)
- Wendy A Bickmore
Medical Research Council (MC_UU_00035/7)
- Wendy A Bickmore
Wellcome Trust (217120/Z/19/Z)
- Yatendra Kumar
- Wendy A Bickmore
Cancer Research UK (C47559/A16243)
- Juan Carlos Acosta
Ministry of Science and Innovation, Government of Spain (Proyecto PID2020-117860GB-I00)
- Juan Carlos Acosta
Agence Nationale de la Recherche (ANR-21-CE12-0039)
- Charlene Boumendil
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2024, Bartlett et al.
This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.
Metrics
-
- 236
- views
-
- 86
- downloads
-
- 0
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
Further reading
-
- Cell Biology
Dystrophin is a critical interacting protein of Nav1.5 that determines its membrane anchoring in cardiomyocytes. Long noncoding RNAs (lncRNAs) are involved in the regulation of cardiac ion channels, while their influence on sodium channels remains unexplored. Our preliminary data showed that lncRNA-Dachshund homolog 1 (lncDach1) can bind to dystrophin, which drove us to investigate if lncDach1 can regulate sodium channels by interfering with dystrophin. Western blot and immunofluorescent staining showed that cardiomyocyte-specific transgenic overexpression of lncDach1 (lncDach1-TG) reduced the membrane distribution of dystrophin and Nav1.5 in cardiomyocytes. Meanwhile, peak INa was reduced in the hearts of lncDach1-TG mice than wild-type (WT) controls. The opposite data of western blot, immunofluorescent staining and patch clamp were collected from lncDach1 cardiomyocyte conditional knockout (lncDach1-cKO) mice. Moreover, increased ventricular arrhythmia susceptibility was observed in lncDach1-TG mice in vivo and ex vivo. The conservative fragment of lncDach1 inhibited membrane distribution of dystrophin and Nav1.5, and promoted the inducibility of ventricular arrhythmia. Strikingly, activation of Dystrophin transcription by dCas9-SAM system in lncDach1-TG mice rescued the impaired membrane distribution of dystrophin and Nav1.5, and prevented the occurrence of ventricular arrhythmia. Furthermore, lncDach1 was increased in transaortic constriction (TAC) induced failing hearts, which promoted the inducibility of ventricular arrhythmia. And the expression of lncDach1 is regulated by hydroxyacyl-CoA dehydrogenase subunit beta (hadhb), which binds to lncDach1 and decreases its stability. The human homologue of lncDACH1 inhibited the membrane distribution of Nav1.5 in human iPS-differentiated cardiomyocytes. The findings provide novel insights into the mechanism of Nav1.5 membrane targeting and the development of ventricular arrhythmias.
-
- Cancer Biology
- Cell Biology
TIPE (TNFAIP8) has been identified as an oncogene and participates in tumor biology. However, how its role in the metabolism of tumor cells during melanoma development remains unclear. Here, we demonstrated that TIPE promoted glycolysis by interacting with pyruvate kinase M2 (PKM2) in melanoma. We found that TIPE-induced PKM2 dimerization, thereby facilitating its translocation from the cytoplasm to the nucleus. TIPE-mediated PKM2 dimerization consequently promoted HIF-1α activation and glycolysis, which contributed to melanoma progression and increased its stemness features. Notably, TIPE specifically phosphorylated PKM2 at Ser 37 in an extracellular signal-regulated kinase (ERK)-dependent manner. Consistently, the expression of TIPE was positively correlated with the levels of PKM2 Ser37 phosphorylation and cancer stem cell (CSC) markers in melanoma tissues from clinical samples and tumor bearing mice. In summary, our findings indicate that the TIPE/PKM2/HIF-1α signaling pathway plays a pivotal role in promoting CSC properties by facilitating the glycolysis, which would provide a promising therapeutic target for melanoma intervention.