Nuclear organization

  • Article
    | Open Access

    Self-interacting chromatin domains encompass genes and their cis-regulatory elements. Here the authors use high-resolution chromosome conformation capture and super-resolution imaging to study a 70 kb domain that includes the mouse α-globin regulatory locus and find that a tissue-specific self-interacting chromatin domain forms independently of enhancer-promoter interactions.

    • Jill M. Brown
    • , Nigel A. Roberts
    •  & Veronica J. Buckle
  • Article
    | Open Access

    Lamina-associated domains (LADs) contact lamins in the nuclear lamina, and lamin B1 was thought to bind heterochromatic regions at the nuclear envelope. Here, the authors show lamin B1 associates with actively expressed euchromatin regions, creating dynamic euchromatin lamina-associated domains (eLADs) during epithelial-to-mesenchymal transition.

    • Laura Pascual-Reguant
    • , Enrique Blanco
    •  & Sandra Peiró
  • Article
    | Open Access

    Many RNA viruses that replicate in the cytoplasm express proteins that localize to nucleoli, but the nucleolar functions remain largely unknown. Here, the authors show that the Henipavirus matrix protein mimics an endogenous Treacle partner of the DNA-damage response, resulting in suppression of rRNA biogenesis.

    • Stephen M. Rawlinson
    • , Tianyue Zhao
    •  & Gregory W. Moseley
  • Article
    | Open Access

    The perinuclear actin cap determines nuclear morphology but its regulation is currently poorly understood. Here, the authors find that an activator of the Rac1 GTPase, STEF/TIAM2, localises to the nuclear envelope and contributes to perinuclear actin and myosin tension, which in turn regulates the actin cap.

    • Anna Woroniuk
    • , Andrew Porter
    •  & Angeliki Malliri
  • Article
    | Open Access

    The development of malaria parasites is controlled by coordinated changes in gene expression. Here, the authors show that the three-dimensional genome structure of human malaria parasites is strongly connected with transcriptional activity of specific gene families throughout the life cycles of Plasmodium falciparum and Plasmodium vivax parasites.

    • Evelien M. Bunnik
    • , Kate B. Cook
    •  & Karine G. Le Roch
  • Article
    | Open Access

    Although CTCF binding has been implicated in the formation of topologically associated domains (TADs) the mechanisms folding the genome into TADs are not fully understood. Here the authors investigate the TAD boundary on lncRNA locus Firre, which has ~ 15 CTCF binding sites, and its organization.

    • A. Rasim Barutcu
    • , Philipp G. Maass
    •  & John L. Rinn
  • Article
    | Open Access

    The inactive X chromosome condenses into a bipartite structure. Here the authors use cells with allelic deletions or inversions to show that the Dxz4 locus is necessary to maintain the bipartite structure and that Dxz4 orientation controls the distribution of contacts on the inactive X chromosome.

    • G. Bonora
    • , X. Deng
    •  & C. M. Disteche
  • Article
    | Open Access

    Rbfox1, a pro-survival RNA-binding protein, is expressed in a complex manner and mediates diverse developmental processes. Here, the authors observe alternative splicing of Rbfox1 and stress-dependent regulation by miR-980 in Drosophila ovaries and Rbfox1 localisation in ribonucleoprotein granules in human cells.

    • Mariya M. Kucherenko
    •  & Halyna R. Shcherbata
  • Article
    | Open Access

    An actin cap protects the morphology of the nucleus during cellular mechanical stress. Here, the authors show that the nuclear lamina protein lamin A/C mediates the formation of the actin cap in response to stress, and model the distribution of forces in the presence and absence of the actin cap.

    • Jeong-Ki Kim
    • , Arghavan Louhghalam
    •  & Dong-Hwee Kim
  • Article
    | Open Access

    Phosphoinositides are enriched in the nucleus and accumulate upon DNA damage but their role in responding to DNA damage is poorly defined. Here, the authors show that phosphoinositides rapidly accumulate at DNA damage sites and are required for ATR recruitment and subsequent Chk1 activation.

    • Yu-Hsiu Wang
    • , Anushya Hariharan
    •  & Michael P. Sheetz
  • Article
    | Open Access

    Stable intronic sequence RNAs (sisRNAs) are by-products of splicing from introns with roles in embryonic development in Drosophila. Here, the authors show that the RNA binding protein DIP1 regulates sisRNAs in Drosophila, which is necessary for germline stem cell homeostasis.

    • Jing Ting Wong
    • , Farzanah Akhbar
    •  & Jun Wei Pek
  • Article
    | Open Access

    Cytidine deaminase (CDA) deficiency leads to genome instability. Here the authors find a synthetic lethal interaction between CDA and the microtubule-associated protein Tau deficiencies, and report that Tau depletion affects rRNA synthesis, ribonucleotide pool balance, and rDNA stability.

    • Elias Bou Samra
    • , Géraldine Buhagiar-Labarchède
    •  & Mounira Amor-Guéret
  • Article
    | Open Access

    Animal lifespan is plastic and is regulated by conserved signalling pathways. Here, Tikuet al.show that longevity-enhancing mutations or interventions are associated with reduced nucleolar size in worms, flies, mice and humans, and that nucleolar size can predict life-expectancy in individual worms.

    • Varnesh Tiku
    • , Chirag Jain
    •  & Adam Antebi
  • Article
    | Open Access

    HGPS is a premature aging disease caused by mutations in the nuclear protein lamin A. Here, the authors show that cells from patients with HGPS have expanded nucleoli and increased protein synthesis, and report that nucleoli also expand as aging progresses in cells derived from healthy individuals.

    • Abigail Buchwalter
    •  & Martin W. Hetzer
  • Article
    | Open Access

    Recent findings suggest that forces acting on the cell nucleus can cause DNA damage, but the mechanisms are unclear. Here Takakiet al. report that actomyosin is a determinant of nuclear shape and that unrestrained contractility elicits nuclear envelope rupture and genome instability in cancer cells.

    • Tohru Takaki
    • , Marco Montagner
    •  & Mark Petronczki
  • Article
    | Open Access

    Emerging evidence suggests that lamins regulate gene expression during cellular differentiation. Giganteet al. show that lamin B1 is necessary for the upregulation of mature neuron-specific genes during olfactory neuron differentiation, and its deficiency leads to attenuated olfactory neuron response to odour in mice.

    • Crystal M. Gigante
    • , Michele Dibattista
    •  & Haiqing Zhao
  • Article
    | Open Access

    Nucleoplasmic translocation of NPM1 is integral to nucleolar stress sensing. Here, the authors show that nucleolar oxidation is a general cellular stress response, and that oxidation-related glutathionylation of NPM1 triggers its translocation and facilitates p53 activation.

    • Kai Yang
    • , Ming Wang
    •  & Jing Yi
  • Article
    | Open Access

    Nuclear envelope transmembrane proteins (NETs) can reside in the outer or inner nuclear membrane, but distinguishing which membrane they reside in, and their translocation rate, is technically challenging. Here the authors develop a FRAP-based super-resolution microscopy method to obtain this information for several NETs.

    • Krishna C Mudumbi
    • , Eric C Schirmer
    •  & Weidong Yang
  • Article
    | Open Access

    In mature neurons the centrosome no longer functions as the main microtubule organizer and it is unclear how ordered microtubule arrays are assembled. Here, the authors show that in post-mitotic neurons this process depends on non-centrosomal nucleation mediated by the protein complex augmin and the nucleator gamma-TuRC.

    • Carlos Sánchez-Huertas
    • , Francisco Freixo
    •  & Jens Lüders
  • Article
    | Open Access

    Stress granules that form in response to stress contain translationally stalled mRNPs and play important roles in cellular homeostasis. Here the authors implicate SRSF3 neddylation as an important factor in the formation of stress granules in response to arsenite exposure.

    • Aravinth Kumar Jayabalan
    • , Anthony Sanchez
    •  & Takbum Ohn
  • Article
    | Open Access

    The nucleolus is a specialized functional domain of the nucleus where ribosome biogenesis is initiated and also implicated in a p53-dependent anti-tumor surveillance. Here the authors use a quantitative imaging approach to detail the role of each ribosomal protein on the structural integrity of the nucleolus and p53 homeostasis.

    • Emilien Nicolas
    • , Pascaline Parisot
    •  & Denis L. J. Lafontaine
  • Article
    | Open Access

    Nuclear bodies can nucleate at sites of active transcription and are beneficial for efficient gene expression. Here, the authors show that Cajal bodies, a prominent type of nuclear body, contribute to genome organization with global effects on gene expression and RNA splicing fidelity.

    • Qiuyan Wang
    • , Iain A. Sawyer
    •  & Miroslav Dundr
  • Article
    | Open Access

    Leiomodins and Tropomodulins are related, but have different functions; actin filament nucleation and pointed end capping, respectively. Here, the authors use structural, biochemical and cellular approaches to show how these different activities have evolved based on a common protein fold.

    • Malgorzata Boczkowska
    • , Grzegorz Rebowski
    •  & Roberto Dominguez
  • Article
    | Open Access

    Endocytosis typically directs proteins on a recycling route back to the plasma membrane, transport to the Golgi apparatus or delivery to the lysosome. Here Chaumet et al.describe a population of vesicles that can fuse directly with the outer nuclear membrane and deliver cargo into the nuclear envelope, where it can be translocated into the nucleoplasm.

    • Alexandre Chaumet
    • , Graham D. Wright
    •  & Frederic Bard
  • Article
    | Open Access

    The mechanical properties of the metazoan nucleus can be influenced by the nuclear lamina. Here, Schreiner et al.show that untethering chromatin from the inner nuclear membrane results in highly deformable, softer nuclei, revealing an important role for chromatin in modulating nuclear mechanics.

    • Sarah M. Schreiner
    • , Peter K. Koo
    •  & Megan C. King
  • Article |

    The protein kinase Rio1 is known to promote 40S ribosome formation in the cytoplasm. Using budding yeast, the authors here show that Rio1 also acts in the nucleus, downregulates rDNA transcription by Pol I, and activates the processing of its transcripts to ensure rDNA stability and segregation.

    • Maria G. Iacovella
    • , Cristina Golfieri
    •  & Peter De Wulf
  • Article
    | Open Access

    Meiotic maturation of oocytes and early development of mammalian embryos is largely dependent on the translation of mRNAs stored in the oocyte. Here the authors uncover a population of mRNA retained in the oocyte nucleus whose translation is spatially and temporally regulated by the mTOR–eIF4F pathway during meiosis.

    • Andrej Susor
    • , Denisa Jansova
    •  & Michal Kubelka