Nuclear envelope

  • Article
    | Open Access

    Mechanical strength of in situ assembled nuclear lamin filaments arranged in a 3D meshwork is unclear. Here, using mechanical, structural and simulation tools, the authors report the hierarchical organization of the lamin meshwork that imparts strength and toughness to lamin filaments at par with silk and Kevlar®

    • K. Tanuj Sapra
    • , Zhao Qin
    •  & Ohad Medalia
  • Article
    | Open Access

    Mandibuloacral dysplasias (MADs) are rare progeroid syndromes characterized by nuclear morphological and functional abnormalities. Here the authors report that loss of mitochondrial membrane protein MTX2 causes a progeroid MAD sharing clinical features with lamin-associated progeroid syndromes.

    • Sahar Elouej
    • , Karim Harhouri
    •  & Annachiara De Sandre-Giovannoli
  • Article
    | Open Access

    mRNAs export from the nucleus is thought to be regulated in part by three nucleoporins that comprise the nuclear basket, but whether and how distinct basket nucleoporins interact with the RNA export machinery is unclear. Here, the authors use rapid auxin-mediated degradation of basket nucleoporins Nup153, Nup50, and Tpr, and see that Tpr interacts with the TREX-2 mRNA export complex.

    • Vasilisa Aksenova
    • , Alexandra Smith
    •  & Mary Dasso
  • Article
    | Open Access

    During cell migration, cells are polarized with distinct front vs. rear regions but whether and how polarity is transmitted to the nucleus is unclear. Here the authors show that frontally-biased endoplasmic reticulum and the nuclear membrane protein Emerin contribute to front-rear nuclear cell polarity.

    • Paulina Nastały
    • , Divya Purushothaman
    •  & Paolo Maiuri
  • Article
    | Open Access

    Torsins are unusual AAA + ATPases of unknown function that reside in the endoplasmic reticulum of all animals. Here the authors report that TorsinA forms tubular helical filaments with an unusual periodicity and that filamentous TorsinA directly interacts with membranes to form tubular protrusions.

    • F. Esra Demircioglu
    • , Weili Zheng
    •  & Thomas U. Schwartz
  • Article
    | Open Access

    Rif1 is involved in different processes such as telomere homeostasis, DNA replication timing, and DNA double strand break (DSB) repair pathway choice. Here, the authors reveal that Rif1 S-acylation facilitates the accumulation of Rif1 at DSBs, attenuation of DNA end-resection, and DSB repair by non-homologous end-joining.

    • Gabriele A. Fontana
    • , Daniel Hess
    •  & Ulrich Rass
  • Article
    | Open Access

    Nuclear size scales with cell size, but the underlying mechanisms are unclear. Here, the authors report in fission yeast that the inner nuclear membrane protein Lem2 and the ER membrane protein Lnp1 are barriers to membrane flow and propose that they maintain nuclear size in proportion to cell membrane content.

    • Kazunori Kume
    • , Helena Cantwell
    •  & Paul Nurse
  • Article
    | Open Access

    Nuclear envelopathies are a group of diseases caused by genetic mutations in essential nuclear envelope genes. Here, the authors report a nuclear envelopathy with a homozygous nonsense variant in TOR1AIP1 which leads to changes in the nuclear morphology including large nuclear-spanning channels in patients’ fibroblasts.

    • Boris Fichtman
    • , Fadia Zagairy
    •  & Ronen Spiegel
  • 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

    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

    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

    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