Cell biology

  • Article
    | Open Access

    The cellular identity and function of the pancreatic polypeptide (Ppy)-producing γ-cells are incompletely understood. Here the authors show that these cells are heterogeneous and display adaptive plasticity to engage in insulin production following β-cell injury, but loss of the Ppy gene or γ-cells in mice does not affect weight or glycemia under basal conditions.

    • Marta Perez-Frances
    • , Léon van Gurp
    •  & Pedro L. Herrera
  • Article
    | Open Access

    Uncontrolled activation of fibroblasts contributes to tissue fibrosis and organ dysfunction. Here the authors demonstrate that the epigenetic control of autophagy is disturbed by a TGFβ-dependent downregulation of MYST1 in systemic sclerosis patients. Restoration of the epigenetic control of autophagy reduces fibroblast activation and ameliorates fibrotic tissue remodeling.

    • Ariella Zehender
    • , Yi-Nan Li
    •  & Jörg H. W. Distler
  • Article
    | Open Access

    Necroptosis, a form of cell death, occurs in acute renal injury. Here, the authors show that ferroptosis—a form of cell death dependent on iron - also occurs during acute kidney injury, and show that an inhibitor of ferroptosis can improve survival in a mouse model of acute kidney damage.

    • Wulf Tonnus
    • , Claudia Meyer
    •  & Andreas Linkermann
  • Article
    | Open Access

    Extracellular vesicles (EVs) play a role in intercellular communication, however the precise biogenesis of different populations of EVs are not clear. Here, the authors follow the intracellular trafficking of two proteins before their secretion in EVs and report the biogenesis and protein markers of EV subtypes: ectosomes budding from the plasma membrane as well as exosomes from late endosomes.

    • Mathilde Mathieu
    • , Nathalie Névo
    •  & Clotilde Théry
  • Article
    | Open Access

    Acute pancreatitis is a serious inflammatory disease, which is more severe in diabetic mice. Here the authors use mice lacking pancreatic acinar cell insulin receptors to show that this may be because insulin preserves glycolytic energy supply in acinar cell during pancreatitis, which prevents cytotoxic calcium overload and cell death.

    • Jason I. E. Bruce
    • , Rosa Sánchez-Alvarez
    •  & John A. Williams
  • Article
    | Open Access

    HAP2 is essential for gamete fusion during fertilization and is conserved among eukaryotes. Here the authors show that species-specific adhesion between Chlamydomonas plus and minus gametes initiates HAP2 to undergo a fusogenic conformational change into homotrimers via a molecular mechanism akin to that of enveloped viruses.

    • Jun Zhang
    • , Jennifer F. Pinello
    •  & William J. Snell
  • Article
    | Open Access

    Memory T cells are particularly reliant on fatty acid oxidation as a source of energy. Here the authors show this reliance is controlled by AMPK sensing of glucose deprivation that triggers SENP1-Sirt3 signalling, driving fatty acid oxidation and memory differentiation in T cells via deacetylation of YME1L1 to induce mitochondrial fusion.

    • Jianli He
    • , Xun Shangguan
    •  & Jinke Cheng
  • Article
    | Open Access

    Glucocorticoids (GC) are reported to block cancer cell proliferation, but the mode of action is unclear. Here the authors show that glucocorticoid receptor activation induces cancer cell dormancy in lung cancer by regulating CDKN1C expression through a distal enhancer, and these dormant cells are addicted to IGF-1R signalling pathway.

    • Stefan Prekovic
    • , Karianne Schuurman
    •  & Wilbert Zwart
  • Article
    | Open Access

    The small molecule DNMDP acts as a velcrin by inducing complex formation between phosphodiesterase PDE3A and SLFN12, which kills cancer cells that express sufficient levels of both proteins. Here, the authors present the cryo-EM structure of the DNMDP-stabilized PDE3A-SLFN12 complex and show that SLFN12 is an RNase. PDE3A binding increases SLFN12 RNase activity, and SLFN12 RNase activity is required for DNMDP-mediated cancer cell killing.

    • Colin W. Garvie
    • , Xiaoyun Wu
    •  & Heidi Greulich
  • Article
    | Open Access

    Rare earth elements are widely used in agriculture to promote plant growth. Here the authors show that aerial application of a rare earth element to the leaves triggers a graft-transmissible, RbohD- and jasmonic acid-dependent systemic signal that triggers endocytosis and mineral nutrient uptake in roots.

    • Mengzhu Cheng
    • , Lihong Wang
    •  & Zhenbiao Yang
  • Article
    | Open Access

    Mutations in ryanodine receptor 1 (RyR1), a Ca2+ release channel in skeletal muscle, cause malignant hyperthermia (MH) and are involved in heat stroke. Here, the authors show that an oxolinic acid-derivative RyR1 inhibitor effectively prevents and treats MH and heat stroke in various MH mouse models.

    • Toshiko Yamazawa
    • , Takuya Kobayashi
    •  & Takashi Murayama
  • Article
    | Open Access

    Tuberous sclerosis complex (TSC) is a multiorgan disease that can lead to hyperactive mTORC1 due to deficient TSC1 or TSC2 protein function. Here, the authors find that despite high mTORC1 activity, TFEB localizes to the nucleus and drives lysosomal gene expression via a non-canonical Rag-dependent mechanism.

    • Nicola Alesi
    • , Elie W. Akl
    •  & Elizabeth P. Henske
  • Article
    | Open Access

    Accurate regulation of protein concentrations according to changes in cell volume that accompany growth and changes in biosynthetic capacity is an important component of cellular homeostasis. Here, using the model organism S. cerevisiae, the authors show how histone production is quantitatively coupled to genome content through the intrinsic properties of histone promoters.

    • Kora-Lee Claude
    • , Daniela Bureik
    •  & Kurt M. Schmoller
  • Article
    | Open Access

    Extracellular matrix protein 1 (ECM1) has been associated with cancer but the underlying molecular mechanisms are not clear. Here, the authors show that while ECM1b isoform is a tumour suppressor, the secreted isoform ECM1a promotes tumourigenesis and chemoresistance through increasing stemness and alternative mRNA splicing in ovarian cancer.

    • Huijing Yin
    • , Jingshu Wang
    •  & Gong Yang
  • Article
    | Open Access

    Cells can modify their environment by depositing biochemical signals or mechanically remodelling the extracellular matrix; the impact of such self-induced environmental perturbations on cell trajectories at various scales remains unexplored. Here authors show that motile cells leave long-lived physicochemical footprints along their way, which determine their future path.

    • Joseph d’Alessandro
    • , Alex Barbier--Chebbah
    •  & Benoît Ladoux
  • Article
    | Open Access

    Non-centrosomal microtubules provide essential functions in many cells, but the mechanisms of their formation are poorly understood. Here, the authors show that during tube formation of the Drosophila salivary glands, microtubules are released from a single active centrosome via katanin, triggering recruitment of Patronin, and leading to formation of a non-centrosomal network key to the tube invagination process.

    • Ghislain Gillard
    • , Gemma Girdler
    •  & Katja Röper
  • Article
    | Open Access

    Sarcomeres, the building blocks of striated muscles, comprise ordered actomyosin arrays involved in force production. Here, the authors visualize sarcomere organization in neonatal cardiomyocytes with in situ cryo-electron tomography, revealing a reduced order of the thin filaments, their sliding and functional states enabling contraction.

    • Laura Burbaum
    • , Jonathan Schneider
    •  & Marion Jasnin
  • Article
    | Open Access

    Emerging evidence suggests that exit from pluripotency is a regulated, rather than passive process. Here the authors identify a requirement for SS18-mediated Brg/Brahma-associated factors (BAF) chromatin remodeling complex assembly during exit from pluripotency, and that SS18 promotes BAF assembly through liquidliquid phase separation.

    • Junqi Kuang
    • , Ziwei Zhai
    •  & Duanqing Pei
  • Article
    | Open Access

    Activation of c-MET receptor tyrosine kinase involves hepatocyte growth factor (HGF) and glycosaminoglycans, but the molecular mechanism is still under debate. Here, the authors present cryoEM structures of c-MET bound to two HGF splice variants and heparin, revealing the structural basis for c-MET activation.

    • Emiko Uchikawa
    • , Zhiming Chen
    •  & Xiao-chen Bai
  • Article
    | Open Access

    Bacterial pathogens can subvert host cell processes through secreted proteins but the precise mechanisms and repertoire of proteins remains unclear. Here the authors report that a bacterial effector protein of Xanthomonas campestris, XopR, undergoes liquid-liquid phase separation to hijack the host cell actin cytoskeleton.

    • He Sun
    • , Xinlu Zhu
    •  & Yansong Miao
  • Article
    | Open Access

    Schinzel-Giedion syndrome (SGS) is a fatal developmental syndrome characterized by severe intellectual and physical deficits due, at least in part, to early neurodegeneration. Here the authors introduce a human SGS model that displays disease-relevant phenotypes to demonstrate that neuronal death in SGS originates from developmental alterations mainly in safeguarding cell identity and homeostasis.

    • Federica Banfi
    • , Alicia Rubio
    •  & Alessandro Sessa
  • Article
    | Open Access

    The permeability barrier of nuclear pore complexes blocks passage of inert macromolecules but allows rapid, receptor-mediated, and RanGTPase-driven transport of cargoes up to ribosome size. The authors now show that such a barrier can be faithfully recapitulated by an ultimately simplified FG phase assembled solely from a tandemly repeated 12mer GLFG peptide.

    • Sheung Chun Ng
    • , Thomas Güttler
    •  & Dirk Görlich
  • Article
    | Open Access

    Most mutant p53 heterozygous tumours undergo loss of the remaining wildtype (WT) p53 allele which leads to stabilization of the mutant p53 protein. Here, the authors show in an autochthonous colorectal cancer model that the WT p53 allele retains partial activity and suppresses the heat shock factor 1 (HSF1)- chaperone axis to prevent mutant p53 stabilisation and mutant p53 gain-of-function activities, thereby creating selective pressure for p53 loss-of-heterozygosity.

    • Tamara Isermann
    • , Özge Çiçek Şener
    •  & Ramona Schulz-Heddergott
  • Article
    | Open Access

    Iron is essential during pregnancy for embryo and placental development and maternal health. However, in this study using mouse models, the authors demonstrate that excess maternal iron causes adverse embryo outcomes in pregnancies with underlying systemic inflammation.

    • Allison L. Fisher
    • , Veena Sangkhae
    •  & Elizabeta Nemeth
  • Article
    | Open Access

    The authors show in Nematostella that the more orally expressed β-catenin targets repress the more aborally expressed β-catenin targets, thus patterning the oral-aboral axis. This likely represents the common mechanism of β-catenin-dependent axial patterning shared by Cnidaria and Bilateria.

    • Tatiana Lebedeva
    • , Andrew J. Aman
    •  & Grigory Genikhovich
  • Article
    | Open Access

    Recognition of laminin by integrin receptors mediates epithelial cell adhesion to basement membrane. Here, the structures of the α6β1 integrin alone and in complex with three-chain laminin-511 fragment reveal the laminin-integrin interface in molecular detail.

    • Takao Arimori
    • , Naoyuki Miyazaki
    •  & Junichi Takagi
  • Article
    | Open Access

    The molecular mechanisms underlying cancer cell radioresistance need to be elucidated. In this study, the authors show that the microRNA biogenesis factor DGCR8 is stabilized by USP51 and ATM upon irradiation and by consequence it promotes the repair of DNA double-strand breaks and radioresistance by recruiting RNF168 to sites of damage.

    • Qinglei Hang
    • , Liyong Zeng
    •  & Li Ma
  • Article
    | Open Access

    Type-III secretion systems (T3SSs) are capable of translocating proteins with high speed while maintaining the membrane barrier for small molecules. Here, a structure-function analysis of the T3SS pore complex elucidates the precise mechanisms enabling the gating and the conformational changes required for protein substrate secretion.

    • Svenja Hüsing
    • , Manuel Halte
    •  & Thibaud T. Renault
  • Article
    | Open Access

    MYCN is frequently amplified in neuroblastomas. Here, the authors show that MYCN disrupts the molecular clock by downregulating clock activator RORα and that the reactivation of RORα restores BMAL1 activity, and inhibits lipid metabolism and neuroblastoma growth

    • Myrthala Moreno-Smith
    • , Giorgio Milazzo
    •  & Eveline Barbieri
  • Article
    | Open Access

    Beneficial and detrimental effects have been ascribed to the different Thrombospondin (Thbs) proteins in the adult mammalian heart. Here, the authors show that Thbs1-mediated activation of PERK-eIF2α-ATF4-induced autophagy regulates adult cardiomyocyte size in the stressed heart.

    • Davy Vanhoutte
    • , Tobias G. Schips
    •  & Jeffery D. Molkentin
  • Article
    | Open Access

    It is currently thought that the thylakoid proteins PGRL1 and PGR5 form a complex to mediate cyclic electron flow (CEF) around photosystem I. Here the authors show that CEF can in fact be mediated by PGR5 alone and that PGRL1 and the homologous PGRL2 modify the process by modulating PGR5 activity and stability.

    • Thilo Rühle
    • , Marcel Dann
    •  & Dario Leister
  • Article
    | Open Access

    Age-related macular degeneration (AMD) has been connected to deficits in autophagy. Here, the authors demonstrate, in mice and dry-AMD patient samples, that calcium and integrin binding protein 2 (CIB2) regulates Rheb-mTORC1 signaling axis, and subsequently autophagy.

    • Saumil Sethna
    • , Patrick A. Scott
    •  & Zubair M. Ahmed
  • Article
    | Open Access

    Human Treg cells are central to immune tolerance, yet their heterogeneity and differentiation remain incompletely understood. Here the authors perform single-cell RNA and T cell receptor sequencing to resolve Treg cells from healthy individuals and patients with or without acute graft-versus-host disease revealing Treg complexity in health and disease.

    • Yuechen Luo
    • , Changlu Xu
    •  & Xiaoming Feng
  • Article
    | Open Access

    CD45 limits T cell activation, so its exclusion from the T cell immunological synapse is thought to occur as a means to enable TCR signalling. Here the authors use a variety of cellular imaging methods to show that CD45 is indeed excluded from the tips of the T cell microvilli and that this occurs prior to contact with antigen, indicating this exclusion is one of the initiating factors for antigen presentation and T cell activation.

    • Yunmin Jung
    • , Lai Wen
    •  & Klaus Ley
  • Article
    | Open Access

    Single-stranded DNA during DNA replication and repair in S/G2 needs protection by replication protein A (RPA). Here the authors reveal that RPA also shields inherited single-stranded DNA in G1, representing replication remnants from the previous cell cycle, to allow for post-mitotic DNA synthesis.

    • Aleksandra Lezaja
    • , Andreas Panagopoulos
    •  & Matthias Altmeyer
  • Article
    | Open Access

    Classically, myogenic precursor cells derive from somites, and connective tissues derive from lateral plate mesoderm (LPM). Here the authors identify LPM derived fibroblasts that turn on a myogenic program and fuse to muscle fibers at muscle-tendon junctions, introducing fibroblast transcripts into myofibers.

    • Wesal Yaseen
    • , Ortal Kraft-Sheleg
    •  & Peleg Hasson
  • Article
    | Open Access

    Centriole biogenesis begins with self-assembly of SAS-6 proteins into 9-fold symmetrical ring polymers, which then stack into a cartwheel that scaffolds organelle formation. Here, the authors develop monobodies against Chlamydomonas reinhardtii SAS-6 and use X-ray crystallography, atomic force microscopy and cryo-electron microscopy to reveal insights into ring assembly and stacking.

    • Georgios N. Hatzopoulos
    • , Tim Kükenshöner
    •  & Pierre Gönczy