Cell polarity

  • Article
    | Open Access

    PAK4 is a kinase involved in cell-cell junctions, though the identify of the  local protein network involving PAK4 is unclear. Here, the authors performed proximity proteomic analysis on mammalian PAK4 and find  that PAK4 is associated with Afadin-dependent junctions, and report putative PAK4 phosphorylation substrates at this site.

    • Yohendran Baskaran
    • , Felicia Pei-Ling Tay
    •  & Edward Manser
  • Article
    | Open Access

    Epithelial cells that organise into structures that contain a lumen are polarised. Here, the authors show that the short intracellular domain of transmembrane protein CD13 is required to capture endosomes at the apical site and is required for the polarisation of cells.

    • Li-Ting Wang
    • , Abira Rajah
    •  & Luke McCaffrey
  • Article
    | Open Access

    Early stages of embryogenesis are known to depend on subcellular localization and transport of maternal mRNA, but systematic analyses have been hindered by a lack of methods for tracking of RNA. Here the authors combine spatially-resolved transcriptomics and single-cell RNA labeling to perform a spatio-temporal analysis of the transcriptome during early zebrafish development, revealing insights into this process.

    • Karoline Holler
    • , Anika Neuschulz
    •  & Jan Philipp Junker
  • Article
    | Open Access

    Sensory hair cells develop an asymmetric architecture to restrict stimulus detection to a single axis. Here the authors identify GPR156 as directing a 180-degree reversal in hair cell orientation through Gαi, downstream of EMX2 in the mouse inner ear and zebrafish lateral line.

    • Katie S. Kindt
    • , Anil Akturk
    •  & Basile Tarchini
  • Article
    | Open Access

    Establishing protein gradients for asymmetric cell division is fundamental across all kingdoms of life. Here the authors construct asymmetric cell division in E. coli by localizing the expression of RNA polymerase using an orthogonal unipolar scaffold, and restricting diffusion of its products.

    • Da-Wei Lin
    • , Yang Liu
    •  & Hsiao-Chun Huang
  • Article
    | Open Access

    Contact stimulation of migration drives tissue morphogenesis. Here the authors report that filopodia-based contact-dependent asymmetry of cell–matrix adhesion drives directional movement, whereas contractile actin cables contribute to the integrity of the migrating cell cluster in the myotubes of Drosophila developing testes.

    • Maik C. Bischoff
    • , Sebastian Lieb
    •  & Sven Bogdan
  • Article
    | Open Access

    Cilia originate from a basal body and basal foot, but the precise molecular mechanisms of basal foot biogenesis are unclear. Here, the authors show that ANKS1A interacts with FOP to transform the subdistal appendages from an unpolarized structure to a polarized structure with a basal foot.

    • Hyunchul Ryu
    • , Haeryung Lee
    •  & Soochul Park
  • Article
    | Open Access

    The I-BAR protein IRSp53 senses membrane curvature but its physiological role is unclear. Here, the authors show that during early lumen morphogenesis, IRSp53 controls the shape of the apical plasma membrane and polarized trafficking and ensures the correct epithelial tubular architecture and if deleted, affects renal tubules morphogenesis in various organisms.

    • Sara Bisi
    • , Stefano Marchesi
    •  & Andrea Disanza
  • Article
    | Open Access

    Budding yeast cell polarization is known to self-assemble, but it is still not clear what controls the size of the resulting septin ring. Here the authors show that the septin ring diameter is set by cell volume, ensuring that larger cells have larger rings.

    • I. V. Kukhtevich
    • , N. Lohrberg
    •  & K. M. Schmoller
  • Article
    | Open Access

    The evolutionarily conserved complex, the Par proteins, regulates cell polarity. Here, the authors show that in Drosophila neuroblasts, the Par complex exhibits liquid–liquid phase separation dependent on the cell cycle.

    • Ziheng Liu
    • , Ying Yang
    •  & Wenyu Wen
  • 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

    To model hepatocyte function accurately in vitro, it is necessary to generate and maintain a polarized epithelium. Here, the authors describe a protocol to generate polarized human pluripotent stem cell-derived hepatocyte-like cells (HLCs) to model enteric virus production and drug secretion in vitro.

    • Viet Loan Dao Thi
    • , Xianfang Wu
    •  & Charles M. Rice
  • Article
    | Open Access

    While biallelic mutations of the SLC26A4 gene cause non-syndromic hearing loss with enlarged vestibular aqueducts or Pendred syndrome, a considerable number of patients carry mono-allelic mutations. Here the authors identify EPHA2 as another causative gene of Pendred syndrome with SLC26A4.

    • Mengnan Li
    • , Shin-ya Nishio
    •  & Masanori Nakayama
  • Article
    | Open Access

    De novo lumen formation during vertebrate left–right organizer development is required for body axis establishment. Here the authors utilize zebrafish to demonstrate that the position and cleavage of the cytokinetic bridge in dividing left-right organizer cells dictates tissue morphogenesis.

    • L. I. Rathbun
    • , E. G. Colicino
    •  & H. Hehnly
  • Article
    | Open Access

    How receptor localization affects morphogen gradient formation during embryonic development is unclear. Here, the authors study the relationship between the BMP gradient, receptor localization, and compartmentalized geometry in the early mouse embryo, using experimental data and computational simulation.

    • Zhechun Zhang
    • , Steven Zwick
    •  & Sharad Ramanathan
  • Article
    | Open Access

    Planar cell polarity (PCP) regulates hair cell orientation in the zebrafish lateral line. Here, the authors show that mutating Wnt pathway genes (wnt11f1, fzd7a/b, and gpc4) causes concentric hair cell patterns not regulated by PCP, thus showing PCP/Wnt pathway genes have different consequences on hair cell orientation.

    • Joaquin Navajas Acedo
    • , Matthew G. Voas
    •  & Tatjana Piotrowski
  • Article
    | Open Access

    Asymmetric subcellular mRNA distribution is important for local translation of neuronal mRNAs. Here the authors employed MS2 live-cell imaging and showed that the reporter mRNA containing the 3’ UTR of Rgs4 shows an anterograde transport bias, dependent on neuronal activity and the protein Staufen2, and mediates sustained mRNA recruitment to synapses.

    • Karl E. Bauer
    • , Inmaculada Segura
    •  & Michael A. Kiebler
  • Article
    | Open Access

    Angiogenesis is driven by the directed migration of tip endothelial cells towards hypoxic tissues. Here, Kim et al. show that the generation of reactive oxygen species in endothelial cells upon hypoxia activates MST1, which subsequently promotes the nuclear translocation of FOXO1, and thus activates a pro-migratory transcriptional programme in endothelial tip cells.

    • Yoo Hyung Kim
    • , Jeongwoon Choi
    •  & Gou Young Koh
  • Article
    | Open Access

    Cells divide within a given size range and can scale across differing cell sizes but mechanisms and function remain unclear. Here the authors show, despite the current dogma of fission yeast maintaining constant width, some fission yeast can scale their width and length, impacting the positioning of the cell division site.

    • Ying Gu
    •  & Snezhana Oliferenko
  • Article
    | Open Access

    The cell polarity regulator aPKC is associated with cell proliferation but the precise mechanism are unknown. Here, the authors find that aPKC lambda phosphorylates the FoxO1 transcription factor, a gatekeeper of endothelial growth, during both angiogenesis and angiosarcomas.

    • Meghan Riddell
    • , Akiko Nakayama
    •  & Masanori Nakayama
  • Article
    | Open Access

    During de novo establishment of apical-basal polarity, a basolateral membrane must be converted into an apical delivery zone. Here, the authors use MDCK 3D cysts to uncover that the phospholipid PI(3,4)P2 is an apical membrane determinant.

    • Álvaro Román-Fernández
    • , Julie Roignot
    •  & David M. Bryant
  • Article
    | Open Access

    Tracheal development arises due to tube morphogenesis but how this is regulated is unclear. Here, the authors identify polarization of smooth muscle progenitors as controlling murine tracheal development, activating noncanonical Wnt signaling followed by subepithelial morphogenesis and ring cartilage development.

    • Keishi Kishimoto
    • , Masaru Tamura
    •  & Mitsuru Morimoto
  • 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

    Anteroposterior axis extension during gastrulation is dynamically coordinated, but how this is regulated at a molecular level is unclear. Here, the authors show in zebrafish that the chromatin factor Gon4l, encoded by ugly duckling, coordinates axis extension by modulating EpCAM and Integrinα3b expression.

    • Margot L. K. Williams
    • , Atsushi Sawada
    •  & Lilianna Solnica-Krezel
  • Article
    | Open Access

    Polarisation of metastasising cancer cells in circulation has not been investigated before. Here the authors identify single cell polarity as a distinct polarisation state of single cells in liquid phase, and show that perturbing single cell polarity affects attachment, adhesion, transmigration and metastasis in vitro and in vivo.

    • Anna Lorentzen
    • , Paul F. Becker
    •  & Mathias Heikenwalder
  • Article
    | Open Access

    Polarized localization of Numb and Pon in Drosophila neuroblasts (NBs) enables their unequal segregation during asymmetric cell divisions. Here, the authors demonstrate liquid-liquid phase separation of Pon and Numb in NBs mediated by multivalent intermolecular interactions is required for their basal condensation.

    • Zelin Shan
    • , Yuting Tu
    •  & Wenyu Wen
  • Article
    | Open Access

    Tip-growing cells can find their growing path toward the source of attractive signals. Here, using experimental data and mathematical modeling, Luo et al. demonstrate that tip-localized exocytosis can integrate guidance cues with Rho GTPase signaling to control cell wall mechanics and direct tip growth in Arabidopsis pollen tubes.

    • Nan Luo
    • , An Yan
    •  & Zhenbiao Yang
  • Article
    | Open Access

    Chemotaxis during differentiation of Dictyostelium discoideum requires four signalling pathways to maintain directional cell migration, but it is unclear how they are coordinated. Here the authors show that the RNA-binding protein Pumilio localizes mRNAs and proteins of these pathways and actin at the cell front during dynamic cell migration.

    • Manuel Hotz
    •  & W. James Nelson
  • Article
    | Open Access

    The molecular trigger that establishes cell polarity in the mammalian embryo is unclear. Here, the authors show that de novo polarisation of the mouse embryo at the 8-cell stage is directed by Phospholipase C and Protein kinase C and occurs in two phases: polarisation of actomyosin followed by the Par complex.

    • Meng Zhu
    • , Chuen Yan Leung
    •  & Magdalena Zernicka-Goetz
  • Article
    | Open Access

    Platelets derive from large precursor cells (megakaryocytes) in the bone marrow. Düttinget al. show that megakaryocyte polarization and platelet biogenesis in the bone-marrow sinusoids are directed by adhesion receptor GPIb signalling and resulting balanced antagonism between RhoA (stop-signal) and Cdc42 (go-signal).

    • Sebastian Dütting
    • , Frederique Gaits-Iacovoni
    •  & Bernhard Nieswandt
  • Article
    | Open Access

    Polarized epithelial cells must correctly position a wide range of subcellular structures. Here the authors demonstrate an apicobasal gradient of Rac GTPase activity, which is maintained by polarity proteins inDrosophilaepithelial sheets, and is required to maintain actin-dependent protrusion form and position.

    • Africa Couto
    • , Natalie Ann Mack
    •  & Marios Georgiou
  • Article
    | Open Access

    The exocyst delivers basolateral proteins from the secretory pathway to the plasma membrane of epithelial cells close to tight junctions. Here the authors show that Par3 acts as a docking site for the exocyst to regulate polarized delivery of basolateral proteins and this is essential to prevent apoptosis and promote mammary cell survival.

    • Syed Mukhtar Ahmed
    •  & Ian G. Macara
  • Article
    | Open Access

    The transfer of ubiquitin (UB) to cellular targets is mediated sequentially by three groups of enzymes, UB activating enzyme (E1), UB conjugating enzyme (E2) and UB ligase (E3). Here the authors provide evidence that the two mammalian E1 enzymes, Uba1 and Uba6, exert biologically distinct functions.

    • Xianpeng Liu
    • , Bo Zhao
    •  & Hiroaki Kiyokawa
  • Article
    | Open Access

    Polarisation of epithelial cells causes lumen formation, which is mediated by apical membrane initiation site (AMIS) and FIP5, but how this is regulated is unclear. Here, the authors identify cingulin as a FIP-5 interacting protein, recruiting the Rac1-WAVE/Scar complex to the AMIS and branched actin formation.

    • Anthony J. Mangan
    • , Daniel V. Sietsema
    •  & Rytis Prekeris
  • Article
    | Open Access

    GRIP1 cooperates with the glucocorticoid receptor to repress inflammatory genes. Here the authors show that GRIP1 also controls macrophage polarization, by promoting KLF4-driven activation in response to IL-4, and that mice lacking GRIP1 in macrophages develop severe metabolic dysfunction on a high-fat diet.

    • Maddalena Coppo
    • , Yurii Chinenov
    •  & Inez Rogatsky
  • 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