Planar cell polarity induces local microtubule bundling for coordinated ciliary beating

Multiciliated cells (MCCs) in tracheas generate mucociliary clearance through coordinated ciliary beating. Apical microtubules (MTs) play a crucial role in this process by organizing the planar cell polarity (PCP)–dependent orientation of ciliary basal bodies (BBs), for which the underlying molecular basis remains elusive. Herein, we found that the deficiency of Daple, a dishevelled-associating protein, in tracheal MCCs impaired the planar polarized apical MTs without affecting the core PCP proteins, causing significant defects in the BB orientation at the cell level but not the tissue level. Using live-cell imaging and ultra-high voltage electron microscope tomography, we found that the apical MTs accumulated and were stabilized by side-by-side association with one side of the apical junctional complex, to which Daple was localized. In vitro binding and single-molecule imaging revealed that Daple directly bound to, bundled, and stabilized MTs through its dimerization. These features convey a PCP-related molecular basis for the polarization of apical MTs, which coordinate ciliary beating in tracheal MCCs.

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Continuum Theory for Planar Cell Polarity

10.1101/2021.11.30.468758 ◽

2021 ◽

Author(s):

Mohd. Suhail Rizvi ◽

Divyoj Singh ◽

Mohit Kumar Jolly

Keyword(s):

Cell Membrane ◽

Cell Polarity ◽

Protein Interactions ◽

Planar Cell Polarity ◽

Protein Localization ◽

Continuum Theory ◽

Fruit Fly ◽

Tissue Level ◽

Cellular Protein ◽

Tube Formation

Planar Cell Polarity (PCP), characterized by asymmetric localization of proteins at the cell membrane within the epithelial plane, plays essential roles in embryonic development and physiological functions. The significance of PCP can be appreciated by the outcomes of PCP failure in the form of defects in neural tube formation, tracheal malfunctions, organ shape misregulation, hair follicle misalignment etc. Extensive experimental works on PCP in fruit fly Drosophila melanogaster have classified the proteins involved in PCP into two modules: 'core' module, acting locally by inter-cellular protein interactions, and, 'global' module, responsible for the alignment of cell polarities with that of the tissue axis. Despite the involvement of different molecular players, the asymmetric localization of the proteins of the two modules on cell membrane primarily involve inter-cellular dimer formations. We have developed a continuum model of the localization of PCP proteins on the cell membrane and its regulation via intra- and inter-cellular protein-protein interactions. We have identified the conditions for the asymmetric protein localization, or PCP establishment, for uniform and graded protein expression levels in the tissue. We have found that in the absence of any tissue level expression gradient the polarized state of the tissue is not stable against finite length perturbations which is also a property of the active polar matter. However, in the presence of tissue level expression gradients of proteins the polarized state remains stable. We have also looked at the influence of the loss of PCP proteins from a select regions of the tissue on the polarization of the cells outside of that region. This continuum theory of the planar cell polarity can be coupled with the active matter hydrodynamics to study the cell flows and their regulation by genetic machinery.

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Par3 is essential for the establishment of planar cell polarity of inner ear hair cells

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1816333116 ◽

2019 ◽

Vol 116 (11) ◽

pp. 4999-5008 ◽

Cited By ~ 11

Author(s):

Andre Landin Malt ◽

Zachary Dailey ◽

Julia Holbrook-Rasmussen ◽

Yuqiong Zheng ◽

Arielle Hogan ◽

...

Keyword(s):

Hair Cell ◽

Inner Ear ◽

Cell Polarity ◽

Hair Cells ◽

Planar Cell Polarity ◽

Tissue Level ◽

Hair Bundle ◽

Nucleotide Exchange ◽

Genetic Mosaic ◽

Pcp Signaling

In the inner ear sensory epithelia, stereociliary hair bundles atop sensory hair cells are mechanosensory apparatus with planar polarized structure and orientation. This is established during development by the concerted action of tissue-level, intercellular planar cell polarity (PCP) signaling and a hair cell-intrinsic, microtubule-mediated machinery. However, how various polarity signals are integrated during hair bundle morphogenesis is poorly understood. Here, we show that the conserved cell polarity protein Par3 is essential for planar polarization of hair cells. Par3 deletion in the inner ear disrupted cochlear outgrowth, hair bundle orientation, kinocilium positioning, and basal body planar polarity, accompanied by defects in the organization and cortical attachment of hair cell microtubules. Genetic mosaic analysis revealed that Par3 functions both cell-autonomously and cell-nonautonomously to regulate kinocilium positioning and hair bundle orientation. At the tissue level, intercellular PCP signaling regulates the asymmetric localization of Par3, which in turn maintains the asymmetric localization of the core PCP protein Vangl2. Mechanistically, Par3 interacts with and regulates the localization of Tiam1 and Trio, which are guanine nucleotide exchange factors (GEFs) for Rac, thereby stimulating Rac-Pak signaling. Finally, constitutively active Rac1 rescued the PCP defects in Par3-deficient cochleae. Thus, a Par3–GEF–Rac axis mediates both tissue-level and hair cell-intrinsic PCP signaling.

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Planar cell polarity signaling, cilia and polarized ciliary beating

Current Opinion in Cell Biology ◽

10.1016/j.ceb.2010.07.011 ◽

2010 ◽

Vol 22 (5) ◽

pp. 597-604 ◽

Cited By ~ 106

Author(s):

John B Wallingford

Keyword(s):

Cell Polarity ◽

Planar Cell Polarity ◽

Ciliary Beating

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Thymosin β4 is essential for adherens junction stability and epidermal planar cell polarity

Development ◽

10.1242/dev.193425 ◽

2020 ◽

Vol 147 (23) ◽

pp. dev193425

Author(s):

Krishnanand Padmanabhan ◽

Hanna Grobe ◽

Jonathan Cohen ◽

Arad Soffer ◽

Adnan Mahly ◽

...

Keyword(s):

Cell Adhesion ◽

Cell Polarity ◽

Actin Polymerization ◽

Planar Cell Polarity ◽

Adherens Junction ◽

Actin Binding ◽

Thymosin Β4 ◽

Eyelid Closure

ABSTRACTPlanar cell polarity (PCP) is essential for tissue morphogenesis and homeostasis; however, the mechanisms that orchestrate the cell shape and packing dynamics required to establish PCP are poorly understood. Here, we identified a major role for the globular (G)-actin-binding protein thymosin-β4 (TMSB4X) in PCP establishment and cell adhesion in the developing epidermis. Depletion of Tmsb4x in mouse embryos hindered eyelid closure and hair-follicle angling owing to PCP defects. Tmsb4x depletion did not preclude epidermal cell adhesion in vivo or in vitro; however, it resulted in abnormal structural organization and stability of adherens junction (AJ) due to defects in filamentous (F)-actin and G-actin distribution. In cultured keratinocytes, TMSB4X depletion increased the perijunctional G/F-actin ratio and decreased G-actin incorporation into junctional actin networks, but it did not change the overall actin expression level or cellular F-actin content. A pharmacological treatment that increased the G/F-actin ratio and decreased actin polymerization mimicked the effects of Tmsb4x depletion on both AJs and PCP. Our results provide insights into the regulation of the actin pool and its involvement in AJ function and PCP establishment.

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Quantitative proximity proteomics resolves the epithelial apical-lateral border and uncovers a vertebrate marginal zone defined by the polarity protein Pals1

10.1101/710202 ◽

2019 ◽

Author(s):

Benedict Tan ◽

Suat Peng ◽

Sara Sandin ◽

Jayantha Gunaratne ◽

Walter Hunziker ◽

...

Keyword(s):

Cell Polarity ◽

Marginal Zone ◽

Hippo Pathway ◽

Molecular Organization ◽

Junctional Complex ◽

Lateral Border ◽

Spatially Resolved ◽

Apical Junctional Complex ◽

Membrane Compartment ◽

Associated Proteins

AbstractEpithelial apico-basal polarity is established through the asymmetric cortical distribution of the Par, Crumbs and Scribble polarity modules. Apical (Par and Crumbs) and basolateral (Scribble) polarity modules overlap at the apical-lateral border, which, in mammals, is defined by the apical junctional complex (AJC). The AJC is composed of tight junctions (TJ) and adherens junctions (AJ) and plays fundamental roles in epithelial morphogenesis and plasticity. However, the molecular composition and precise sub-junctional organization of the AJC and its associated polarity regulators are still not well defined. Here we used the peroxidase APEX2 for quantitative proximity proteomics (QPP) and electron microscopy (EM) imaging to generate a nanometer-scale spatio-molecular map of the apical-lateral border in fully polarized MDCK-II cells. Using Par3 and Pals1 as surrogates for QPP we present a spatially resolved network of ∼800 junction-associated proteins. The network dissects TJ and AJ components and provides strong evidence that TJ are composed of distinct apical and basal subdomains. Moreover, we find that Pals1 and its binding partners PatJ, Lin7c and Crumbs3 define a hitherto unidentified membrane compartment apical of TJ, which we coin the vertebrate marginal zone (VMZ). The VMZ is physically associated with HOMER scaffolding proteins, regulators of apical exocytosis, and membrane-proximal HIPPO pathway proteins. Taken together our work defines the spatial and molecular organization of the apical-lateral border in fully polarized mammalian epithelial cells, reveals an intriguing molecular and spatial conservation of invertebrate and vertebrate cell polarity protein domains, and provides a comprehensive resource of potentially novel regulators of cell polarity and the mammalian AJC.

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Muscularization of the Mesenchymal Outlet Septum during Cardiac Development

Journal of Cardiovascular Development and Disease ◽

10.3390/jcdd7040051 ◽

2020 ◽

Vol 7 (4) ◽

pp. 51

Author(s):

Maurice J. B. van den Hoff ◽

Andy Wessels

Keyword(s):

Cell Polarity ◽

Essential Role ◽

Planar Cell Polarity ◽

Cardiac Development ◽

In Vitro Models ◽

Outflow Tract ◽

Heart Tube ◽

Tgfβ Signaling ◽

Experimental Approaches

After the formation of the linear heart tube, it becomes divided into right and left components by the process of septation. Relatively late during this process, within the developing outflow tract, the initially mesenchymal outlet septum becomes muscularized as the result of myocardialization. Myocardialization is defined as the process in which existing cardiomyocytes migrate into flanking mesenchyme. Studies using genetically modified mice, as well as experimental approaches using in vitro models, demonstrate that Wnt and TGFβ signaling play an essential role in the regulation of myocardialization. They also show the significance of the interaction between cardiomyocytes, endocardial derived cells, neural crest cells, and the extracellular matrix. Interestingly, Wnt-mediated non-canonical planar cell polarity signaling was found to be a crucial regulator of myocardialization in the outlet septum and Wnt-mediated canonical β-catenin signaling is an essential regulator of the expansion of mesenchymal cells populating the outflow tract cushions.

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The cell biology of planar cell polarity

The Journal of Cell Biology ◽

10.1083/jcb.201408039 ◽

2014 ◽

Vol 207 (2) ◽

pp. 171-179 ◽

Cited By ~ 162

Author(s):

Danelle Devenport

Keyword(s):

Cell Polarity ◽

Cell Biology ◽

Planar Cell Polarity ◽

Protein Transport ◽

Protein Localization ◽

Tissue Level ◽

Mechanical Forces ◽

Cellular Polarity ◽

Asymmetric Partitioning ◽

Local Cell

Planar cell polarity (PCP) refers to the coordinated alignment of cell polarity across the tissue plane. Key to the establishment of PCP is asymmetric partitioning of cortical PCP components and intercellular communication to coordinate polarity between neighboring cells. Recent progress has been made toward understanding how protein transport, endocytosis, and intercellular interactions contribute to asymmetric PCP protein localization. Additionally, the functions of gradients and mechanical forces as global cues that bias PCP orientation are beginning to be elucidated. Together, these findings are shedding light on how global cues integrate with local cell interactions to organize cellular polarity at the tissue level.

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Kif26b controls endothelial cell polarity through the Dishevelled/Daam1-dependent planar cell polarity–signaling pathway

Molecular Biology of the Cell ◽

10.1091/mbc.e14-08-1332 ◽

2016 ◽

Vol 27 (6) ◽

pp. 941-953 ◽

Cited By ~ 17

Author(s):

Aude Guillabert-Gourgues ◽

Beatrice Jaspard-Vinassa ◽

Marie-Lise Bats ◽

Raj N. Sewduth ◽

Nathalie Franzl ◽

...

Keyword(s):

Signaling Pathway ◽

Cell Polarity ◽

Planar Cell Polarity ◽

Cell Structure ◽

Ectopic Expression ◽

Three Dimensional ◽

Cell Polarization ◽

Directional Migration ◽

Angiogenesis Assay

Angiogenesis involves the coordinated growth and migration of endothelial cells (ECs) toward a proangiogenic signal. The Wnt planar cell polarity (PCP) pathway, through the recruitment of Dishevelled (Dvl) and Dvl-associated activator of morphogenesis (Daam1), has been proposed to regulate cell actin cytoskeleton and microtubule (MT) reorganization for oriented cell migration. Here we report that Kif26b—a kinesin—and Daam1 cooperatively regulate initiation of EC sprouting and directional migration via MT reorganization. First, we find that Kif26b is recruited within the Dvl3/Daam1 complex. Using a three-dimensional in vitro angiogenesis assay, we show that Kif26b and Daam1 depletion impairs tip cell polarization and destabilizes extended vascular processes. Kif26b depletion specifically alters EC directional migration and mislocalized MT organizing center (MTOC)/Golgi and myosin IIB cell rear enrichment. Therefore the cell fails to establish a proper front–rear polarity. Of interest, Kif26b ectopic expression rescues the siDaam1 polarization defect phenotype. Finally, we show that Kif26b functions in MT stabilization, which is indispensable for asymmetrical cell structure reorganization. These data demonstrate that Kif26b, together with Dvl3/Daam1, initiates cell polarity through the control of PCP signaling pathway–dependent activation.

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Par3 regulates Rac1 signaling and microtubule organization during planar polarization of auditory hair cells

10.1101/323022 ◽

2018 ◽

Author(s):

Andre Landin Malt ◽

Zachary Dailey ◽

Julia Holbrook-rasmussen ◽

Yuqiong Zheng ◽

Quansheng Du ◽

...

Keyword(s):

Inner Ear ◽

Cell Polarity ◽

Hair Cells ◽

Planar Cell Polarity ◽

Tissue Level ◽

Hair Bundle ◽

Microtubule Organization ◽

Reciprocal Regulation ◽

Auditory Hair Cells ◽

Pcp Signaling

AbstractIn the inner ear sensory epithelia, hair bundles atop sensory hair cells are mechanosensory apparati with planar polarized structure and orientation. This is established during development by the concerted action of tissue-level planar cell polarity (PCP) signaling and a hair cell-intrinsic, microtubule-mediated machinery. However, how various polarity signals are integrated during hair bundle morphogenesis is poorly understood. Here, we show that the conserved cell polarity protein Par3 plays a key role in planar polarization of hair cells. Par3 deletion in the inner ear resulted in defects in cochlear length, hair bundle orientation and kinocilium positioning. During PCP establishment, Par3 promotes localized Rac-Pak signaling through an interaction with Tiam1. Par3 regulates microtubule dynamics and organization, which is crucial for basal body positioning. Moreover, there is reciprocal regulation of Par3 and the core PCP molecule Vangl2. Thus, we conclude that Par3 is an effector and integrator of cell-intrinsic and tissue-level PCP signaling.One sentence summaryPar3 regulates planar polarity of auditory hair cells

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