scholarly journals PAPC mediates self/non–self-distinction during Snail1-dependent tissue separation

2015 ◽  
Vol 208 (6) ◽  
pp. 839-856 ◽  
Author(s):  
Olivia Luu ◽  
Erich W. Damm ◽  
Serge E. Parent ◽  
Debanjan Barua ◽  
Tamara H.L. Smith ◽  
...  
Keyword(s):  
Cell Sorting ◽  
Planar Cell Polarity ◽  
Adherens Junction ◽  
Distinct Type ◽  
Adhesive Contact ◽  
Cell Level ◽  
Recognition Mechanism ◽  
Tissue Separation ◽  
Self Recognition ◽  
Cleft Formation

Cleft-like boundaries represent a type of cell sorting boundary characterized by the presence of a physical gap between tissues. We studied the cleft-like ectoderm–mesoderm boundary in Xenopus laevis and zebrafish gastrulae. We identified the transcription factor Snail1 as being essential for tissue separation, showed that its expression in the mesoderm depends on noncanonical Wnt signaling, and demonstrated that it enables paraxial protocadherin (PAPC) to promote tissue separation through two novel functions. First, PAPC attenuates planar cell polarity signaling at the ectoderm–mesoderm boundary to lower cell adhesion and facilitate cleft formation. Second, PAPC controls formation of a distinct type of adhesive contact between mesoderm and ectoderm cells that shows properties of a cleft-like boundary at the single-cell level. It consists of short stretches of adherens junction–like contacts inserted between intermediate-sized contacts and large intercellular gaps. These roles of PAPC constitute a self/non–self-recognition mechanism that determines the site of boundary formation at the interface between PAPC-expressing and -nonexpressing cells.

Targeting of the myosin-I myr 3 to intercellular adherens type junctions induced by dominant active Cdc42 in HeLa cells

1998 ◽  
Vol 111 (18) ◽  
pp. 2779-2788 ◽  
Author(s):  
H.E. Stoffler ◽  
U. Honnert ◽  
C.A. Bauer ◽  
D. Hofer ◽  
H. Schwarz ◽  
...  
Keyword(s):  
Hela Cells ◽  
Adherens Junction ◽  
Intercellular Junctions ◽  
Distinct Type ◽  
Beta Catenin ◽  
Tail Domain ◽  
Filamentous Actin ◽  
Myosin I ◽  
Myosin Motor Domain ◽  
Constitutively Active

Myr 3, a member of the myosin-I family from rat, is shown in this study to be localized at adherens-type intercellular junctions in epithelial and nonepithelial tissues. Formation of intercellular junctions and the accompanying recruitment of myr 3 to these junctions involves signaling by the Rho subfamily of small GTP-binding proteins. This conclusion is based on studies with HtTA-1 HeLa cells that were induced by overexpression of constitutively active Cdc42Hs to form typical adherens-type intercellular junctions enriched in cadherins (N-cadherin), beta-catenin, filamentous actin and myr 3. Recruitement of myr 3 to Cdc42-induced adherens junctions in HeLa cells was dependent on a short region of the tail domain and a functional myosin motor domain, but was independent of its myosin-I tail homology and SH3 regions. Overexpression of constitutively active Rac1 induced a distinct type of adherens junction in HeLa cells that was characterized by elaborate intercellular interdigitations enriched in N-cadherin, beta-catenin and F-actin. Myr 3 was often present, but not specifically enriched in the intercellular junctions induced by constitutively active Rac1.

Small peptide–mediated self-recognition prevents cannibalism in predatory nematodes

Science ◽  
2019 ◽  
Vol 364 (6435) ◽  
pp. 86-89 ◽  
Author(s):  
James W. Lightfoot ◽  
Martin Wilecki ◽  
Christian Rödelsperger ◽  
Eduardo Moreno ◽  
Vladislav Susoy ◽  
...  
Keyword(s):  
Hypervariable Region ◽  
Recognition System ◽  
Natural World ◽  
Single Amino Acid ◽  
Biological Processes ◽  
Small Peptide ◽  
Recognition Mechanism ◽  
Self Recognition ◽  
C Terminus ◽  
Molecular Machinery

Self-recognition is observed abundantly throughout the natural world, regulating diverse biological processes. Although ubiquitous, often little is known of the associated molecular machinery, and so far, organismal self-recognition has never been described in nematodes. We investigated the predatory nematode Pristionchus pacificus and, through interactions with its prey, revealed a self-recognition mechanism acting on the nematode surface, capable of distinguishing self-progeny from closely related strains. We identified the small peptide SELF-1, which is composed of an invariant domain and a hypervariable C terminus, as a key component of self-recognition. Modifications to the hypervariable region, including single–amino acid substitutions, are sufficient to eliminate self-recognition. Thus, the P. pacificus self-recognition system enables this nematode to avoid cannibalism while promoting the killing of competing nematodes.

scholarly journals CfLec-3 from scallop: an entrance to non-self recognition mechanism of invertebrate C-type lectin

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Jialong Yang ◽  
Mengmeng Huang ◽  
Huan Zhang ◽  
Lingling Wang ◽  
Hao Wang ◽  
...  
Keyword(s):  
Recognition Mechanism ◽  
Self Recognition

scholarly journals Self-Recognition Mechanism between Skin and Suckers Prevents Octopus Arms from Interfering with Each Other

2014 ◽  
Vol 24 (11) ◽  
pp. 1271-1275 ◽  
Author(s):  
Nir Nesher ◽  
Guy Levy ◽  
Frank W. Grasso ◽  
Binyamin Hochner
Keyword(s):  
Recognition Mechanism ◽  
Self Recognition

A Study of Method on Evaluation of Aircraft's IR Image Stealth Effectiveness

2014 ◽  
Vol 926-930 ◽  
pp. 1651-1655
Author(s):  
Shi Jie Chai ◽  
Zhong Xiang Tong ◽  
Chao Zhe Wang
Keyword(s):  
Computer Simulation ◽  
Target Tracking ◽  
Ir Detectors ◽  
Detector Performance ◽  
Recognition Mechanism ◽  
Evaluation Indexes ◽  
Self Recognition ◽  
Validation Experiment ◽  
Current Assessment

Drawing up evaluation indexes is key of Evaluation of aircrafts IR stealth effectiveness. To solve the problem of high costs and great difficulties in indexs validation experiment, this paper was using method of computer simulation to obtain images and computer judging to evaluating quantitatively of Aircrafts stealth effectiveness. Closely integrating with IR detectors recognition mechanism, the evaluation indexes were determined that can assess IR stealth effectiveness quantitatively when aircraft adopts different stealth technics, different interference measures, and confronts different IR detectors. These evaluation indexes overcome the shortcomings in current assessment, such as impacted greater by detector performance, can not reflect active IR stealths action, e.g. IR decoys interference, and deviate large from IR detectors self-recognition and target tracking result.

scholarly journals Tissue fluidity mediated by adherens junction dynamics promotes planar cell polarity-driven ommatidial rotation

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Nabila Founounou ◽  
Reza Farhadifar ◽  
Giovanna M. Collu ◽  
Ursula Weber ◽  
Michael J. Shelley ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Cell Polarity ◽  
Planar Cell Polarity ◽  
Adherens Junction ◽  
Live Imaging ◽  
Cellular Migration ◽  
Imaging Analysis ◽  
Ommatidial Rotation ◽  
Eye Morphogenesis

AbstractThe phenomenon of tissue fluidity—cells’ ability to rearrange relative to each other in confluent tissues—has been linked to several morphogenetic processes and diseases, yet few molecular regulators of tissue fluidity are known. Ommatidial rotation (OR), directed by planar cell polarity signaling, occurs during Drosophila eye morphogenesis and shares many features with polarized cellular migration in vertebrates. We utilize in vivo live imaging analysis tools to quantify dynamic cellular morphologies during OR, revealing that OR is driven autonomously by ommatidial cell clusters rotating in successive pulses within a permissive substrate. Through analysis of a rotation-specific nemo mutant, we demonstrate that precise regulation of junctional E-cadherin levels is critical for modulating the mechanical properties of the tissue to allow rotation to progress. Our study defines Nemo as a molecular tool to induce a transition from solid-like tissues to more viscoelastic tissues broadening our molecular understanding of tissue fluidity.

scholarly journals Morphogenetic forces planar polarize LGN/Pins in the embryonic head during Drosophila gastrulation

2022 ◽  
Author(s):  
Jaclyn M Camuglia ◽  
Soline Chanet ◽  
Adam C Martin
Keyword(s):  
Planar Cell Polarity ◽  
Adherens Junction ◽  
Drosophila Embryo ◽  
Spindle Orientation ◽  
Planar Polarity ◽  
Ventral Furrow ◽  
Adherens Junction Protein ◽  
Early Drosophila Embryo ◽  
Junction Protein

Spindle orientation is often achieved by a complex of Pins/LGN, Mud/NuMa, Gαi, and Dynein, which interacts with astral microtubules to rotate the spindle. Cortical Pins/LGN recruitment serves as a critical step in this process. Here, we identify Pins-mediated planar cell polarized divisions in several of the mitotic domains of the early Drosophila embryo. We found that neither planar cell polarity pathways nor planar polarized myosin localization determined division orientation; instead, our findings strongly suggest that Pins planar polarity and force generated from mesoderm invagination are important. Disrupting Pins polarity via overexpression of a myristoylated version of Pins caused randomized division angles. We found that disrupting forces through chemical inhibitors, laser ablation, and depletion of an adherens junction protein disrupted Pins planar polarity and spindle orientation. Furthermore, snail depletion, which abrogates ventral furrow forces, disrupted Pins polarization and spindle orientation, suggesting that morphogenetic movements and resulting forces transmitted through the tissue can polarize Pins and orient division. Thus, morphogenetic forces associated with mesoderm invagination result in planar polarized Pins to mediate division orientation at a distant region of the embryo during morphogenesis. To our knowledge, this is the first in vivo example where mechanical force has been shown to polarize Pins to mediate division orientation.

scholarly journals Self-recognition mechanism of MamA, a magnetosome-associated TPR-containing protein, promotes complex assembly

2011 ◽  
Vol 108 (33) ◽  
pp. E480-E487 ◽  
Author(s):  
N. Zeytuni ◽  
E. Ozyamak ◽  
K. Ben-Harush ◽  
G. Davidov ◽  
M. Levin ◽  
...  
Keyword(s):  
Recognition Mechanism ◽  
Complex Assembly ◽  
Self Recognition

scholarly journals The adherens junction–associated LIM domain protein Smallish regulates epithelial morphogenesis

2018 ◽  
Vol 217 (3) ◽  
pp. 1079-1095 ◽  
Author(s):  
Hamze Beati ◽  
Irina Peek ◽  
Paulina Hordowska ◽  
Mona Honemann-Capito ◽  
Jade Glashauser ◽  
...  
Keyword(s):  
Planar Cell Polarity ◽  
Adherens Junction ◽  
Epithelial Morphogenesis ◽  
Lim Domain ◽  
Core Component ◽  
Apical Constriction ◽  
Binding Partner ◽  
Actomyosin Contractility ◽  
Lim Domain Protein ◽  
Embryonic Morphogenesis

In epithelia, cells adhere to each other in a dynamic fashion, allowing the cells to change their shape and move along each other during morphogenesis. The regulation of adhesion occurs at the belt-shaped adherens junction, the zonula adherens (ZA). Formation of the ZA depends on components of the Par–atypical PKC (Par-aPKC) complex of polarity regulators. We have identified the Lin11, Isl-1, Mec-3 (LIM) protein Smallish (Smash), the orthologue of vertebrate LMO7, as a binding partner of Bazooka/Par-3 (Baz), a core component of the Par-aPKC complex. Smash also binds to Canoe/Afadin and the tyrosine kinase Src42A and localizes to the ZA in a planar polarized fashion. Animals lacking Smash show loss of planar cell polarity (PCP) in the embryonic epidermis and reduced cell bond tension, leading to severe defects during embryonic morphogenesis of epithelial tissues and organs. Overexpression of Smash causes apical constriction of epithelial cells. We propose that Smash is a key regulator of morphogenesis coordinating PCP and actomyosin contractility at the ZA.

scholarly journals Wnt-11 and Fz7 reduce cell adhesion in convergent extension by sequestration of PAPC and C-cadherin

2012 ◽  
Vol 198 (4) ◽  
pp. 695-709 ◽  
Author(s):  
Bianca Kraft ◽  
Corinna D. Berger ◽  
Veronika Wallkamm ◽  
Herbert Steinbeisser ◽  
Doris Wedlich
Keyword(s):  
Cell Adhesion ◽  
Xenopus Laevis ◽  
Cell Polarity ◽  
Cell Sorting ◽  
Planar Cell Polarity ◽  
Convergent Extension ◽  
Membrane Stabilization ◽  
Dynamic Modulation ◽  
Interaction Domains ◽  
Shape Changes

Wnt-11/planar cell polarity signaling polarizes mesodermal cells undergoing convergent extension during Xenopus laevis gastrulation. These shape changes associated with lateral intercalation behavior require a dynamic modulation of cell adhesion. In this paper, we report that Wnt-11/frizzled-7 (Fz7) controls cell adhesion by forming separate adhesion-modulating complexes (AMCs) with the paraxial protocadherin (PAPC; denoted as AMCP) and C-cadherin (denoted as AMCC) via distinct Fz7 interaction domains. When PAPC was part of a Wnt-11–Fz7 complex, its Dynamin1- and clathrin-dependent internalization was blocked. This membrane stabilization of AMCP (Fz7/PAPC) by Wnt-11 prevented C-cadherin clustering, resulting in reduced cell adhesion and modified cell sorting activity. Importantly, Wnt-11 did not influence C-cadherin internalization; instead, it promoted the formation of AMCC (Fz7/Cadherin), which competed with cis-dimerization of C-cadherin. Because PAPC and C-cadherin did not directly interact and did not form a joint complex with Fz7, we suggest that Wnt-11 triggers the formation of two distinct complexes, AMCC and AMCP, that act in parallel to reduce cell adhesion by hampering lateral clustering of C-cadherin.

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