Morphological Transition Research Articles

PD37-01 THE CADHERIN-CATENIN COMPLEX IS CRUCIAL FOR THE INITIAL STEP OF NEPHRON FORMATION

You have accessJournal of UrologyCME1 Apr 2023PD37-01 THE CADHERIN-CATENIN COMPLEX IS CRUCIAL FOR THE INITIAL STEP OF NEPHRON FORMATION Balint Der, Helena Bugacov, Muskaan Singh, and Andrew P. McMahon Balint DerBalint Der More articles by this author , Helena BugacovHelena Bugacov More articles by this author , Muskaan SinghMuskaan Singh More articles by this author , and Andrew P. McMahonAndrew P. McMahon More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003335.01AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Congenital anomalies of the kidney and urinary tract contribute to a significant share of pre- and neonatal developmental abnormalities. In nephron formation, canonical Wnt-signaling induces mesenchymal nephron progenitor cells (NPCs) to aggregate and epithelialize forming the renal vesicle (RV), the nephron precursor. β-catenin is essential for the inductive process though the mechanism of morphological transition is not well understood (Park et al., 2007). We hypothesized that ß-catenin also directs RV formation through its critical role in cadherin mediated cell adhesion, the potential redundancy amongst cadherin members confounding earlier genetic studies (Dahl et al., 2002). METHODS: Using a chemically defined culture medium replicating in vivo NPC signaling, we examined the requirement for multiple cadherin adhesion complex components in the canonical Wnt signaling induced aggregation of induced NPCs in vitro. RESULTS: Removal of extracellular calcium, an essential ion in cadherin complexes, resulted in reversible loss of cell-cell contacts, consistent with a role for cadherin adhesion in the aggregation process. In vitro knockout of β-catenin inhibited the induction and aggregation of NPCs replicating the findings of the in vivo loss-of-function mouse experiments. Interestingly, the deletion of α-catenin phenocopied the results of β-catenin knockout experiments blocking cell aggregation providing further evidence for the role of the cadherin-catenin complex in the aggregation. To identify the cadherin members of the adhesion complex, we screened in vitro bulk RNA-seq. dataset and validated the presence of four cadherin proteins by immunofluorescent staining. The quadruple removal of in vitro expressed cadherins replicated the previously characterized phenomenon of inhibited aggregation of the NPCs. CONCLUSIONS: The aggregation of NPCs in vitro is exclusively mediated via the cadherin-catenin complex which models the initial step of nephrogenesis in vivo. A mechanistic insight into NPC aggregation fits within the larger framework of how a healthy kidney is formed and might explain the genetic background of certain congenital kidney anomalies. Source of Funding: National Institute of Diabetes and Digestive and Kidney Diseases (R01 DK054364 Cell Interaction in Development of the Mammalian Kidney) © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e986 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Balint Der More articles by this author Helena Bugacov More articles by this author Muskaan Singh More articles by this author Andrew P. McMahon More articles by this author Expand All Advertisement PDF downloadLoading ...

Expectations of the Size Evolution of Massive Galaxies at 3 ≤ z ≤ 6 from the TNG50 Simulation: The CEERS/JWST View

We present a catalog of about 25,000 images of massive (M ⋆ ≥ 109 M ⊙) galaxies at redshifts 3 ≤ z ≤ 6 from the TNG50 cosmological simulation, tailored for observations at multiple wavelengths carried out with JWST. The synthetic images were created with the SKIRT radiative transfer code, including the effects of dust attenuation and scattering. The noiseless images were processed with the mirage simulator to mimic the Near Infrared Camera (NIRCam) observational strategy (e.g., noise, dithering pattern, etc.) of the Cosmic Evolution Early Release Science (CEERS) survey. In this paper, we analyse the predictions of the TNG50 simulation for the size evolution of galaxies at 3 ≤ z ≤ 6 and the expectations for CEERS to probe that evolution. In particular, we investigate how sizes depend on the wavelength, redshift, mass, and angular resolution of the images. We find that the effective radius accurately describes the three-dimensional half-mass–radius of the TNG50 galaxies. Sizes observed at 2 μm are consistent with those measured at 3.56 μm at all redshifts and masses. At all masses, the population of higher-z galaxies is more compact than their lower-z counterparts. However, the intrinsic sizes are smaller than the mock observed sizes for the most massive galaxies, especially at z ≲ 4. This discrepancy between the mass and light distributions may point to a transition in the galaxy morphology at z = 4–5, where massive compact systems start to develop more extended stellar structures. 22 22 Data publicly released at https://www.tng-project.org/costantin22.

Molecular Insights on Morphology, Composition, and Stability of Mixed Micelles Formed by Ionic Surfactant and Nonionic Block Copolymer in Water Using Coarse-Grained Molecular Dynamics Simulations.

The nanoscale association domains are the ultimate determinants of the macroscopic properties of complex fluids involving amphiphilic polymers and surfactants, and hence, it is foremost important to understand the role of polymer/surfactant concentration on these domains. We have used coarse-grained molecular dynamics simulations to investigate the effect of polymer/surfactant concentration on the morphology of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO, i.e., pluronics or poloxamers) block copolymer, and ionic surfactants sodium dodecyl sulfate (SDS), mixed micelles in aqueous solution. The proclivity of the surfactant to form the mixed micelles is also probed using umbrella sampling simulations. In this study, we observed that the core of the pluronic + SDS formed mixed micelles consists of PPO, the alkyl tail of SDS, and some water molecules, whereas the PEO, water, and sulfate headgroups of SDS form a shell, consistent with experimental observations. The micelles are spherical at high-pluronic/low-SDS compositions, ellipsoidal at high-SDS/low-pluronic compositions, and wormlike-cylindrical at high-pluronic/high-SDS compositions. The transitions in micelle morphology are governed by the solvent accessible surface area of mixed aggregates, electrostatic repulsion between SDS-headgroups, and dehydration of PEO and PPO segments. The free energy barrier for SDS escape is much higher in mixed micelles than in pure SDS micelles, indicating a stronger tendency for SDS to form pluronic-SDS mixed micelles.

Rapid formation of bioaggregates and morphology transition to biofilm streamers induced by pore-throat flows

Bioaggregates are condensed porous materials comprising microbes, organic and inorganic matters, and water. They are commonly found in natural and engineered porous media and often cause clogging. Despite their importance, the formation mechanism of bioaggregates in porous media systems is largely unknown. Through microfluidic experiments and direct numerical simulations of fluid flow, we show that the rapid bioaggregation is driven by the interplay of the viscoelastic nature of biomass and hydrodynamic conditions at pore throats. At an early stage, unique flow structures around a pore throat promote the biomass attachment at the throat. Then, the attached biomass fluidizes when the shear stress at the partially clogged pore throat reaches a critical value. After the fluidization, the biomass is displaced and accumulated in the expansion region of throats forming bioaggregates. We further find that such criticality in shear stress triggers morphological changes in bioaggregates from rounded- to streamer-like shapes. This knowledge was used to control the clogging of throats by tuning the flow conditions: When the shear stress at the throat exceeded the critical value, clogging was prevented. The bioaggregation process did not depend on the detailed pore-throat geometry, as we reproduced the same dynamics in various pore-throat geometries. This study demonstrates that pore-throat structures, which are ubiquitous in porous media systems, induce bioaggregation and can lead to abrupt disruptions in flow.

Regularities of Modifying, Morphology and Properties of Thermoplastics Containing Polyvinylpyrrolidone

The peculiarities of modifying polyamide 66/6 and polystyrene thermoplastics with polyvinylpyrrolidone in the viscous state have been studied. By applying in-strumental methods, the changes in morphology and phase transitions of modified materials have been revealed. The influence of the modifier on the strength and thermo-physical properties of the researched thermoplastics was determined.

From Balloon to Crystalline Structure in the Calcium Phosphate Flow-Driven Chemical Garden.

We have studied the calcium phosphate precipitation reaction by producing chemical gardens in a controlled manner using a three-dimensional flow-driven technique. The injection of the phosphate containing solution into the calcium ion reservoir has resulted in structures varying from membranes to crystals. Dynamical phase diagrams are constructed by varying chemical composition and flow rates from which three different growth mechanisms have been revealed. The microstructural analysis by scanning electron microscopy and powder X-ray diffraction confirmed the morphological transition from membrane tubes to crystalline branches upon decreasing pH.

Molecular-Level Control of Thermal and Morphological Transitions in Semi-Aromatic Polyamides by Cu(I)-Catalyzed Azide–Alkyne Click Polymerization

Molecular-Level Control of Thermal and Morphological Transitions in Semi-Aromatic Polyamides by Cu(I)-Catalyzed Azide–Alkyne Click Polymerization

Analysis of Influencing Factors in the Preparation of Mullite Whiskers from Recovering Silicon-Rich Waste under Low-Temperature Conditions.

A large amount of catalyst waste containing silicon is deposited or buried every year, resulting in serious environmental pollution and a waste of resources. In this paper, a method to prepare mullite whiskers by recycling silica-rich waste under low-temperature conditions was investigated. The effects of raw materials, sintering temperature, catalyst addition, holding time and co-solvent addition on the structure, morphology and phase transition of the synthesized whiskers were investigated and characterized with SEM, XRD, TEM, TG and DTA. The results show that the addition of 10% Na2SO4 as the liquid-phase mass transfer medium could effectively improve the crystallization efficiency of mullite whiskers, while providing an ideal living environment for the growth of whiskers. The crystallinity and uniformity of mullite were positively correlated with the addition of aluminum fluoride trihydrate and the holding time, respectively. The growth law and conditions of mullite whiskers are discussed, and the optimal growth process conditions of mullite whiskers were optimized. The optimal conditions for mullite whiskers were determined as follows: the addition of aluminum fluoride is 5 wt%, the sintering temperature is 825 °C, and the holding time is 5 h at the time of sintering. This work offers new prospects for the industrial production of mullite whiskers from recycled silica-rich waste.

A new juvenile sauropod specimen from the Middle Jurassic Dongdaqiao Formation of East Tibet.

Jurassic strata are widely distributed in the eastern part of Tibet Autonomous Region, and have yielded many dinosaur bones. However, none of these specimens has been studied extensively, and some remain unprepared. Here we provide a detailed description of some new sauropod material, including several cervical vertebrae and a nearly complete scapula, recovered from the Middle Jurassic of Chaya County, East Tibet. The cervical vertebrae have short centra that bear ventral midline keels, as in many non-neosauropod sauropods such as Shunosaurus. Moreover, the cervical centra display deep lateral excavations, partitioned by a septum. The scapula has proximal and distal ends that are both expanded as in mamenchisaurids and neosauropods. However, relatively small body size and lack of fusion of neurocentral sutures in the cervical vertebrae suggest that the available material is from a juvenile, and the length of the cervical centra may have increased relative to the size of the rest of the skeleton in later ontogenetic stages. Phylogenetic analysis provides limited evidence that the new Tibetan sauropod specimen belongs to Eusauropoda, being more derived than Shunosaurus, but is basal to Mamenchisauridae. The new material provides important information on the morphological transition between Shunosaurus and mamenchisaurids, and extends the known biogeographic range of early-diverging sauropods in the Middle Jurassic of East Asia.

Preparation of Macroscopic Low-Density Gold Foams with Good Machinability

Uniform, macroscopic monoliths (ranging from a few millimeters to a centimeter) of low-density gold foams with ~95% porosity and ~10-μm-diameter pores were prepared by the casting of gold-coated polystyrene core-shell particles followed by the thermal removal of the polymer core. The Au foams were composed of unique hollow gold spheres and showed superior mechanical integrity and resilience compared to the foams we previously reported. Highly efficient seeding and electroless gold-plating methods in this study caused a significant morphological transition in the gold coatings from coarse particles to fine particles, and finally, to a continuous layer. A modified, scalable casting approach to form large uniform monoliths (up to ~1-cm diameter) and a gentle baking condition to minimize undesirable densification of the final foams enabled us to develop a simple, efficient synthetic route to nanostructured macroscopic low-density gold foams. To demonstrate the improved mechanical stability and machinability, a representative monolithic Au foam (~0.9 g/cm3) was carefully cut into the hollow cylinder of gold foams by a series of machining and processing steps. Finally, we tried to understand the unique mechanical behaviors and properties of this gold foam by nanoindentation measurement.

Preservation of active components in olive leaf extract by spray drying method in biodegradable polymers: Optimization, in vitro gastrointestinal digestion and application.

Encapsulation of the bioactive ingredients in biodegradable and edible polymers is an alternative novel application method to keep these kind of natural products stable. The purpose is to optimize the encapsulation system of olive leaf extract by spray drying method, and to apply the products into a model food. Olive leaf extract was encapsulated in arabic gum/maltodextrin blend by spray drying method. Combined design approach under I-optimal design type was used to optimize the system. Characterisation studies under moisture content, water activity, solubility, bulk density, tapped density, Carr index, particle size distribution, powder morphology and glass transition temperature were applied to the microparticles obtained under optimum conditions. The bioavailability of the encapsulated active material was tested by in vitro gastrointestinal digestion. Furthermore, microparticles produced under optimum conditions were also evaluated for a potential functional food application. The optimum conditions were achieved by arabic gum/maltodextrin (3.7:6.3) with 10% (w/v) in the mixture of wall material and active material under 165.5°C to achieve maximum encapsulation efficiency (86.92%), encapsulation yield (71.32%) and antioxidant activity (5.74 mg Trolox equivalent antioxidant capacity/g dry microparticle). Olive leaf extract encapsulated in arabic gum/maltodextrin may be a good alternative additive to prevent the lipid oxidation in fat-containing food products as well as improvement of the product quality by functional properties.

Rectangular-Phase Tellurene on Ni(111) from Monolayer Films to Periodic Striped Patterns.

As an emerging member of monoelemental two-dimensional (2D) materials, 2D tellurium (tellurene) has recently attracted intensive attention due to its polymorphism arising from the multivalent nature and fascinating properties such as wide-range band gaps, high carrier mobilities, etc. Herein, we predict the formation of a rectangular-phase tellurene on Ni(111) by first-principles density functional theory (DFT) calculations and realize its direct syntheses and characterizations by molecular beam epitaxy (MBE) and scanning tunneling microscopy (STM). We reveal that the monolayer rectangular tellurene and underlying Ni(111) substrate are strongly coupled, along with good lattice registry along two mutually perpendicular directions, which serves as the key driving force for the tellurene formation. We also uncover the unique morphological transitions of Te/Ni(111) from rectangular tellurene monolayer, to uniform periodic striped patterns at the second layer, and then to thick striped patterns. This work should offer valuable insights for the substrate-mediated syntheses of monoelemental 2D materials, thus propelling their phase engineering and intriguing property explorations.

Syk inhibitors protect against microglia-mediated neuronal loss in culture.

Microglia are brain macrophages and play beneficial and/or detrimental roles in many brain pathologies because of their inflammatory and phagocytic activity. Microglial inflammation and phagocytosis are thought to be regulated by spleen tyrosine kinase (Syk), which is activated by multiple microglial receptors, including TREM2 (Triggering Receptor Expressed on Myeloid Cells 2), implicated in neurodegeneration. Here, we have tested whether Syk inhibitors can prevent microglia-dependent neurodegeneration induced by lipopolysaccharide (LPS) in primary neuron-glia cultures. We found that the Syk inhibitors BAY61-3606 and P505-15 (at 1 and 10 μM, respectively) completely prevented the neuronal loss induced by LPS, which was microglia-dependent. Syk inhibition also prevented the spontaneous loss of neurons from older neuron-glia cultures. In the absence of LPS, Syk inhibition depleted microglia from the cultures and induced some microglial death. However, in the presence of LPS, Syk inhibition had relatively little effect on microglial density (reduced by 0-30%) and opposing effects on the release of two pro-inflammatory cytokines (IL-6 decreased by about 45%, TNFα increased by 80%). Syk inhibition also had no effect on the morphological transition of microglia exposed to LPS. On the other hand, inhibition of Syk reduced microglial phagocytosis of beads, synapses and neurons. Thus, Syk inhibition in this model is most likely neuroprotective by reducing microglial phagocytosis, however, the reduced microglial density and IL-6 release may also contribute. This work adds to increasing evidence that Syk is a key regulator of the microglial contribution to neurodegenerative disease and suggests that Syk inhibitors may be used to prevent excessive microglial phagocytosis of synapses and neurons.

Characterization of Virulence Factors in Candida Species Causing Candidemia in a Tertiary Care Hospital in Bangkok, Thailand.

Candidemia is often associated with high mortality, and Candida albicans, Candida tropicalis, Candida glabrata, and Candida parapsilosis are common causes of this disease. The pathogenicity characteristics of specific Candida spp. that cause candidemia in Thailand are poorly understood. This study aimed to characterize the virulence factors of Candida spp. Thirty-eight isolates of different Candida species from blood cultures were evaluated for their virulence properties, including exoenzyme and biofilm production, cell surface hydrophobicity, tissue invasion, epithelial cell damage, morphogenesis, and phagocytosis resistance; the identity and frequency of mutations in ERG11 contributing to azole-resistance were also determined. C. albicans had the highest epithelial cell invasion rate and phospholipase activity, with true hyphae formation, whereas C. tropicalis produced the most biofilm, hydrophobicity, protease activity, and host cell damage and true hyphae formation. ERG11 mutations Y132F and S154F were observed in all azole-resistant C. tropicalis. C. glabrata had the most hemolytic activity while cell invasion was low with no morphologic transition. C. glabrata was more easily phagocytosed than other species. C. parapsilosis generated pseudohyphae but not hyphae and did not exhibit any trends in exoenzyme production. This knowledge will be crucial for understanding the pathogenicity of Candida spp. and will help to explore antivirulence-based treatment.

Predicting non-equilibrium folding behavior of polymer chains using the steepest-entropy-ascent quantum thermodynamic framework.

The steepest-entropy-ascent quantum thermodynamic (SEAQT) framework is used to explore the influence of heating and cooling on polymer chain folding kinetics. The framework predicts how a chain moves from an initial non-equilibrium state to stable equilibrium along a unique thermodynamic path. The thermodynamic state is expressed by occupation probabilities corresponding to the levels of a discrete energy landscape. The landscape is generated using the Replica Exchange Wang-Landau method applied to a polymer chain represented by a sequence of hydrophobic and polar monomers with a simple hydrophobic-polar amino acid model. The chain conformation evolves as energy shifts among the levels of the energy landscape according to the principle of steepest entropy ascent. This principle is implemented via the SEAQT equation of motion. The SEAQT framework has the benefit of providing insight into structural properties under non-equilibrium conditions. Chain conformations during heating and cooling change continuously without sharp transitions in morphology. The changes are more drastic along non-equilibrium paths than along quasi-equilibrium paths. The SEAQT-predicted kinetics are fitted to rates associated with the experimental intensity profiles of cytochrome c protein folding with Rouse dynamics.

Evaluation of citrus pectin capped copper sulfide nanoparticles against Candidiasis causing Candida biofilms

The incidence of candidiasis has significantly increased globally in recent decades, and it is a significant source of morbidity and mortality, particularly in critically ill patients. Candida sp. ability to generate biofilms is one of its primary pathogenic traits. Drug-resistant strains have led to clinical failures of traditional antifungals, necessitating the development of a more modern therapy that can inhibit biofilm formation and enhance Candida sp. sensitivity to the immune system. The present study reports the anticandidal potential of pectin-capped copper sulfide nanoparticles (pCuS NPs) against Candida albicans. The pCuS NPs inhibit C. albicans growth at a minimum inhibitory concentration (MIC) of 31.25 μM and exhibit antifungal action by compromising membrane integrity and overproducing reactive oxygen species. The pCuS NPs, at their biofilm inhibitory concentration (BIC) of 15.63 μM, effectively inhibited C. albicans cells adhering to the glass slides, confirmed by light microscopy and scanning electron microscopy. Phase contrast microscopy pictures revealed that NPs controlled the morphological transitions between the yeast and hyphal forms by limiting conditions that led to filamentation and reducing hyphal extension. In addition, C. albicans showed reduced exopolysaccharide (EPS) production and exhibited less cell surface hydrophobicity (CSH) after pCuS NPs treatment. The findings suggest that pCuS NPs may be able to inhibit the emergence of virulence traits that lead to the formation of biofilms, such as EPS, CSH, and hyphal morphogenesis. The results raise the possibility of developing NPs-based therapies for C. albicans infections associated with biofilms.

Dynamics Behavior of Droplet Impact on a Controllable Curved Micropillar Array Surface Induced by a Magnetic Field.

Many fields would greatly benefit from the realization of the manipulation of droplet impact behavior by an asymmetric surface structure, such as self-cleaning, anti-icing, inkjet printing, etc. However, research on the prediction of the impact of the dynamics of small-volume droplets on the asymmetric superhydrophobic surface has been insufficient. In this study, a superhydrophobic curved micropillar array surface with controllable bending angles induced by a magnetic field was prepared. The impact and rebound behaviors of the nanoliter droplets with diameters of 100-300 μm were investigated. The experimental results showed the positive correlation between the threshold Weber number of the impact morphology transition of the droplet and the inclination angle of the micropillar. In addition, the restitution coefficient, which measures the degree of energy loss during the impact process, showed a nonmonotonic dependence on the Weber number. A critical velocity model of the impact morphology transition of the droplet on the curved micropillar array surface and a prediction model of the restitution coefficient of the droplet in different impact morphologies are suggested. Our findings will help in the design of a functional surface for manipulating the impact behavior of the droplet.

Ferritin from Mycobacterium abscessus is involved in resistance to antibiotics and oxidative stress.

Mycobacterium abscessus subsp. massiliense (Mycma) is a rapidly growing Mycobacterium belonging to the M. abscessus complex that is often associated with lung and soft tissue infection outbreaks. Mycma is resistant to many antimicrobials, including those used for treating tuberculosis. Therefore, Mycma infections are difficult to treat and may lead to high infectious complication rates. Iron is essential for bacterial growth and establishment of infection. During infection, the host reduces iron concentrations as a defense mechanism. To counteract the host-induced iron deficiency, Mycma produces siderophores to capture iron. Mycma has two ferritins (encoded by mycma_0076 and mycma_0077) modulated by different iron concentrations, which allow the survival of this pathogen during iron scarcity. In this study, we constructed knockout (Mycma 0076KO) and complemented (Mycma 0076KOc) gene strains for mycma_0076 to understand the function of 0076 ferritin. Deletion of mycma_0076 in Mycma led to the transition in colony morphology from smooth to rough, alteration of the glycopeptidolipids spectra, increased permeability of the envelope, reduction in biofilm formation, increased susceptibility to antimicrobials and hydrogen peroxide-induced oxidative stress, and decreased internalization by macrophages. This study shows that Mycma_0076 ferritin in Mycma is involved in resistance to oxidative stress and antimicrobials, and alteration of cell envelope architecture. KEY POINTS: • Deletion of the mycma_0076 gene altered colony morphology to rough; • Mycma 0076KO changed GPL profile; • Absence of Mycma_0076 ferritin results in increased susceptibility to antimicrobials and oxidative stress in Mycma. Legend: a In wild-type M. abscessus subsp. massiliensestrain, iron is captured from the environment by carboxymycobactins and mycobactins (1). Iron-dependent regulator (IdeR) proteins bind to ferrous iron (Fe+2) in the bacterial cytoplasm leading to the activation of the IdeR-Fe+2 complex (2). The activated complex binds to the promoter regions of iron-dependent genes, called iron box, which in turn help in the recruitment of RNA polymerase to promote transcription of genes such as mycma_0076 and mycma_0077 ferritin genes (3). Mycma_0076 and Mycma_0077 ferritins bind to excess iron in the medium and promote Fe2+ oxidation into ferric iron (Fe3+) and store iron molecules to be released under iron scarcity conditions. (4) Genes related to biosynthesis and transport of glycopeptidolipids (GPL) are expressed normally and the cell envelope is composed of different GPL species (colored squares represented on the cell surface (GPLs). Consequently, WT Mycma present smooth colony phenotype (5). b In Mycma 0076KO strain, the lack of ferritin 0076 causes overexpression of mycma_0077 (6), but does not restore wild-type iron homeostasis and thus may result in free intracellular iron, even in the presence of miniferritins (MaDps). The excess iron potentiates oxidative stress (7) by generating hydroxyl radicals through Fenton Reaction. During this process, through an unknown mechanism, that could involve Lsr2 (8), the expression of GPL synthesis locus is regulated positively and/or negatively, resulting in alteration of GPL composition in the membrane (as represented by different colors of squares on the cell surface), resulting in a rough colony phenotype (9). The changes of GPL can increase cell wall permeability, contributing to antimicrobial susceptibility (10).

Typhlocybinae leafhoppers (Hemiptera, Cicadellidae) from Eocene Rovno amber reveal a transition in wing venation and a defensive adaptation

AbstractThe first fossil Typhlocybinae inclusions from Eocene Rovno amber are described and illustrated. They include two new monotypic genera of the extinct tribe Protodikraneurini, Retrorsotettix n. gen. with type species R. vlaskini n. sp. and Protoparallaxis n. gen. with type species P. clavatus n. sp. Also described and illustrated are two new monotypic genera of the extant tribe Dikraneurini, Eodikraneura n. gen. with type species E. obscura n. sp. and Rovnodikra n. gen. with type species Rovnodikra longipes n. sp. Retrorsotettix is the oldest leafhopper known to exhibit a false eyespot and false leg markings on the forewing, representing an early acquisition of a defensive strategy against visual predators. Appearance of a small insect with false eyespots in the Eocene fossil record may reflect increased pressure by visual predators, especially crown ornithuromorph insectivorous birds. Such birds and small insect prey with false eyespots remain unknown in the Cretaceous. Eodikraneura exhibits a unique condition of the hind wing venation in which radius posterior and media anterior veins are confluent for a short distance but then diverge before separately reaching the submarginal vein. This presumably represents a morphological transition between the Protodikraneurini, in which hind-wing radius posterior and media anterior veins are completely separate and connected by a radial-medial crossvein, and Dikraneurini, in which radius posterior and media anterior veins are completely confluent distally. A key to genera of Protodikraneurini is provided.UUID: http://zoobank.org/f15e6f80-9708-4f5e-89a3-705f9d340a77

Precise alternating cellular pattern in the inner ear by coordinated hopping intercalations and delaminations.

The mammalian hearing organ, the organ of Corti, is one of the most organized tissues in mammals. It contains a precisely positioned array of alternating sensory hair cells (HCs) and nonsensory supporting cells. How such precise alternating patterns emerge during embryonic development is not well understood. Here, we combine live imaging of mouse inner ear explants with hybrid mechano-regulatory models to identify the processes that underlie the formation of a single row of inner hair cells (IHCs). First, we identify a previously unobserved morphological transition, termed "hopping intercalation," that allows cells differentiating toward IHC fate to "hop" under the apical plane into their final position. Second, we show that out-of-row cells with low levels of the HC marker Atoh1 delaminate. Last, we show that differential adhesion between cell types contributes to straightening of the IHC row. Our results support a mechanism for precise patterning based on coordination between signaling and mechanical forces that is likely relevant for many developmental processes.