Cone photoreceptors are assembled by unknown mechanisms into geometrically regular mosaics in many vertebrate species. The formation and maintenance of photoreceptor mosaics are speculated to require ...differential cell-cell adhesion. However, the molecular basis for this theory has yet to be identified. The retina and many other tissues express Crumbs (Crb) polarity proteins. The functions of the extracellular domains of Crb proteins remain to be understood. Here we report cell-type-specific expression of the crb2a and crb2b genes at the cell membranes of photoreceptor inner segments and Müller cell apical processes in the zebrafish retina. We demonstrate that the extracellular domains of Crb2a and Crb2b mediate a cell-cell adhesion function, which plays an essential role in maintaining the integrity of photoreceptor layer and cone mosaics. Because Crb proteins are expressed in many types of epithelia, the Crb-based cell-cell adhesion may underlie cellular patterning in other epithelium-derived tissues as well.
► In zebrafish, all types of photoreceptors and Müller cells express Crb2a ► Only green, red, and blue cones express Crb2b ► The extracellular domains of Crb2a and Crb2b mediate specific cell-cell adhesion ► Crb2-based cell adhesion is required to maintain pentameric cones and cone mosaics
Vertebrate photoreceptors are arranged into geometrically regular mosaics. Zou et al. report cell-type-specific expression of crb2a and crb2b in zebrafish retina and demonstrate that the extracellular domains of these proteins mediate specific cell-cell adhesion. This adhesion is essential for maintaining photoreceptor layer integrity and cone mosaics in zebrafish retina.
Lung adenocarcinoma (LUAD) is the most common lung cancer, which accounts for about 35–40% of all lung cancer patients. Despite therapeutic advancements in recent years, the overall survival time of ...LUAD patients still remains poor, especially KRAS mutant LUAD. Therefore, it is necessary to further explore novel targets and drugs to improve the prognos is for LUAD. Ferroptosis, an iron-dependent regulated cell death (RCD) caused by lipid peroxidation, has attracted much attention recently as an alternative target for apoptosis in LUAD therapy. Ferroptosis has been found to be closely related to LUAD at every stage, including initiation, proliferation, and progression. In this review, we will provide a comprehensive overview of ferroptosis mechanisms, its regulation in LUAD, and the application of targeting ferroptosis for LUAD therapy.
In this letter, a novel slot array antenna with a substrate-integrated coaxial line (SICL) technique is proposed. The proposed antenna has radiation slots etched homolaterally along the mean line in ...the top metallic layer of SICL and achieves a compact transverse dimension. A prototype with 5 × 10 longitudinal slots is designed and fabricated with a multilayer liquid crystal polymer (LCP) process. A maximum gain of 15.0 dBi is measured at 35.25 GHz with sidelobe levels of -28.2 dB (E-plane) and -33.1 dB (H-plane). The close correspondence between experimental results and designed predictions on radiation patterns has validated the proposed excogitation in the end.
Normal neural circuits and functions depend on proper neuronal differentiation, migration, synaptic plasticity, and maintenance. Abnormalities in these processes underlie various neurodevelopmental, ...neuropsychiatric, and neurodegenerative disorders. Neural development and maintenance are regulated by many proteins. Among them are Par3, Par6 (partitioning defective 3 and 6), and aPKC (atypical protein kinase C) families of evolutionarily conserved polarity proteins. These proteins perform versatile functions by forming tripartite or other combinations of protein complexes, which hereafter are collectively referred to as "Par complexes." In this review, we summarize the major findings on their biophysical and biochemical properties in cell polarization and signaling pathways. We next summarize their expression and localization in the nervous system as well as their versatile functions in various aspects of neurodevelopment, including neuroepithelial polarity, neurogenesis, neuronal migration, neurite differentiation, synaptic plasticity, and memory. These versatile functions rely on the fundamental roles of Par complexes in cell polarity in distinct cellular contexts. We also discuss how cell polarization may correlate with subcellular polarization in neurons. Finally, we review the involvement of Par complexes in neuropsychiatric and neurodegenerative disorders, such as schizophrenia and Alzheimer's disease. While emerging evidence indicates that Par complexes are essential for proper neural development and maintenance, many questions on their
functions have yet to be answered. Thus, Par3, Par6, and aPKC continue to be important research topics to advance neuroscience.
Abstract
Tourism is the industry with the most vitality and development potential. Today, it is the largest industry in the world. It is not only recognized by many developed countries, but also ...recognized as a priority industry by more and more developing countries and regions. Today, with the development of the knowledge economy, information has become the lifeblood of the tourism industry, and computerization has become an important factor in promoting overall economic development. And global society. This article mainly introduces the resources and management information of tourism service facilities based on the tourism management system GIS. In this article, we will study and discuss the application of GIS in tourism information systems, integrate the concept of autonomous tourism into the system, make the country a research field, and establish, verify and implement corresponding autonomous tourism information systems. The experimental results of this paper show that the construction of this system has improved the management level of map data in tourist destinations. The map data is continuously updated. The source of land is managed within a week, and the passenger flow in Sanhe area has increased by 15%. Sustainable development is a favorable guarantee.
Neurulation transforms the neuroectoderm into the neural tube. This transformation relies on reorganising the configurational relationships between the orientations of intrinsic polarities of ...neighbouring cells. These orientational intercellular relationships are established, maintained, and modulated by orientational cell adhesions (OCAs). Here, using zebrafish (Danio rerio) neurulation as a major model, we propose a new perspective on how OCAs contribute to the parallel, antiparallel, and opposing intercellular relationships that underlie the neural plate-keel-rod-tube transformation, a stepwise process of cell aggregation followed by cord hollowing. We also discuss how OCAs in neurulation may be regulated by various adhesion molecules, including cadherins, Eph/Ephrins, Claudins, Occludins, Crumbs, Na
/K
-ATPase, and integrins. By comparing neurulation among species, we reveal that antiparallel OCAs represent a conserved mechanism for the fusion of the neural tube. Throughout, we highlight some outstanding questions regarding OCAs in neurulation. Answers to these questions will help us understand better the mechanisms of tubulogenesis of many tissues.
Distinct tissue architectures arise when cells are organized in specific orientations relative to neighboring cells. These orientational intercellular relationships are established and maintained by ...cell adhesions. We propose the concept of ‘orientational cell adhesions’ (OCAs) to couple cell orientations with cell adhesions, thus offering a new perspective to study tissue morphogenesis.
A layered organization of cells is a common architectural feature of many neuronal formations. Mutations of the zebrafish gene nagie oko (nok) produce a severe disruption of retinal architecture, ...indicating a key role for this locus in neuronal patterning. We show that nok encodes a membrane-associated guanylate kinase-family scaffolding protein. Nok localizes to the vicinity of junctional complexes in retinal neuroepithelium and in the photoreceptor cell layer. Mosaic analysis indicates that the nok retinal patterning phenotype is not cell-autonomous. We propose that nok function in patterning of postmitotic neurons is mediated through neuroepithelial cells and is necessary for guiding neurons to their proper destinations in retinal laminae.
Neuronal synaptic junctions connect neurons to enable neuronal signal transmission in the nervous system. The proper establishment of synaptic connections required many adhesion molecules. ...Malfunctions of these adhesion molecules can result in neural development disorders and neuropsychiatric disorders. How specific synapses are established by various adhesion molecules for proper neural circuitry is a fundamental question of neuroscience. SynCAMs, also named CADMs, Necl, etc., are among the many adhesion proteins found in synapses. Here, we review the current understanding of the physical properties of SynCAMs and their roles in axon pathfinding, myelination, synaptogenesis, and synaptic plasticity. In addition, we discuss the involvement of SynCAMs in neuropsychiatric disorders. Finally, we propose that SynCAM functions can be better viewed and understood from the perspective of orientational cell adhesions (OCAs). In particular, we discuss the possibilities of how SynCAMs can be regulated at the cell-type specific expression, transcription variants, posttranslational modification, and subcellular localization to modulate the diversity of SynCAMs as OCA molecules. Being major components of the synapses, SynCAMs continue to be an important research topic of neuroscience, and many outstanding questions are waiting to be answered.
Photoreceptor synaptic terminals are responsible for transmitting visual information to downstream neurons. In vertebrate retinas, photoreceptor synaptic terminals are of different sizes and ...structures. The molecular mechanisms that underlie photoreceptor synaptic development are not clearly understood. Here, we have systematically examined the size variations in the synaptic terminals of cone and rod photoreceptors in the adult zebrafish retina. We reveal that the average cone pedicle sizes expand in the order of UV, blue, green, and red cones, echoing the increasing maximally sensitive wavelengths of the opsins expressed in the corresponding cone types. In addition, rod spherules are smaller than all cone pedicles. The terminals of each photoreceptor type also display distinct regional variations across the retina and between males and females. These findings establish the basis for using the zebrafish retina to study the molecular mechanisms that regulate the sizes and structures of photoreceptor terminals for proper visual functions.
•The average sizes of pedicles increase in the order of UV, blue, green, and red cones.•Rod spherules are smaller than the pedicles of all types of cones.•Sex-dependent differences exist in photoreceptor terminal sizes.•Photoreceptor terminal sizes also display regional variations across the retina.
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