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Planar Cell Polarity
Planar cell polarity (PCP) is the protein-mediated Cell signaling, signaling that coordinates the orientation of Cell (biology), cells in a layer of Epithelium, epithelial tissue. In vertebrates, examples of mature PCP oriented tissue are the stereo-cilia bundles in the inner ear, motile cilia of the epithelium, and cell motility in epidermal wound healing. Additionally, PCP is known to be crucial to major developmental time points including coordinating convergent extension during gastrulation and coordinating cell behavior for neural tube closure. Cells orient themselves and their neighbors by establishing asymmetric expression of PCP components on opposing cell members within cells to establish and maintain the directionality of the cells. Some of these PCP components are transmembrane proteins which can proliferate the orientation signal to the surrounding cells. Research history Planar cell polarity was first described in insects and then further defined in fruit flies (''Dro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cartoon Representation Of Planar Polarity In Fly And Mouse Epithelia
A cartoon is a type of visual art that is typically drawn, frequently Animation, animated, in an realism (arts), unrealistic or semi-realistic style. The specific meaning has evolved, but the modern usage usually refers to either: an image or series of images intended for satire, caricature, or humor; or a motion picture that relies on a sequence of illustrations for its animation. Someone who creates cartoons in the first sense is called a ''cartoonist'', and in the second sense they are usually called an ''animator''. The concept originated in the Middle Ages, and first described a preparatory drawing for a piece of art, such as a painting, fresco, tapestry, or stained glass window. In the 19th century, beginning in ''Punch (magazine), Punch'' magazine in 1843, cartoon came to refer – ironically at first – to humorous artworks in magazines and newspapers. Then it also was used for political cartoons and comic strips. When the medium developed, in the early 20th century, it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brain Ventricle
In neuroanatomy, the ventricular system is a set of four interconnected cavities known as cerebral ventricles in the brain. Within each ventricle is a region of choroid plexus which produces the circulating cerebrospinal fluid (CSF). The ventricular system is continuous with the central canal of the spinal cord from the fourth ventricle, allowing for the flow of CSF to circulate. All of the ventricular system and the central canal of the spinal cord are lined with ependyma, a specialised form of epithelium connected by tight junctions that make up the blood–cerebrospinal fluid barrier. Structure The system comprises four ventricles: * lateral ventricles right and left (one for each hemisphere) * third ventricle * fourth ventricle There are several foramina, openings acting as channels, that connect the ventricles. The interventricular foramina (also called the foramina of Monro) connect the lateral ventricles to the third ventricle through which the cerebrospinal fluid c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Polarity
Cell polarity refers to spatial differences in shape, structure, and function within a cell. Almost all cell types exhibit some form of polarity, which enables them to carry out specialized functions. Classical examples of polarized cells are described below, including epithelial cells with apical-basal polarity, neurons in which signals propagate in one direction from dendrites to axons, and migrating cells. Furthermore, cell polarity is important during many types of asymmetric cell division to set up functional asymmetries between daughter cells. Many of the key molecular players implicated in cell polarity are well conserved. For example, in metazoan cells, the complex plays a fundamental role in cell polarity. While the biochemical details may vary, some of the core principles such as negative and/or positive feedback between different molecules are common and essential to many known polarity systems. Examples of polarized cells Epithelial cells Epithelial cells adhe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cadherin
Cadherins (named for "calcium-dependent adhesion") are cell adhesion molecules important in forming adherens junctions that let cells adhere to each other. Cadherins are a class of type-1 transmembrane proteins, and they depend on calcium (Ca2+) ions to function, hence their name. Cell-cell adhesion is mediated by extracellular cadherin domains, whereas the Cadherin cytoplasmic region, intracellular cytoplasmic tail associates with numerous adaptors and signaling proteins, collectively referred to as the cadherin adhesome. Background The cadherin family is essential in maintaining cell-cell contact and regulating cytoskeletal complexes. The cadherin superfamily includes cadherins, protocadherins, desmogleins, desmocollins, and more. In structure, they share ''cadherin repeats'', which are the extracellular Ca2+-binding domains. There are multiple classes of cadherin molecules, each designated with a prefix for tissues with which it associates. Classical cadherins maintain the ton ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytoskeleton
The cytoskeleton is a complex, dynamic network of interlinking protein filaments present in the cytoplasm of all cells, including those of bacteria and archaea. In eukaryotes, it extends from the cell nucleus to the cell membrane and is composed of similar proteins in the various organisms. It is composed of three main components: microfilaments, intermediate filaments, and microtubules, and these are all capable of rapid growth and or disassembly depending on the cell's requirements. Cytoskeleton can perform many functions. Its primary function is to give the cell its shape and mechanical resistance to deformation, and through association with extracellular connective tissue and other cells it stabilizes entire tissues. The cytoskeleton can also contract, thereby deforming the cell and the cell's environment and allowing cells to migrate. Moreover, it is involved in many cell signaling pathways and in the uptake of extracellular material ( endocytosis), the segregation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
β-catenin
Catenin beta-1, also known as β-catenin (''beta''-catenin), is a protein that in humans is encoded by the ''CTNNB1'' gene. β-Catenin is a dual function protein, involved in regulation and coordination of cell–cell adhesion and gene transcription. In humans, the CTNNB1 protein is encoded by the ''CTNNB1'' gene. In ''Drosophila'', the homologous protein is called ''armadillo''. β-catenin is a subunit of the cadherin protein complex and acts as an intracellular signal transducer in the Wnt signaling pathway. It is a member of the catenin protein family and homologous to γ-catenin, also known as plakoglobin. β-Catenin is widely expressed in many tissues. In cardiac muscle, β-catenin localizes to adherens junctions in intercalated disc structures, which are critical for electrical and mechanical coupling between adjacent cardiomyocytes. Mutations and overexpression of β-catenin are associated with many cancers, including hepatocellular carcinoma, colorectal carcinom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wnt Signaling Pathway
In cellular biology, the Wnt signaling pathways are a group of signal transduction pathways which begin with proteins that pass signals into a cell through cell surface receptors. The name Wnt, pronounced "wint", is a portmanteau created from the names Wingless and Int-1. Wnt signaling pathways use either nearby cell-cell communication (paracrine) or same-cell communication (autocrine). They are highly evolutionarily conserved in animals, which means they are similar across animal species from fruit flies to humans. Three Wnt signaling pathways have been characterized: the canonical Wnt pathway, the noncanonical planar cell polarity pathway, and the noncanonical Wnt/calcium pathway. All three pathways are activated by the binding of a Wnt-protein ligand to a Frizzled family receptor, which passes the biological signal to the Dishevelled protein inside the cell. The canonical Wnt pathway leads to regulation of gene transcription, and is thought to be negatively regulated in part ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G Protein
G proteins, also known as guanine nucleotide-binding proteins, are a Protein family, family of proteins that act as molecular switches inside cells, and are involved in transmitting signals from a variety of stimuli outside a cell (biology), cell to its interior. Their activity is regulated by factors that control their ability to bind to and hydrolyze guanosine triphosphate (GTP) to guanosine diphosphate (GDP). When they are bound to GTP, they are 'on', and, when they are bound to GDP, they are 'off'. G proteins belong to the larger group of enzymes called GTPases. There are two classes of G proteins. The first function as monomeric small GTPases (small G-proteins), while the second function as heterotrimeric G protein protein complex, complexes. The latter class of complexes is made up of ''G alpha subunit, alpha'' (Gα), ''beta'' (Gβ) and ''gamma'' (Gγ) protein subunit, subunits. In addition, the beta and gamma subunits can form a stable Protein dimer, dimeric complex re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strabismus (protein)
Strabismus was originally identified as a ''Drosophila'' protein involved in planar cell polarity. Flies with mutated ''strabismus'' genes have altered development of ommatidia in their eyes. Vertebrates have two Strabismus-related proteins, VANGL1 and VANGL2 (an alternate name for the ''Drosophila'' "Strabismus" protein is "Van Gogh"). The amino acid sequence and localization studies for Strabismus indicate that it is a membrane protein. Prickle is another protein in the planar cell polarity signaling pathway. Prickle is recruited to the cell surface membrane by strabismus. In cells of the developing ''Drosophila'' wing, Prickle and Strabismus are concentrated at the cell surface membrane on the most proximal side of cells. Vertebrate cell movement VANGL2 is involved in the migration of groups of cells during vertebrate embryogenesis. Humans In humans, mutations in VANGL1 have been associated with neural tube defects including spina bifida, and with some forms of cancer incl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flamingo (protein)
Flamingo is a member of the adhesion-GPCR family of proteins. Flamingo has sequence homology to cadherins and G protein-coupled receptors (GPCR). Flamingo was originally identified as a ''Drosophila'' protein involved in planar cell polarity. Mammals have three flamingo homologs, CELSR1, CELSR2, CELSR3. In mice, all three have distinct expression patterns in organs such as the kidney, skin, and lungs, as well as the brain. Protein structure Flamingo is an atypical cadherin, with a cadherin-like extracellular domain, composed of cadherin and EGF adhesive repeats, that can bind to other Flamingo proteins expressed on neighboring cells. The transmembrane domain, however, is a 7-pass membrane domain most structurally similar to that of a G protein-coupled receptor, though it is not known to interact with G protein. Planar cell polarity Flamingo is one of the core proteins in the planar cell polarity (PCP) pathway, which is required for successful body elongation during gastrulatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cuticular Wing Hair Defect In Frizzled Mutant Flies
A cuticle (), or cuticula, is any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticle" are non- homologous, differing in their origin, structure, function, and chemical composition. Human anatomy In human anatomy, "cuticle" can refer to several structures, but it is used in general parlance, and even by medical professionals, to refer to the thickened layer of skin surrounding fingernails and toenails (the eponychium), and to refer to the superficial layer of overlapping cells covering the hair shaft ( cuticula pili), consisting of dead cells, that locks the hair into its follicle. It can also be used as a synonym for the epidermis, the outer layer of skin. Cuticle of invertebrates In zoology, the invertebrate cuticle or cuticula is a multi-layered structure outside the epidermis of many invertebrates, notably arthropods and roundworms, in which it forms an exoskeleton ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neural Tube
In the developing chordate (including vertebrates), the neural tube is the embryonic precursor to the central nervous system, which is made up of the brain and spinal cord. The neural groove gradually deepens as the neural folds become elevated, and ultimately the folds meet and coalesce in the middle line and convert the groove into the closed neural tube. In humans, neural tube closure usually occurs by the fourth week of pregnancy (the 28th day after conception). Development The neural tube develops in two ways: primary neurulation and secondary neurulation. Primary neurulation divides the ectoderm into three cell types: * The internally located neural tube * The externally located epidermis * The neural crest cells, which develop in the region between the neural tube and epidermis but then migrate to new locations # Primary neurulation begins after the neural plate forms. The edges of the neural plate start to thicken and lift upward, forming the neural folds. The center ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
