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Basal Body
A basal body (synonymous with basal granule, kinetosome, and in older cytological literature with blepharoplast) is a protein structure found at the base of a eukaryotic undulipodium (cilium or flagellum). The basal body was named by Theodor Wilhelm Engelmann in 1880. It is formed from a centriole and several additional protein structures, and is, essentially, a modified centriole. The basal body serves as a nucleation site for the growth of the axoneme microtubules. Centrioles, from which basal bodies are derived, act as anchoring sites for proteins that in turn anchor microtubules, and are known as the microtubule organizing center (MTOC). These microtubules provide structure and facilitate movement of vesicles and organelles within many eukaryotic cells. Assembly, structure Cilia and basal bodies form during quiescence or the G1 phase of the cell cycle. Before the cell enters G1 phase, i.e. before the formation of the cilium, the mother centriole serves as a component of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukarya Flagella
The eukaryotes ( ) constitute the Domain (biology), domain of Eukaryota or Eukarya, organisms whose Cell (biology), cells have a membrane-bound cell nucleus, nucleus. All animals, plants, Fungus, fungi, seaweeds, and many unicellular organisms are eukaryotes. They constitute a major group of Outline of life forms, life forms alongside the two groups of prokaryotes: the Bacteria and the Archaea. Eukaryotes represent a small minority of the number of organisms, but given their generally much larger size, their collective global biomass is much larger than that of prokaryotes. The eukaryotes emerged within the archaeal Kingdom (biology), kingdom Asgard (Archaea), Promethearchaeati and its sole phylum Promethearchaeota. This implies that there are only Two-domain system, two domains of life, Bacteria and Archaea, with eukaryotes incorporated among the Archaea. Eukaryotes first emerged during the Paleoproterozoic, likely as Flagellated cell, flagellated cells. The leading evolutiona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Cycle
The cell cycle, or cell-division cycle, is the sequential series of events that take place in a cell (biology), cell that causes it to divide into two daughter cells. These events include the growth of the cell, duplication of its DNA (DNA replication) and some of its organelles, and subsequently the partitioning of its cytoplasm, chromosomes and other components into two daughter cells in a process called cell division. In eukaryotic cells (having a cell nucleus) including animal, plant, fungal, and protist cells, the cell cycle is divided into two main stages: interphase, and the M phase that includes mitosis and cytokinesis. During interphase, the cell grows, accumulating nutrients needed for mitosis, and replicates its DNA and some of its organelles. During the M phase, the replicated Chromosome, chromosomes, organelles, and cytoplasm separate into two new daughter cells. To ensure the proper replication of cellular components and division, there are control mechanisms kno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Domain
In molecular biology, a protein domain is a region of a protein's Peptide, polypeptide chain that is self-stabilizing and that Protein folding, folds independently from the rest. Each domain forms a compact folded Protein tertiary structure, three-dimensional structure. Many proteins consist of several domains, and a domain may appear in a variety of different proteins. Molecular evolution uses domains as building blocks and these may be recombined in different arrangements to create proteins with different functions. In general, domains vary in length from between about 50 amino acids up to 250 amino acids in length. The shortest domains, such as zinc fingers, are stabilized by metal ions or Disulfide bond, disulfide bridges. Domains often form functional units, such as the calcium-binding EF-hand, EF hand domain of calmodulin. Because they are independently stable, domains can be "swapped" by genetic engineering between one protein and another to make chimera (protein), chimeric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nephronophthisis
Nephronophthisis is a genetic disorder of the kidneys which affects children. It is classified as a medullary cystic kidney disease. The disorder is inherited in an autosomal recessive In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the Phenotype, effect of a different variant of the same gene on Homologous chromosome, the other copy of the chromosome. The firs ... fashion and, although rare, is the most common genetic cause of childhood kidney failure. It is a form of ciliopathy. Its incidence has been estimated to be 0.9 cases per million people in the United States, and 1 in 50,000 births in Canada. Signs and symptoms Infantile, juvenile, and adolescent forms of nephronophthisis have been identified. Although the range of characterizations is broad, people affected by nephronophthisis typically present with polyuria (production of a large volume of urine), polydipsia (excessive liquid intake), and after sever ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meckel Syndrome
Meckel may refer to: People German anatomist/physician family Meckel * Johann Friedrich Meckel, the Younger (1781–1833), German anatomist * Johann Friedrich Meckel, the Elder (1724–1774) German anatomist, grandfather of the Younger * Philipp Friedrich Theodor Meckel (1755–1803) German anatomist, father of Johann Friedrich the Younger * August Albrecht Meckel (1789–1829) German physician. brother of Johann Friedrich the Younger * Johann Heinrich Meckel (1821–1856) German anatomist, son of Johann Friedrich the Younger Others * Christoph Meckel (1935–2020) German author and graphic artist * Jakob Meckel (1842–1905) Prussian general * Markus Meckel (born 1952) German theologian and politician * Miriam Meckel (born 1967) German journalist and academic Places * Meckel, Germany See also * {{disambiguation, surname German-language surnames ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cone Dystrophy
A cone dystrophy is an inherited ocular disorder characterized by the loss of cone cells, the photoreceptors responsible for both central and color vision. Presentation The most common symptoms of cone dystrophy are vision loss (age of onset ranging from the late teens to the sixties), sensitivity to bright lights, and poor color vision. Therefore, patients see better at dusk. Visual acuity usually deteriorates gradually, but it can deteriorate rapidly to 20/200; later, in more severe cases, it drops to "counting fingers" vision. Color vision testing using color test plates (HRR series) reveals many errors on both red-green and blue-yellow plates. Dystrophy of the rods and cones Dystrophy of the light-sensing cells of the eye may also occur in the rods as well, or in both the cones and the rods. A type of rod-cone dystrophy—where rod function decline is typically earlier or more pronounced than cone dystrophy—has been identified as a relatively common characteris ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joubert Syndrome
Joubert syndrome is a rare autosomal recessive genetic disorder that affects the cerebellum, an area of the Human brain, brain that controls balance and coordination. Joubert syndrome is one of the many genetic syndromes associated with syndromic retinitis pigmentosa. The syndrome was first identified in 1969 by pediatric neurologist Marie Joubert in Montreal, Quebec, Canada, while working at the Montreal Neurological Institute and McGill University. Signs and symptoms Most of the signs and symptoms of the Joubert syndrome appear very early in infancy with most children showing delays in gross motor milestones. Although other signs and symptoms vary widely from individual to individual, they generally fall under the hallmark of cerebellum involvement or in this case, lack thereof. Consequently, the most common features include ataxia (lack of muscle control), hyperpnea (abnormal breathing patterns), sleep apnea, abnormal eye and tongue movements, and hypotonia in early childhood ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orofaciodigital Syndrome 1
Orofaciodigital syndrome 1 (OFD1), also called Papillon-Léage and Psaume syndrome, is an X-linked congenital disorder characterized by malformations of the face, oral cavity, and digits with polycystic kidney disease and variable involvement of the central nervous system. Presentation Cause Orofaciodigital syndrome type 1 is caused by mutations in the OFD1 gene. OFD1 localizes to both centrosomes and basal bodies within the human genetic cellular structure. This suggests that this syndrome may fall into a broad category of ciliary diseases. The ciliary organelles are present in many cellular types throughout the human body. Cilia defects adversely affect numerous critical developmental signaling pathways essential to cellular development. Other types include: * * * * Relation to other rare genetic disorders Recent findings in genetic research have suggested that a large number of genetic disorders, both genetic syndromes and genetic diseases, that were not pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bardet–Biedl Syndrome
Bardet–Biedl syndrome (BBS) is a ciliopathic human genetic disorder that produces many effects and affects many body systems. It is characterized by rod/cone dystrophy, polydactyly, central obesity, hypogonadism, and kidney dysfunction in some cases. Historically, slower mental processing has also been considered a principal symptom but is now not regarded as such. Signs and symptoms Bardet–Biedl syndrome is a pleiotropic disorder with variable expressivity and a wide range of clinical variability observed both within and between families. The most common clinical features are rod–cone dystrophy, with childhood-onset night-blindness followed by increasing visual loss; postaxial polydactyly; truncal obesity that manifests during infancy and remains problematic throughout adulthood; varying degrees of learning disabilities; male hypogenitalism and complex female genitourinary malformations; and renal dysfunction, a major cause of morbidity and mortality. There ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deuterosome
In cell biology, a deuterosome is a protein structure within a multiciliated cell (such as an epithelial cell of respiratory tract) that produces multiple centrioles. Most cells in the human body possess one primary cilium, a relatively small protrusion of the cell membrane that looks like a stick or a finger under the electron microscope. Primary cilium is typically used by the cell as a sensory organelle, or antenna. Some cells, however, have numerous cilia which they use to generate directed fluid flow. Examples include: epithelial cells of the respiratory tract, in which multiple cilia are used for mucus clearance; the oviduct, in which cilia help the egg migrate to the uterus; and others. Each cilium has a basal body formed from a centriole to which it is anchored and from which it starts to grow after each cell division, when a new daughter cell is formed. Centrioles typically replicate once during cell division, thus allowing for only one cilium for a daughter cell. Mul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centrosome
In cell biology, the centrosome (Latin centrum 'center' + Greek sōma 'body') (archaically cytocentre) is an organelle that serves as the main microtubule organizing center (MTOC) of the animal cell, as well as a regulator of cell-cycle progression. The centrosome provides structure for the cell. It is thought to have evolved only in the metazoan lineage of eukaryotic cells. Fungi and plants lack centrosomes and therefore use other structures to organize their microtubules. Although the centrosome has a key role in efficient mitosis in animal cells, it is not essential in certain fly and flatworm species. Centrosomes are composed of two centrioles arranged at right angles to each other, and surrounded by a dense, highly structured mass of protein termed the pericentriolar material (PCM). The PCM contains proteins responsible for microtubule nucleation and anchoring — including γ-tubulin, pericentrin and ninein. In general, each centriole of the centrosome is based on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G1 Phase
The G1 phase, gap 1 phase, or growth 1 phase, is the first of four phases of the cell cycle that takes place in eukaryotic cell division. In this part of interphase, the cell synthesizes Messenger RNA, mRNA and proteins in preparation for subsequent steps leading to mitosis. G1 phase ends when the cell moves into the S phase of interphase. Around 30 to 40 percent of cell cycle time is spent in the G1 phase. Overview G1 phase together with the S phase and G2 phase, G2 phase comprise the long growth period of the cell cycle cell division called interphase that takes place before cell division in mitosis (M phase). During G1 phase, the cell grows in size and synthesizes mRNA and protein that are required for DNA synthesis. Once the required proteins and growth are complete, the cell enters the next phase of the cell cycle, S phase. The duration of each phase, including the G1 phase, is different in many different types of cells. In human somatic cells, the G1 stage of the cell c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
