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Ciona Intestinalis
''Ciona intestinalis'' (sometimes known by the common name of vase tunicate) is an ascidian (sea squirt), a tunicate with very soft tunic. Its Latin name literally means "pillar of intestines", referring to the fact that its body is a soft, translucent column-like structure, resembling a mass of intestines sprouting from a rock. It is a globally distributed cosmopolitan species. Since Linnaeus described the species, ''Ciona intestinalis'' has been used as a model invertebrate chordate in developmental biology and genomics. Studies conducted between 2005 and 2010 have shown that there are at least two, possibly four, sister species. More recently it has been shown that one of these species has already been described as '' Ciona robusta''. By anthropogenic means, the species has invaded various parts of the world and is known as an invasive species. Although Linnaeus first categorised this species as a kind of mollusk, Alexander Kovalevsky found a tadpole-like larval stage during ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascidiacea
Ascidiacea, commonly known as the ascidians, tunicates (in part), and sea squirts (in part), is a polyphyletic class in the subphylum Tunicata of sac-like marine invertebrate filter feeders. Ascidians are characterized by a tough outer "tunic" made of a polysaccharide. Ascidians are found all over the world, usually in shallow water with salinities over 2.5%. While members of the Thaliacea and Larvacea (Appendicularia) swim freely like plankton, sea squirts are sessile animals after their larval phase: they then remain firmly attached to their substratum, such as rocks and shells. There are 2,300 species of ascidians and three main types: solitary ascidians, social ascidians that form clumped communities by attaching at their bases, and compound ascidians that consist of many small individuals (each individual is called a zooid) forming colonies up to several meters in diameter. Sea squirts feed by taking in water through a tube, the oral siphon. The water enters the mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Axon Terminal
Axon terminals (also called synaptic boutons, terminal boutons, or end-feet) are distal terminations of the telodendria (branches) of an axon. An axon, also called a nerve fiber, is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses called action potentials away from the neuron's cell body, or soma, in order to transmit those impulses to other neurons, muscle cells or glands. Neurons are interconnected in complex arrangements, and use electrochemical signals and neurotransmitter chemicals to transmit impulses from one neuron to the next; axon terminals are separated from neighboring neurons by a small gap called a synapse, across which impulses are sent. The axon terminal, and the neuron from which it comes, is sometimes referred to as the "presynaptic" neuron. Nerve impulse release Neurotransmitters are packaged into synaptic vesicles that cluster beneath the axon terminal membrane on the presynaptic side of a synapse. The axonal terminals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chordate
A chordate () is an animal of the phylum Chordata (). All chordates possess, at some point during their larval or adult stages, five synapomorphies, or primary physical characteristics, that distinguish them from all the other taxa. These five synapomorphies include a notochord, dorsal hollow nerve cord, endostyle or thyroid, pharyngeal slits, and a post-anal tail. The name “chordate” comes from the first of these synapomorphies, the notochord, which plays a significant role in chordate structure and movement. Chordates are also bilaterally symmetric, have a coelom, possess a circulatory system, and exhibit metameric segmentation. In addition to the morphological characteristics used to define chordates, analysis of genome sequences has identified two conserved signature indels (CSIs) in their proteins: cyclophilin-like protein and mitochondrial inner membrane protease ATP23, which are exclusively shared by all vertebrates, tunicates and cephalochordates. These ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebrate
Vertebrates () comprise all animal taxa within the subphylum Vertebrata () (chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, with currently about 69,963 species described. Vertebrates comprise such groups as the following: * jawless fish, which include hagfish and lampreys * jawed vertebrates, which include: ** cartilaginous fish (sharks, rays, and ratfish) ** bony vertebrates, which include: *** ray-fins (the majority of living bony fish) *** lobe-fins, which include: **** coelacanths and lungfish **** tetrapods (limbed vertebrates) Extant vertebrates range in size from the frog species ''Paedophryne amauensis'', at as little as , to the blue whale, at up to . Vertebrates make up less than five percent of all described animal species; the rest are invertebrates, which lack vertebral columns. The vertebrates traditionally include the hagfish, which do not have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transferrin
Transferrins are glycoproteins found in vertebrates which bind to and consequently mediate the transport of iron (Fe) through blood plasma. They are produced in the liver and contain binding sites for two Fe3+ ions. Human transferrin is encoded by the ''TF'' gene and produced as a 76 kDa glycoprotein. Transferrin glycoproteins bind iron tightly, but reversibly. Although iron bound to transferrin is less than 0.1% (4 mg) of total body iron, it forms the most vital iron pool with the highest rate of turnover (25 mg/24 h). Transferrin has a molecular weight of around 80 kDa and contains two specific high-affinity Fe(III) binding sites. The affinity of transferrin for Fe(III) is extremely high (association constant is 1020 M−1 at pH 7.4) but decreases progressively with decreasing pH below neutrality. Transferrins are not limited to only binding to iron but also to different metal ions. These glycoproteins are located in various bodily fluids of vertebrates. Some inv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetically Encoded Voltage Indicator
Genetically encoded voltage indicator (or GEVI) is a protein that can sense membrane potential in a cell and relate the change in voltage to a form of output, often fluorescent level. It is a promising optogenetic recording tool that enables exporting electrophysiological signals from cultured cells, live animals, and ultimately human brain. Examples of notable GEVIs include ArcLight, ASAP1, ASAP3, Archons, SomArchon, and Ace2N-mNeon. History Despite that the idea of optical measurement of neuronal activity was proposed in the late 1960s, the first successful GEVI that was convenient enough to put into actual use was not developed until technologies of genetic engineering had become mature in the late 1990s. The first GEVI, coined FlaSh, was constructed by fusing a modified green fluorescent protein with a voltage-sensitive K+ channel ( Shaker). Unlike fluorescent proteins, the discovery of new GEVIs were seldom inspired by the nature, for it is hard to find an organism which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ciona Savignyi
''Ciona savignyi'' is a marine animal sometimes known as the Pacific transparent sea squirt or solitary sea squirt. It is a species of tunicates in the family Cionidae. It is found in shallow waters around Japan and has spread to the west coast of North America where it is regarded as an invasive species. Description ''Ciona savignyi'' is a solitary, bottle or vase-shaped tunicate growing to a length of about . It is usually broader near the base and this part is permanently attached to a hard surface. The outer covering or tunic is soft and gelatinous, translucent, whitish or cream-coloured. The muscle bands and internal organs can often be seen through the tunic. At the narrower, free end, there is a buccal siphon through which water is drawn into the animal. This opening is rimmed by eight yellow-edged lobes each with an orange-red spot. At the side, not far from the buccal siphon, there is an atrial siphon out of which water is pumped. This has six similar yellow lobes with r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hox Gene
Hox genes, a subset of homeobox genes, are a group of related genes that specify regions of the body plan of an embryo along the head-tail axis of animals. Hox proteins encode and specify the characteristics of 'position', ensuring that the correct structures form in the correct places of the body. For example, Hox genes in insects specify which appendages form on a segment (for example, legs, antennae, and wings in fruit flies), and Hox genes in vertebrates specify the types and shape of vertebrae that will form. In segmented animals, Hox proteins thus confer segmental or positional identity, but do not form the actual segments themselves. Studies on Hox genes in ciliated larvae have shown they are only expressed in future adult tissues. In larvae with gradual metamorphosis the Hox genes are activated in tissues of the larval body, generally in the trunk region, that will be maintained through metamorphosis. In larvae with complete metamorphosis the Hox genes are mainly express ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome
A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are the histones. These proteins, aided by chaperone proteins, bind to and condense the DNA molecule to maintain its integrity. These chromosomes display a complex three-dimensional structure, which plays a significant role in transcriptional regulation. Chromosomes are normally visible under a light microscope only during the metaphase of cell division (where all chromosomes are aligned in the center of the cell in their condensed form). Before this happens, each chromosome is duplicated ( S phase), and both copies are joined by a centromere, resulting either in an X-shaped structure (pictured above), if the centromere is located equatorially, or a two-arm structure, if the centromere is located distally. The joined copies are now c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base Pair
A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA and RNA. Dictated by specific hydrogen bonding patterns, "Watson–Crick" (or "Watson–Crick–Franklin") base pairs (guanine–cytosine and adenine–thymine) allow the DNA helix to maintain a regular helical structure that is subtly dependent on its nucleotide sequence. The complementary nature of this based-paired structure provides a redundant copy of the genetic information encoded within each strand of DNA. The regular structure and data redundancy provided by the DNA double helix make DNA well suited to the storage of genetic information, while base-pairing between DNA and incoming nucleotides provides the mechanism through which DNA polymerase replicates DNA and RNA polymerase transcribes DNA into RNA. Many DNA-binding prot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Full Genome Sequencing
Whole genome sequencing (WGS), also known as full genome sequencing, complete genome sequencing, or entire genome sequencing, is the process of determining the entirety, or nearly the entirety, of the DNA sequence of an organism's genome at a single time. This entails sequencing all of an organism's chromosomal DNA as well as DNA contained in the mitochondria and, for plants, in the chloroplast. Whole genome sequencing has largely been used as a research tool, but was being introduced to clinics in 2014. In the future of personalized medicine, whole genome sequence data may be an important tool to guide therapeutic intervention. The tool of gene sequencing at SNP level is also used to pinpoint functional variants from association studies and improve the knowledge available to researchers interested in evolutionary biology, and hence may lay the foundation for predicting disease susceptibility and drug response. Whole genome sequencing should not be confused with DNA pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Signaling
In biology, cell signaling (cell signalling in British English) or cell communication is the ability of a cell to receive, process, and transmit signals with its environment and with itself. Cell signaling is a fundamental property of all cellular life in prokaryotes and eukaryotes. Signals that originate from outside a cell (or extracellular signals) can be physical agents like mechanical pressure, voltage, temperature, light, or chemical signals (e.g., small molecules, peptides, or gas). Cell signaling can occur over short or long distances, and as a result can be classified as autocrine, juxtacrine, intracrine, paracrine, or endocrine. Signaling molecules can be synthesized from various biosynthetic pathways and released through passive or active transports, or even from cell damage. Receptors play a key role in cell signaling as they are able to detect chemical signals or physical stimuli. Receptors are generally proteins located on the cell surface or within the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
