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Nuclear Calcium
The concentration of calcium in the cell nucleus can increase in response to signals from the environment. Nuclear calcium is an evolutionary conserved potent regulator of gene expression that allows cells to undergo long-lasting adaptive responses. The 'Nuclear Calcium Hypothesis’ by Hilmar Bading describes nuclear calcium in neurons as an important signaling end-point in synapse-to-nucleus communication that activates gene expression programs needed for persistent adaptations. In the nervous system, nuclear calcium is required for long-term memory formation, acquired neuroprotection, and the development of chronic inflammatory pain. In the heart, nuclear calcium is important for the development of cardiac hypertrophy. In the immune system, nuclear calcium is required for human T cell activation. Plants use nuclear calcium to control symbiosis Symbiosis (from Greek , , "living together", from , , "together", and , bíōsis, "living") is any type of a close and long-term b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium
Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to its heavier homologues strontium and barium. It is the fifth most abundant element in Earth's crust, and the third most abundant metal, after iron and aluminium. The most common calcium compound on Earth is calcium carbonate, found in limestone and the fossilised remnants of early sea life; gypsum, anhydrite, fluorite, and apatite are also sources of calcium. The name derives from Latin ''calx'' "lime", which was obtained from heating limestone. Some calcium compounds were known to the ancients, though their chemistry was unknown until the seventeenth century. Pure calcium was isolated in 1808 via electrolysis of its oxide by Humphry Davy, who named the element. Calcium compounds are widely used in many industries: in foods and pharma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Nucleus
The cell nucleus (pl. nuclei; from Latin or , meaning ''kernel'' or ''seed'') is a membrane-bound organelle found in eukaryotic cells. Eukaryotic cells usually have a single nucleus, but a few cell types, such as mammalian red blood cells, have no nuclei, and a few others including osteoclasts have many. The main structures making up the nucleus are the nuclear envelope, a double membrane that encloses the entire organelle and isolates its contents from the cellular cytoplasm; and the nuclear matrix, a network within the nucleus that adds mechanical support. The cell nucleus contains nearly all of the cell's genome. Nuclear DNA is often organized into multiple chromosomes – long stands of DNA dotted with various proteins, such as histones, that protect and organize the DNA. The genes within these chromosomes are structured in such a way to promote cell function. The nucleus maintains the integrity of genes and controls the activities of the cell by regulating gene expres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene Expression
Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, protein or non-coding RNA, and ultimately affect a phenotype, as the final effect. These products are often proteins, but in non-protein-coding genes such as transfer RNA (tRNA) and small nuclear RNA (snRNA), the product is a functional non-coding RNA. Gene expression is summarized in the central dogma of molecular biology first formulated by Francis Crick in 1958, further developed in his 1970 article, and expanded by the subsequent discoveries of reverse transcription and RNA replication. The process of gene expression is used by all known life—eukaryotes (including multicellular organisms), prokaryotes (bacteria and archaea), and utilized by viruses—to generate the macromolecular machinery for life. In genetics, gene expression is the most fundamental level at which the genotype gives rise to the phenotype, '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synapse
In the nervous system, a synapse is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron or to the target effector cell. Synapses are essential to the transmission of nervous impulses from one neuron to another. Neurons are specialized to pass signals to individual target cells, and synapses are the means by which they do so. At a synapse, the plasma membrane of the signal-passing neuron (the ''presynaptic'' neuron) comes into close apposition with the membrane of the target (''postsynaptic'') cell. Both the presynaptic and postsynaptic sites contain extensive arrays of molecular machinery that link the two membranes together and carry out the signaling process. In many synapses, the presynaptic part is located on an axon and the postsynaptic part is located on a dendrite or soma. Astrocytes also exchange information with the synaptic neurons, responding to synaptic activity and, in turn, regulating neurotransmission. Syna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nervous System
In biology, the nervous system is the highly complex part of an animal that coordinates its actions and sensory information by transmitting signals to and from different parts of its body. The nervous system detects environmental changes that impact the body, then works in tandem with the endocrine system to respond to such events. Nervous tissue first arose in wormlike organisms about 550 to 600 million years ago. In vertebrates it consists of two main parts, the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS consists of the brain and spinal cord. The PNS consists mainly of nerves, which are enclosed bundles of the long fibers or axons, that connect the CNS to every other part of the body. Nerves that transmit signals from the brain are called motor nerves or '' efferent'' nerves, while those nerves that transmit information from the body to the CNS are called sensory nerves or '' afferent''. Spinal nerves are mixed nerves that serve both fu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long-term Memory
Long-term memory (LTM) is the stage of the Atkinson–Shiffrin memory model in which informative knowledge is held indefinitely. It is defined in contrast to short-term and working memory, which persist for only about 18 to 30 seconds. Long-term memory is commonly labelled as explicit memory ( declarative), as well as episodic memory, semantic memory, autobiographical memory, and implicit memory (procedural memory). Dual-store memory model According to Miller, whose paper in 1956 popularized the theory of the "magic number seven", short-term memory is limited to a certain number of chunks of information, while long-term memory has a limitless store. Atkinson–Shiffrin memory model According to the dual store memory model proposed by Richard C. Atkinson and Richard Shiffrin in 1968, memories can reside in the short-term "buffer" for a limited time while they are simultaneously strengthening their associations in long-term memory. When items are first presented, they enter sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acquired Neuroprotection
Acquired neuroprotection is a synaptic-activity-dependent form of adaptation in the nervous system that renders neurons more resistant to harmful conditions. The term was coined by Hilmar Bading. This use-dependent enhancement of cellular survival activity requires changes in gene expression triggered by neuronal activity and nuclear calcium signaling. In rodents, components of the neuroprotective gene program can reduce brain damage caused by seizure-like activity or by a stroke. In acute and chronic neurodegenerative diseases, gene regulatory events important for acquired neuroprotection are antagonized by extrasynaptic NMDA receptor Extrasynaptic NMDA receptors are glutamate-gated neurotransmitter receptors that are localized to non-synaptic sites on the neuronal cell surface. In contrast to synaptic NMDA receptors that promote acquired neuroprotection and synaptic plasticity, ... signaling leading to increased vulnerability, loss of structural integrity, and bioenergetics dysfun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypertrophy
Hypertrophy is the increase in the volume of an organ or tissue due to the enlargement of its component cells. It is distinguished from hyperplasia, in which the cells remain approximately the same size but increase in number.Updated by Linda J. Vorvick. 8/14/1Hyperplasia/ref> Although hypertrophy and hyperplasia are two distinct processes, they frequently occur together, such as in the case of the hormonally-induced proliferation and enlargement of the cells of the uterus during pregnancy. Eccentric hypertrophy is a type of hypertrophy where the walls and chamber of a hollow organ undergo growth in which the overall size and volume are enlarged. It is applied especially to the left ventricle of heart. Sarcomeres are added in series, as for example in dilated cardiomyopathy (in contrast to hypertrophic cardiomyopathy, a type of concentric hypertrophy, where sarcomeres are added in parallel). Gallery File:*+ * Photographic documentation on sexual education - Hypertrophy of bre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbiosis
Symbiosis (from Greek , , "living together", from , , "together", and , bíōsis, "living") is any type of a close and long-term biological interaction between two different biological organisms, be it mutualistic, commensalistic, or parasitic. The organisms, each termed a symbiont, must be of different species. In 1879, Heinrich Anton de Bary defined it as "the living together of unlike organisms". The term was subject to a century-long debate about whether it should specifically denote mutualism, as in lichens. Biologists have now abandoned that restriction. Symbiosis can be obligatory, which means that one or more of the symbionts depend on each other for survival, or facultative (optional), when they can generally live independently. Symbiosis is also classified by physical attachment. When symbionts form a single body it is called conjunctive symbiosis, while all other arrangements are called disjunctive symbiosis."symbiosis." Dorland's Illustrated Medical Dictionary. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuroscience
Neuroscience is the scientific study of the nervous system (the brain, spinal cord, and peripheral nervous system), its functions and disorders. It is a multidisciplinary science that combines physiology, anatomy, molecular biology, developmental biology, cytology, psychology, physics, computer science, chemistry, medicine, statistics, and Mathematical Modeling, mathematical modeling to understand the fundamental and emergent properties of neurons, glia and neural circuits. The understanding of the biological basis of learning, memory, behavior, perception, and consciousness has been described by Eric Kandel as the "epic challenge" of the Biology, biological sciences. The scope of neuroscience has broadened over time to include different approaches used to study the nervous system at different scales. The techniques used by neuroscientists have expanded enormously, from molecular biology, molecular and cell biology, cellular studies of individual neurons to neuroimaging, imaging ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene Expression
Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, protein or non-coding RNA, and ultimately affect a phenotype, as the final effect. These products are often proteins, but in non-protein-coding genes such as transfer RNA (tRNA) and small nuclear RNA (snRNA), the product is a functional non-coding RNA. Gene expression is summarized in the central dogma of molecular biology first formulated by Francis Crick in 1958, further developed in his 1970 article, and expanded by the subsequent discoveries of reverse transcription and RNA replication. The process of gene expression is used by all known life—eukaryotes (including multicellular organisms), prokaryotes (bacteria and archaea), and utilized by viruses—to generate the macromolecular machinery for life. In genetics, gene expression is the most fundamental level at which the genotype gives rise to the phenotype, '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
