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Ataxin 1
Ataxin-1 is a DNA-binding protein which in humans is encoded by the ''ATXN1'' gene. Mutations in ataxin-1 cause spinocerebellar ataxia type 1, an inherited Neurodegeneration, neurodegenerative disease characterized by a progressive loss of cerebellar neurons, particularly Purkinje cell, Purkinje neurons. Genetics ''ATXN1'' is conserved across multiple species, including humans, mice, and ''Drosophila.'' In humans, ''ATXN1'' is located on the short arm of Chromosome 6 (human), chromosome 6. The gene contains 9 Exon, exons, two of which are protein-coding. There is a CAG repeat in the coding sequence which is longer in humans than other species (6-38 uninterrupted CAG repeats in healthy humans versus 2 in the mouse gene). This repeat is prone to errors in DNA replication and can vary widely in length between individuals. Structure Notable features of the Ataxin-1 protein structure include: * A polyglutamine tract of variable length, encoded by the CAG repeat in ''ATXN1.'' * A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid residue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CIC (gene)
Capicua transcriptional repressor is a protein that in humans is encoded by the ''CIC'' gene. Capicua functions as a transcriptional repressor in a way that ensures its impact on the progression of cancer, and plays a significant role in the operation of the central nervous system through its interaction with ataxin 1. The name of the protein derives from the Catalan expression ''cap-i-cua'' which literally translates to "head-and-tail". Structure Capicua is a highly conserved protein, with a lot of similarity between human and Drosophila melanogaster. In the human body, capicua exists in two isoforms, the short (CIC-S) and the long (CIC-L) one, which differ in their N-terminal section. The two evolutionarily conserved domains of the protein are HMG-box (high-mobility group box) and the C1 domain: they work together to recognize specific octameric DNA sequences. Capicua also contains a nuclear localisation sequence that allows it to enter the nucleus of the cell. Clinical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondrion
A mitochondrion (; ) is an organelle found in the cells of most Eukaryotes, such as animals, plants and fungi. Mitochondria have a double membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is used throughout the cell as a source of chemical energy. They were discovered by Albert von Kölliker in 1857 in the voluntary muscles of insects. The term ''mitochondrion'' was coined by Carl Benda in 1898. The mitochondrion is popularly nicknamed the "powerhouse of the cell", a phrase coined by Philip Siekevitz in a 1957 article of the same name. Some cells in some multicellular organisms lack mitochondria (for example, mature mammalian red blood cells). A large number of unicellular organisms, such as microsporidia, parabasalids and diplomonads, have reduced or transformed their mitochondria into other structures. One eukaryote, ''Monocercomonoides'', is known to have completely lost its mitochondria, and one multicellular organism, '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuron
A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. Non-animals like plants and fungi do not have nerve cells. Neurons are typically classified into three types based on their function. Sensory neurons respond to stimuli such as touch, sound, or light that affect the cells of the sensory organs, and they send signals to the spinal cord or brain. Motor neurons receive signals from the brain and spinal cord to control everything from muscle contractions to glandular output. Interneurons connect neurons to other neurons within the same region of the brain or spinal cord. When multiple neurons are connected together, they form what is called a neural circuit. A typical neuron consists of a cell body (soma), dendrites, and a single axon. The soma is a compact structure, and the axon and dend ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurodegeneration
A neurodegenerative disease is caused by the progressive loss of structure or function of neurons, in the process known as neurodegeneration. Such neuronal damage may ultimately involve cell death. Neurodegenerative diseases include amyotrophic lateral sclerosis, multiple sclerosis, Parkinson's disease, Alzheimer's disease, Huntington's disease, multiple system atrophy, and prion diseases. Neurodegeneration can be found in the brain at many different levels of neuronal circuitry, ranging from molecular to systemic. Because there is no known way to reverse the progressive degeneration of neurons, these diseases are considered to be incurable; however research has shown that the two major contributing factors to neurodegeneration are oxidative stress and inflammation. Biomedical research has revealed many similarities between these diseases at the subcellular level, including atypical protein assemblies (like proteinopathy) and induced cell death. These similarities suggest that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HMGB1
High mobility group box 1 protein, also known as high-mobility group protein 1 (HMG-1) and amphoterin, is a protein that in humans is encoded by the ''HMGB1'' gene. HMG-1 belongs to the high mobility group and contains a HMG-box domain. Function Like the histones, HMGB1 is among the most important chromatin proteins. In the nucleus HMGB1 interacts with nucleosomes, transcription factors, and histones. This nuclear protein organizes the DNA and regulates transcription. After binding, HMGB1 bends DNA, which facilitates the binding of other proteins. HMGB1 supports transcription of many genes in interactions with many transcription factors. It also interacts with nucleosomes to loosen packed DNA and remodel the chromatin. Contact with core histones changes the structure of nucleosomes. The presence of HMGB1 in the nucleus depends on posttranslational modifications. When the protein is not acetylated, it stays in the nucleus, but hyperacetylation on lysine residues causes it to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Huntingtin
Huntingtin (Htt) is the protein coded for in humans by the ''HTT'' gene, also known as the ''IT15'' ("interesting transcript 15") gene. Mutated ''HTT'' is the cause of Huntington's disease (HD), and has been investigated for this role and also for its involvement in long-term memory storage. It is variable in its structure, as the many polymorphisms of the gene can lead to variable numbers of glutamine residues present in the protein. In its wild-type (normal form), it contains 6-35 glutamine residues. However, in individuals affected by Huntington's disease (an autosomal dominant genetic disorder), it contains more than 36 glutamine residues (highest reported repeat length is about 250). Its commonly used name is derived from this disease; previously, the ''IT15'' label was commonly used. The mass of huntingtin protein is dependent largely on the number of glutamine residues it has; the predicted mass is around 350 kDa. Normal huntingtin is generally accepted to be 3144 am ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amyloid Beta
Amyloid beta (Aβ or Abeta) denotes peptides of 36–43 amino acids that are the main component of the amyloid plaques found in the brains of people with Alzheimer's disease. The peptides derive from the amyloid precursor protein (APP), which is cleaved by beta secretase and gamma secretase to yield Aβ in a cholesterol-dependent process and substrate presentation. Aβ molecules can aggregate to form flexible soluble oligomers which may exist in several forms. It is now believed that certain misfolded oligomers (known as "seeds") can induce other Aβ molecules to also take the misfolded oligomeric form, leading to a chain reaction akin to a prion infection. The oligomers are toxic to nerve cells. The other protein implicated in Alzheimer's disease, tau protein, also forms such prion-like misfolded oligomers, and there is some evidence that misfolded Aβ can induce tau to misfold. A study has suggested that APP and its amyloid potential is of ancient origins, dating as far back a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tau Protein
The tau proteins (abbreviated from tubulin associated unit) are a group of six highly soluble protein isoforms produced by alternative splicing from the gene ''MAPT'' (microtubule-associated protein tau). They have roles primarily in maintaining the stability of microtubules in axons and are abundant in the neurons of the central nervous system (CNS), where the cerebral cortex has the highest abundance. They are less common elsewhere but are also expressed at very low levels in CNS astrocytes and oligodendrocytes. Pathologies and dementias of the nervous system such as Alzheimer's disease and Parkinson's disease are associated with tau proteins that have become hyperphosphorylated insoluble aggregates called neurofibrillary tangles. The tau proteins were identified in 1975 as heat-stable proteins essential for microtubule assembly, and since then they have been characterized as intrinsically disordered proteins. Function Microtubule stabilization Tau proteins are found mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trinucleotide Repeat Disorder
Trinucleotide repeat disorders, also known as microsatellite expansion diseases, are a set of over 50 genetic disorders caused by trinucleotide repeat expansion, a kind of mutation in which repeats of three nucleotides ( trinucleotide repeats) increase in copy numbers until they cross a threshold above which they become unstable. Depending on its location, the unstable trinucleotide repeat may cause defects in a protein encoded by a gene; change the regulation of gene expression; produce a toxic RNA, or lead to chromosome instability. In general, the larger the expansion the faster the onset of disease, and the more severe the disease becomes. Trinucleotide repeats are a subset of a larger class of unstable microsatellite repeats that occur throughout all genomes. The first trinucleotide repeat disease to be identified was fragile X syndrome, which has since been mapped to the long arm of the X chromosome. Patients carry from 230 to 4000 CGG repeats in the gene that causes fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brainstem
The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is continuous with the thalamus of the diencephalon through the tentorial notch, and sometimes the diencephalon is included in the brainstem. The brainstem is very small, making up around only 2.6 percent of the brain's total weight. It has the critical roles of regulating cardiac, and respiratory function, helping to control heart rate and breathing rate. It also provides the main motor and sensory nerve supply to the face and neck via the cranial nerves. Ten pairs of cranial nerves come from the brainstem. Other roles include the regulation of the central nervous system and the body's sleep cycle. It is also of prime importance in the conveyance of motor and sensory pathways from the rest of the brain to the body, and from the body back to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebellum
The cerebellum (Latin for "little brain") is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as or even larger. In humans, the cerebellum plays an important role in motor control. It may also be involved in some cognition, cognitive functions such as attention and language as well as emotion, emotional control such as regulating fear and pleasure responses, but its movement-related functions are the most solidly established. The human cerebellum does not initiate movement, but contributes to Motor coordination, coordination, precision, and accurate timing: it receives input from sensory systems of the spinal cord and from other parts of the brain, and integrates these inputs to fine-tune motor activity. Cerebellar damage produces disorders in Fine motor skill, fine movement, Equilibrioception, equilibrium, Human positions, posture, and motor learning in humans. Anatomica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
