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Ankyrin
Ankyrins are a family of proteins that mediate the attachment of integral membrane proteins to the spectrin-actin based membrane cytoskeleton. Ankyrins have binding sites for the beta subunit of spectrin and at least 12 families of integral membrane proteins. This linkage is required to maintain the integrity of the plasma membranes and to anchor specific ion channels, ion exchangers and ion transporters in the plasma membrane. The name is derived from the Greek language, Greek word wikt:ἄγκυρα, ἄγκυρα (''ankyra'') for "anchor". Structure Ankyrins contain four functional Structural domain, domains: an N-terminal domain that contains 24 tandem ankyrin repeats, a central domain that binds to spectrin, a death domain that binds to proteins involved in apoptosis, and a C-terminal regulatory domain that is highly variable between different ankyrin proteins. Membrane protein recognition The 24 tandem ankyrin repeats are responsible for the recognition of a wide range of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ANK2
Ankyrin-2, also known as Ankyrin-B, and Brain ankyrin, is a protein which in humans is encoded by the ''ANK2'' gene. Ankyrin-2 is ubiquitously expressed, but shows high expression in cardiac muscle. Ankyrin-2 plays an essential role in the localization and membrane stabilization of ion transporters and ion channels in cardiomyocytes, as well as in costamere structures. Mutations in ''ANK2'' cause a dominantly-inherited, cardiac Heart arrhythmia, arrhythmia syndrome known as Long QT syndrome, long QT syndrome 4 as well as sick sinus syndrome; mutations have also been associated to a lesser degree with hypertrophic cardiomyopathy. Alterations in ankyrin-2 expression levels are observed in human heart failure. Structure Ankyrin-B protein is around 220 kDa, with several isoforms. The ''ANK2'' gene is approximately 560 kb in size and consists of 53 exons on human chromosome 4; ''ANK2'' is also transcriptionally regulated via over 30 alternative splicing events with variable expression ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ANK3
Ankyrin-3 (ANK-3), also known as ankyrin-G, is a protein from ankyrin family that in humans is encoded by the ''ANK3'' gene. Function The protein encoded by this gene, ankyrin-3 is an immunologically distinct gene product from ankyrins ANK1 and ANK2, and was originally found at the axonal initial segment and nodes of Ranvier of neurons in the central and peripheral nervous systems. Alternatively spliced variants may be expressed in other tissues. Although multiple transcript variants encoding several different isoforms have been found for this gene, the full-length nature of only two have been characterized. Within the nervous system, ankyrin-G is specifically localized to the neuromuscular junction, the axon initial segment and the Nodes of Ranvier. Within the nodes of Ranvier where action potentials are actively propagated, ankyrin-G has long been thought to be the intermediate binding partner to neurofascin and voltage-gated sodium channels. The genetic deletion of ankyr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ankyrin Repeat
The ankyrin repeat is a 33-residue motif in proteins consisting of two alpha helices separated by loops, first discovered in signaling proteins in yeast Cdc10 and '' Drosophila'' Notch. Domains consisting of ankyrin tandem repeats mediate protein–protein interactions and are among the most common structural motifs in known proteins. They appear in bacterial, archaeal, and eukaryotic proteins, but are far more common in eukaryotes. Ankyrin repeat proteins, though absent in most viruses, are common among poxviruses. Most proteins that contain the motif have four to six repeats, although its namesake ankyrin contains 24, and the largest known number of repeats is 34, predicted in a protein expressed by '' Giardia lamblia''. Ankyrin repeats typically fold together to form a single, linear solenoid structure called ankyrin repeat domains. These domains are one of the most common protein–protein interaction platforms in nature. They occur in a large number of functionall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ANK1
Ankyrin 1, also known as ANK-1, and erythrocyte ankyrin, is a protein that in humans is encoded by the ''ANK1'' gene. Tissue distribution The protein encoded by this gene, Ankyrin 1, is the prototype of the ankyrin family, was first discovered in erythrocytes, but since has also been found in brain and muscles. Genetics Complex patterns of alternative splicing in the regulatory domain, giving rise to different isoforms of ankyrin 1 have been described, however, the precise functions of the various isoforms are not known. Alternative polyadenylation accounting for the different sized erythrocytic ankyrin 1 mRNAs, has also been reported. Truncated muscle-specific isoforms of ankyrin 1 resulting from usage of an alternate promoter have also been identified. Disease linkage Mutations in erythrocytic ankyrin 1 have been associated in approximately half of all patients with hereditary spherocytosis. ANK1 shows altered methylation and expression in Alzheimer's disease. A gene expr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hereditary Spherocytosis
Hereditary spherocytosis (HS) is a congenital hemolytic disorder wherein a genetic genetic mutation, mutation coding for a structural membrane protein phenotype causes the red blood cells to be sphere-shaped (spherocytosis), rather than the normal biconcave disk shape. This abnormal shape interferes with the cells' ability to flex during blood circulation, and also makes them more prone to hemolysis, rupture under osmotic stress, mechanical stress, or both. Cells with the dysfunctional proteins are degraded in the spleen, which leads to a shortage of erythrocytes and results in hemolytic anemia. HS was first described in 1871, and is the most common cause of inherited hemolysis in populations of northern European descent, with an incidence of 1 in 5000 births. The clinical severity of HS varies from mild (symptom-free carrier), to moderate (anemic, jaundiced, and with splenomegaly), to severe (hemolytic crisis, in-utero hydrops fetalis), because HS is caused by genetic mutations i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KAHRP
KAHRP (knob-associated histidine-rich protein) is a protein expressed by ''Plasmodium falciparum'' infecting erythrocytes. KAHRP is a major component of knobs, feature found on Plasmodium falciparum infected erythrocytes. It has been suggested that KAHRP may play a role in trafficking or docking PfEMP1, major malarial cytoadherence protein to the erythrocyte membrane; however, these findings were disputed by recent NMR and fluorescence anisotropy studies showing no interaction between PfEMP1 and KAHRP. Instead, KAHRP was shown to interact with Ankyrin, more precisely the D3 subunit of the Membrane-binding domain of Ankyrin type 1. This interaction was suggested via SPR, ELISA, and Pulldown studies, however, it has not been confirmed by NMR, ITC, crystallography Crystallography is the branch of science devoted to the study of molecular and crystalline structure and properties. The word ''crystallography'' is derived from the Ancient Greek word (; "clear ice, rock-crys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DARPin
DARPins (an acronym for designed ankyrin repeat proteins) are genetically engineered antibody mimetic proteins typically exhibiting highly specific and high-affinity target protein binding. They are derived from natural ankyrin repeat proteins, one of the most common classes of binding proteins in nature, which are responsible for diverse functions such as cell signaling, regulation and structural integrity of the cell. DARPins consist of at least three repeat motifs or modules, of which the most N- and the most C-terminal modules are referred to as "caps", since they shield the hydrophobic core of the protein. The number of internal modules is indicated as number (e.g. N1C, N2C, N3C, ...) while the caps are indicated with "N" or "C", respectively. The molecular mass of e.g. 14 or 18 kDa (kilodaltons) for four- (N2C) or five- (N3C) repeat DARPins is rather small for a biologic (ca 10% of the size of an IgG). DARPins constitute a new class of potent, specific and versatile smal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasma Membrane
The cell membrane (also known as the plasma membrane or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of a cell from the outside environment (the extracellular space). The cell membrane consists of a lipid bilayer, made up of two layers of phospholipids with cholesterols (a lipid component) interspersed between them, maintaining appropriate membrane fluidity at various temperatures. The membrane also contains membrane proteins, including integral proteins that span the membrane and serve as membrane transporters, and peripheral proteins that loosely attach to the outer (peripheral) side of the cell membrane, acting as enzymes to facilitate interaction with the cell's environment. Glycolipids embedded in the outer lipid layer serve a similar purpose. The cell membrane controls the movement of substances in and out of a cell, being selectively permeable to ions and organic molecu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemolytic Anemia
Hemolytic anemia or haemolytic anaemia is a form of anemia due to hemolysis, the abnormal breakdown of red blood cells (RBCs), either in the blood vessels (intravascular hemolysis) or elsewhere in the human body (extravascular). This most commonly occurs within the spleen, but also can occur in the reticuloendothelial system or mechanically (prosthetic valve damage). Hemolytic anemia accounts for 5% of all existing anemias. It has numerous possible consequences, ranging from general symptoms to life-threatening systemic effects. The general classification of hemolytic anemia is either intrinsic or extrinsic. Treatment depends on the type and cause of the hemolytic anemia. Symptoms of hemolytic anemia are similar to other forms of anemia (fatigue and shortness of breath), but in addition, the breakdown of red cells leads to jaundice and increases the risk of particular long-term complications, such as gallstones and pulmonary hypertension. Signs and symptoms Symptoms of hemolytic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bipolar Disorder
Bipolar disorder (BD), previously known as manic depression, is a mental disorder characterized by periods of Depression (mood), depression and periods of abnormally elevated Mood (psychology), mood that each last from days to weeks, and in some cases months. If the elevated mood is severe or associated with psychosis, it is called ''mania''; if it is less severe and does not significantly affect functioning, it is called ''hypomania''. During mania, an individual behaves or feels abnormally energetic, happy, or irritable, and they often make impulsive decisions with little regard for the consequences. There is usually, but not always, a Sleep deprivation, reduced need for sleep during manic phases. During periods of depression, the individual may experience crying, have a negative outlook on life, and demonstrate poor eye contact with others. The risk of suicide is high. Over a period of 20 years, 6% of those with bipolar disorder died by suicide, with about one-third Suicide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ELISA
The enzyme-linked immunosorbent assay (ELISA) (, ) is a commonly used analytical biochemistry assay, first described by Eva Engvall and Peter Perlmann in 1971. The assay is a solid-phase type of enzyme immunoassay (EIA) to detect the presence of a ligand (commonly an amino acid) in a liquid sample using antibodies directed against the ligand to be measured. ELISA has been used as a medical diagnosis, diagnostic tool in medicine, plant pathology, and biotechnology, as well as a quality control check in various industries. In the most simple form of an ELISA, antigens from the sample to be tested are attached to a surface. Then, a matching antibody is applied over the surface so it can bind the antigen. This antibody is linked to an enzyme, and then any unbound antibodies are removed. In the final step, a substance containing the enzyme's Enzyme substrate, substrate is added. If there was binding, the subsequent reaction produces a detectable signal, most commonly a color change. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
