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Ankyrin Repeats
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 word ἄγκυρα (''ankyra'') for "anchor". Structure Ankyrins contain four functional 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 membrane proteins. These 24 repeats contain 3 struc ... [...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] |
C-terminal
The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, carboxy tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein or polypeptide), terminated by a free carboxyl group (-COOH). When the protein is translated from messenger RNA, it is created from N-terminus to C-terminus. The convention for writing peptide sequences is to put the C-terminal end on the right and write the sequence from N- to C-terminus. Chemistry Each amino acid has a carboxyl group and an amine group. Amino acids link to one another to form a chain by a dehydration reaction which joins the amine group of one amino acid to the carboxyl group of the next. Thus polypeptide chains have an end with an unbound carboxyl group, the C-terminus, and an end with an unbound amine group, the N-terminus. Proteins are naturally synthesized starting from the N-terminus and ending at the C-terminus. Function C-terminal retention signals While the N-terminus of a prote ... [...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] |
Surface Plasmon Resonance
Surface plasmon resonance (SPR) is a phenomenon that occurs where electrons in a thin metal sheet become excited by light that is directed to the sheet with a particular angle of incidence (optics), angle of incidence, and then travel parallel to the sheet. Assuming a constant light source wavelength and that the metal sheet is thin, the angle of incidence that triggers SPR is related to the refractive index of the material and even a small change in the refractive index will cause SPR to not be observed. This makes SPR a possible technique for detecting particular substances (analytes) and SPR biosensors have been developed to detect various important biomarkers. Explanation The surface plasmon polariton is a non-radiative Surface wave#Electromagnetic waves, electromagnetic surface wave that propagates in a direction parallel to the negative permittivity/dielectric material interface. Since the wave is on the boundary of the conductor and the external medium (air, water or vacuu ... [...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] |
Cytoskeleton
The cytoskeleton is a complex, dynamic network of interlinking protein filaments present in the cytoplasm of all cells, including those of bacteria and archaea. In eukaryotes, it extends from the cell nucleus to the cell membrane and is composed of similar proteins in the various organisms. It is composed of three main components: microfilaments, intermediate filaments, and microtubules, and these are all capable of rapid growth and or disassembly depending on the cell's requirements. Cytoskeleton can perform many functions. Its primary function is to give the cell its shape and mechanical resistance to deformation, and through association with extracellular connective tissue and other cells it stabilizes entire tissues. The cytoskeleton can also contract, thereby deforming the cell and the cell's environment and allowing cells to migrate. Moreover, it is involved in many cell signaling pathways and in the uptake of extracellular material ( endocytosis), the segregation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inositol Triphosphate Receptor
Inositol trisphosphate receptor (InsP3R) is a membrane glycoprotein complex acting as a calcium channel, Ca2+ channel activated by inositol trisphosphate (InsP3). InsP3R is very diverse among organisms, and is necessary for the control of cellular and physiological processes including cell division, cell proliferation, apoptosis, fertilization, development, behavior, learning and memory. Inositol triphosphate receptor represents a dominant second messenger leading to the release of Ca2+ from intracellular store sites. There is strong evidence suggesting that the InsP3R plays an important role in the conversion of external stimuli to intracellular Ca2+ signals characterized by complex patterns relative to both space and time, such as Ca2+ waves and oscillations. Discovery The InsP3 receptor was first purified from rat cerebellum by neuroscientists Surachai Supattapone and Solomon Snyder at Johns Hopkins University School of Medicine. The cDNA of the InsP3 receptor was first cl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CD44
The CD44 antigen is a cell-surface glycoprotein involved in cell–cell interactions, cell adhesion and migration. In humans, the CD44 antigen is encoded by the ''CD44'' gene on chromosome 11. CD44 has been referred to as HCAM (homing cell adhesion molecule), Pgp-1 (phagocytic glycoprotein-1), Hermes antigen, lymphocyte homing receptor, ECM-III, and HUTCH-1. Tissue distribution and isoforms CD44 is expressed in a large number of mammalian cell types. The standard isoform, designated CD44s, comprising exons 1–5 and 16–20 is expressed in most cell types. CD44 splice variants containing variable exons are designated CD44v. Some epithelial cells also express a larger isoform (CD44E), which includes exons v8–10. Function CD44 participates in a wide variety of cellular functions including lymphocyte activation, recirculation and homing, hematopoiesis, and tumor metastasis. CD44 is a receptor for hyaluronic acid and internalizes metals bound to hyaluronic acid and can a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Band 3
Band 3 anion transport protein, also known as anion exchanger 1 (AE1) or band 3 or solute carrier family 4 member 1 (SLC4A1), is a protein that is encoded by the gene in humans. Band 3 anion transport protein is a phylogenetically-preserved transport protein responsible for mediating the exchange of chloride (Cl−) with bicarbonate (HCO3−) across plasma membranes. Functionally similar members of the AE clade are AE2 and AE3. Function Band 3 is present in the basolateral face of the α-intercalated cells of the collecting ducts of the nephron, which are the main acid-secreting cells of the kidney. They generate hydrogen ions and bicarbonate ions from carbon dioxide and water – a reaction catalysed by carbonic anhydrase. The hydrogen ions are pumped into the collecting duct tubule by vacuolar H+ ATPase, the apical proton pump, which thus excretes acid into the urine. kAE1, the kidney isoform of AE1, exchanges bicarbonate for chloride on the basolateral surfac ... [...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] |
