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GP1BB
Glycoprotein Ib (platelet), beta polypeptide (GP1BB) also known as CD42c (Cluster of Differentiation 42c), is a protein that in humans is encoded by the GP1BB gene. Function Platelet glycoprotein Ib (GPIb) is a heterodimeric transmembrane protein consisting of a disulfide-linked 140 kD alpha chain and 22 kD beta chain. It is part of the Glycoprotein Ib-IX-V Receptor Complex (GPIb-V-IX) system that constitutes the receptor for von Willebrand factor (VWF), and mediates platelet adhesion in the arterial circulation. GPIb alpha chain provides the VWF binding site, and GPIb beta contributes to surface expression of the receptor and participates in transmembrane signaling through phosphorylation of its intracellular domain. Mutations in the GPIb beta subunit have been associated with Bernard–Soulier syndrome, velocardiofacial syndrome and giant platelet disorder. The 206 amino acid precursor of GPIb beta is synthesized from a 1.0 kb mRNA expressed in plateletes and megakaryocytes. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bernard–Soulier Syndrome
Bernard–Soulier syndrome (BSS) is a rare autosomal recessive bleeding disorder that is caused by a deficiency of the ''glycoprotein Ib-IX-V complex'' (GPIb-IX-V), the receptor for von Willebrand factor. The incidence of BSS is estimated to be less than 1 case per million persons, based on cases reported from Europe, North America, and Japan. BSS is a giant platelet disorder, meaning that it is characterized by abnormally large platelets. Signs and symptoms Bernard–Soulier syndrome often presents as a bleeding disorder with symptoms of: Genetics In regards to mechanism, there are three genes: GP1BA, GP1BB and GP9 that are involved (due to mutations). These mutations do not allow the GPIb-IX-V complex to bind to the von Willebrand factor, which in turn is what would help platelets adhere to a site of injury which eventually helps stop bleeding. Diagnosis In terms of diagnosis Bernard–Soulier syndrome is characterized by prolonged bleeding time, thrombocytopenia, increa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycoprotein Ib-IX-V Receptor Complex
The GPIb-IX-V complex is a profuse membrane receptor complex originating in megakaryocytes and exclusively functional on the surface of platelets. It primarily functions to mediate the first critical step in platelet adhesion, by facilitating binding to von Willebrand factor (VWF) on damaged sub-endothelium under conditions of high fluid shear stress. Although the primary ligand for the GPIb-V-IX receptor is VWF, it can also bind to a number of other ligands in the circulation such as thrombin, P-selectin, factor XI, factor XII, high molecular weight kininogen as well as bacteria. GPIb-IX-V offers a critical role in thrombosis, metastasis, and the life cycle of platelets, and is implicated in a number of thrombotic pathological processes such as stroke or myocardial infarction. Molecular structure Overview GPIb-IX-V consists of four different subunits namely: GPIbα ( molecular weight (MW) 135 kDa), GPIbβ (MW 26 kDa), GPIX (MW 20 kDa) and GPV (MW 82kDa). The complex is assembl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
YWHAZ
14-3-3 protein zeta/delta (14-3-3ζ) is a protein that in humans is encoded by the ''YWHAZ'' gene on chromosome 8. The protein encoded by this gene is a member of the 14-3-3 protein family and a central hub protein for many signal transduction pathways. 14-3-3ζ is a major regulator of apoptotic pathways critical to cell survival and plays a key role in a number of cancers and neurodegenerative diseases. Structure 14-3-3 proteins generally form ~30 kDa-long homo- or heterodimers. Each of the monomers are composed of 9 antiparallel alpha helices. Four alpha-helices (αC, αE, αG, and αI) form an amphipathic groove that serves as the ligand binding site, which can recognize three types of consensus binding motifs: RXX(pS/pT)XP, RXXX(pS/pT)XP, and (pS/pT)X1-2-COOH (where pS/pT represents phosphorylated serine/threonine). In addition to these primary interactions, the target protein can also bind outside the groove via secondary interactions. In particular, the crystallized st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Velocardiofacial Syndrome
DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a syndrome caused by a microdeletion on the long arm of chromosome 22. While the symptoms can vary, they often include congenital heart problems, specific facial features, frequent infections, developmental delay, learning problems and cleft palate. Associated conditions include kidney problems, schizophrenia, hearing loss and autoimmune disorders such as rheumatoid arthritis or Graves' disease. DiGeorge syndrome is typically due to the deletion of 30 to 40 genes in the middle of chromosome 22 at a location known as ''22q11.2''. About 90% of cases occur due to a new mutation during early development, while 10% are inherited from a person's parents. It is autosomal dominant, meaning that only one affected chromosome is needed for the condition to occur. Diagnosis is suspected based on the symptoms and confirmed by genetic testing. Although there is no cure, treatment can improve symptoms. This often includes a mult ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giant Platelet Disorder
Giant platelet disorders, also known as macrothrombocytopenia, are rare disorders featuring abnormally large platelets, thrombocytopenia and a tendency to bleeding. Giant platelets cannot stick adequately to an injured blood vessel walls, resulting in abnormal bleeding when injured. Giant platelet disorder occurs for inherited diseases like Bernard–Soulier syndrome, gray platelet syndrome and May–Hegglin anomaly. Signs and symptoms Symptoms usually present from the period of birth to early childhood as: nose bleeds, bruising, and/or gum bleeding. Problems later in life may arise from anything that can cause internal bleeding such as: stomach ulcers, surgery, trauma, or menstruation. Abnormality of the abdomen, nosebleeds, heavy menstrual bleeding, purpura, too few platelets circulating in the blood, and prolonged bleeding time have also been listed as symptoms of various giant platelet disorders. Genetics Many of the further classifications of giant platelet disorder occu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein–protein Interaction
Protein–protein interactions (PPIs) are physical contacts of high specificity established between two or more protein molecules as a result of biochemical events steered by interactions that include electrostatic forces, hydrogen bonding and the hydrophobic effect. Many are physical contacts with molecular associations between chains that occur in a cell or in a living organism in a specific biomolecular context. Proteins rarely act alone as their functions tend to be regulated. Many molecular processes within a cell are carried out by molecular machines that are built from numerous protein components organized by their PPIs. These physiological interactions make up the so-called interactomics of the organism, while aberrant PPIs are the basis of multiple aggregation-related diseases, such as Creutzfeldt–Jakob and Alzheimer's diseases. PPIs have been studied with many methods and from different perspectives: biochemistry, quantum chemistry, molecular dynamics, signal trans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cluster Of Differentiation
The cluster of differentiation (also known as cluster of designation or classification determinant and often abbreviated as CD) is a protocol used for the identification and investigation of cell surface molecules providing targets for immunophenotyping of cells. In terms of physiology, CD molecules can act in numerous ways, often acting as receptors or ligands important to the cell. A signal cascade is usually initiated, altering the behavior of the cell (see cell signaling). Some CD proteins do not play a role in cell signaling, but have other functions, such as cell adhesion. CD for humans is numbered up to 371 (). Nomenclature The CD nomenclature was proposed and established in the 1st International Workshop and Conference on Human Leukocyte Differentiation Antigens (HLDA), which was held in Paris in 1982. This system was intended for the classification of the many monoclonal antibodies (mAbs) generated by different laboratories around the world against epitopes on the su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
