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PLD2
Phospholipase D2 is an enzyme that in humans is encoded by the ''PLD2'' gene. Function Phosphatidylcholine (PC)-specific phospholipases D (PLDs) catalyze the hydrolysis of PC to produce phosphatidic acid and choline. Activation of PC-specific PLDs occurs as a consequence of agonist stimulation of both tyrosine kinase and G protein-coupled receptors. PC-specific PLDs have been proposed to function in regulated secretion, cytoskeletal reorganization, transcriptional regulation, and cell cycle control. upplied by OMIMref name="entrez"> Mechanism of activation PLD2 is activated by substrate presentation. The enzyme is palmitoylated, which drives PLD2 to lipid rafts. PC substrate is polyunsaturated and resides in the membrane separately from lipid rafts near phosphatidylinositol 4,5-bisphosphate (PIP2). When PIP2 levels increase, PLD2 trafficks to PIP2 where it encounters its substrate PC. Scaffolding proteins that interact with PLD2 likely changes its preference of lipid rafts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phospholipase D
Phospholipase D (EC 3.1.4.4, lipophosphodiesterase II, lecithinase D, choline phosphatase, PLD; systematic name phosphatidylcholine phosphatidohydrolase) is an enzyme of the phospholipase superfamily that catalyses the following reaction : a phosphatidylcholine + H2O = choline + a phosphatidate Phospholipases occur widely, and can be found in a wide range of organisms, including bacteria, yeast, plants, animals, and viruses. Phospholipase D's principal substrate is phosphatidylcholine, which it hydrolyzes to produce the signal molecule phosphatidic acid (PA), and soluble choline in a cholesterol dependent process called substrate presentation. Plants contain numerous genes that encode various PLD isoenzymes, with molecular weights ranging from 90 to 125 kDa. Mammalian cells encode two isoforms of phospholipase D: PLD1 and PLD2. Phospholipase D is an important player in many physiological processes, including membrane trafficking, cytoskeletal reorganization, recept ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phospholipase D1
Phospholipase D1 (PLD1) is an enzyme that in humans is encoded by the ''PLD1'' gene, though analogues are found in plants, fungi, prokaryotes, and even viruses. History The possibility of PLD1 was first mentioned in 1947 by authors Hanahan and Chaikoff at Berkeley when describing a carrot enzyme that could " plitcholine from phospholipids." PLD was first derived in mammals in 1975 by Saito and Kanfer, who noted its activity in rats. PLD was first cloned from HeLa cell cDNA in 1995, while mammalian PLD1 was first cloned from a rat in 1997. Function Phosphatidylcholine (PC)-specific phospholipases D (PLDs) catalyze the hydrolysis of PC to produce phosphatidic acid (PA) and choline. A range of agonists acting through G protein-coupled receptors and receptor tyrosine kinases stimulate this hydrolysis. PC-specific PLD activity has been implicated in numerous cellular pathways, including membrane trafficking, signal transduction, platelet coagulation, mitosis, apoptosis, and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate Presentation
Substrate presentation is a biological process that activates a protein. The protein is sequestered away from its substrate and then activated by release and exposure of the protein to its substrate. A substrate is typically the substance on which an enzyme acts but can also be a protein surface to which a ligand binds. The substrate is the material acted upon. In the case of an interaction with an enzyme, the protein or organic substrate typically changes chemical form. Substrate presentation differs from allosteric regulation in that the enzyme need not change its conformation to begin catalysis. Substrate presentation is best described for nanoscopic distances (<100 nm). 
Examples Amyloid Precursor Protein |
Aldolase A
Aldolase A (ALDOA, or ALDA), also known as fructose-bisphosphate aldolase, is an enzyme that in humans is encoded by the ''ALDOA'' gene on chromosome 16. The protein encoded by this gene is a glycolytic enzyme that catalyzes the reversible conversion of fructose-1,6-bisphosphate to glyceraldehyde 3-phosphate (G3P) and dihydroxyacetone phosphate (DHAP). Three aldolase isozymes (A, B, and C), encoded by three different genes, are differentially expressed during development. Aldolase A is found in the developing embryo and is produced in even greater amounts in adult muscle. Aldolase A expression is repressed in adult liver, kidney and intestine and similar to aldolase C levels in brain and other nervous tissue. Aldolase A deficiency has been associated with myopathy and hemolytic anemia. Alternative splicing and alternative promoter usage results in multiple transcript variants. Related pseudogenes have been identified on chromosomes 3 and 10. rovided by RefSeq, Aug 2011ref name ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PRKCD
Protein kinase C delta type (or PKC-δ) is an enzyme that in humans is encoded by the ''PRKCD'' gene. Function Protein kinase C (PKC) is a family of serine- and threonine-specific protein kinases that can be activated by the second messenger diacylglycerol. PKC family members phosphorylate a wide variety of protein targets and are known to be involved in diverse cellular signaling pathways. PKC family members also serve as major receptors for phorbol esters, a class of tumor promoters. Each member of the PKC family has a specific expression profile and is believed to play distinct roles in cells. The protein encoded by this gene is one of the PKC family members. Studies both in human and mice demonstrate that this kinase is involved in B cell signaling and in the regulation of growth, apoptosis, and differentiation of a variety of cell types. Protein kinase C delta is also regulated by phosphorylation on various serine/threonine (e.g. T50, T141, S304, T451, T505, S506, T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PLCG1
Phospholipase C, gamma 1, also known as PLCG1,is a protein that in humans involved in cell growth, migration, apoptosis, and proliferation. It is encoded by the ''PLCG1'' gene and is part of the PLC superfamily. Function PLCγ1 is a cell growth factor from the PLC superfamily. PLCγ1 is used during the cell growth and in a cell migration and apoptosis, all of which are vital cell processes that, if disrupted by mutations, can cause cancerous cells to form within the body. Mutations in this protein show an increase in issues in cells regarding regulation of proliferation and their cell signaling. PLCγ1 roles are also involved in neuronal actin growth, calcium signaling, and brain development. It is highly regulated by multiple factors, such as PIK3, AMPK, and FAK. It is part of the PIP3 pathway and leads to and increase in calcium in the cells. In neuronal cells, PLCγ1 is highly involved in actin cytoskeleton organization and synaptic plasticity. The basic PLCγ1 pathway ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caveolin 1
Caveolin-1 is a protein that in humans is encoded by the ''CAV1'' gene. Function The scaffolding protein encoded by this gene is the main component of the caveolae plasma membranes found in most cell types. The protein links integrin subunits to the tyrosine kinase FYN, an initiating step in coupling integrins to the Ras-ERK pathway and promoting cell cycle progression. The gene is a tumor suppressor gene candidate and a negative regulator of the Ras-p42/44 MAP kinase cascade. CAV1 and CAV2 are located next to each other on chromosome 7 and express colocalizing proteins that form a stable hetero-oligomeric complex. By using alternative initiation codons in the same reading frame, two isoforms (alpha and beta) are encoded by a single transcript from this gene. Interactions Caveolin 1 has been shown to interact with heterotrimeric G proteins, Src tyrosine kinases ( Src, Lyn) and H-Ras, cholesterol, TGF beta receptor 1, endothelial NOS, androgen receptor, amyloid precursor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BIN1
Myc box-dependent-interacting protein 1, also known as Bridging Integrator-1 and Amphiphysin-2 is a protein that in humans is encoded by the ''BIN1'' gene. This gene encodes several isoforms of a nucleocytoplasmic adaptor protein, one of which was initially identified as a MYC-interacting protein with features of a tumor suppressor. Isoforms that are expressed in the central nervous system may be involved in synaptic vesicle endocytosis and may interact with dynanim, synaptojanin, endophilin, and clathrin. Isoforms that are expressed in muscle and ubiquitously expressed isoforms localize to the cytoplasm and nucleus and activate a caspase-independent apoptotic process. Studies in mouse suggest that this gene plays an important role in cardiac muscle development. Alternate splicing of the gene results in ten transcript variants encoding different isoforms. Aberrant splice variants expressed in tumor cell lines have also been described. Clinical significance In humans, mutation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphiphysin
Amphiphysin is a protein that in humans is encoded by the ''AMPH'' gene. Function This gene encodes a protein associated with the cytoplasmic surface of synaptic vesicles. A subset of patients with stiff person syndrome who were also affected by breast cancer are positive for autoantibodies against this protein. Alternate splicing of this gene results in two transcript variants encoding different isoforms. Additional splice variants have been described, but their full length sequences have not been determined. Amphiphysin is a brain-enriched protein with an N-terminal lipid interaction, dimerisation and membrane bending BAR domain, a middle clathrin and adaptor binding domain and a C-terminal SH3 domain. In the brain, its primary function is thought to be the recruitment of dynamin to sites of clathrin-mediated endocytosis. There are 2 mammalian amphiphysins with similar overall structure. A ubiquitous splice form of amphiphysin-2 ( BIN1) that does not contain clathrin or adap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ARF1
ADP-ribosylation factor 1 is a protein that in humans is encoded by the ''ARF1'' gene. Function ADP-ribosylation factor 1 (ARF1) is a member of the human ARF gene family. The family members encode small guanine nucleotide-binding proteins that stimulate the ADP-ribosyltransferase activity of cholera toxin and play a role in vesicular trafficking as activators of phospholipase D. The gene products, including 6 ARF proteins and 11 ARF-like proteins, constitute a family of the RAS superfamily. The ARF proteins are categorized as class I (ARF1, ARF2 and ARF3), class II (ARF4 and ARF5) and class III (ARF6), and members of each class share a common gene organization. The ARF1 protein is localized to the Golgi apparatus and has a central role in intra-Golgi transport. Multiple alternatively spliced transcript variants encoding the same protein have been found for this gene. The major mechanism of action of Brefeldin A is through inhibition of ARF1. Interactions ARF1 has been shown ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
