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Acvrl1
Serine/threonine-protein kinase receptor R3 is an enzyme that in humans is encoded by the ''ACVRL1'' gene. ACVRL1 is a receptor in the TGF beta signaling pathway. It is also known as activin receptor-like kinase 1, or ALK1. Function This gene encodes a type I cell-surface receptor for the TGF-beta superfamily of ligands. It shares with other type I receptors a high degree of similarity in serine-threonine kinase subdomains, a glycine- and serine-rich region (called the GS domain) preceding the kinase domain, and a short C-terminal tail. The encoded protein, sometimes termed ALK1, shares similar domain structures with other closely related ALK or activin receptor-like kinase proteins that form a subfamily of receptor serine/threonine kinases. Mutations in this gene are associated with hereditary hemorrhagic telangiectasia (HHT) type 2, also known as Rendu-Osler-Weber syndrome 2. Pathology Germline mutations of ACVRL1 are associated with: * hereditary hemorrhagic telangiectasi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecules known as product (chemistry), products. Almost all metabolism, metabolic processes in the cell (biology), cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme, pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts include Ribozyme, catalytic RNA molecules, also called ribozymes. They are sometimes descr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. 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 non-coding genes. During gene expression (the synthesis of Gene product, RNA or protein from a gene), DNA is first transcription (biology), copied into RNA. RNA can be non-coding RNA, directly functional or be the intermediate protein biosynthesis, template for the synthesis of a protein. The transmission of genes to an organism's offspring, is the basis of the inheritance of phenotypic traits from one generation to the next. These genes make up different DNA sequences, together called a genotype, that is specific to every given individual, within the gene pool of the population (biology), population of a given species. The genotype, along with environmental and developmental factors, ultimately determines the phenotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TGF Beta Signaling Pathway
The transforming growth factor beta (TGFβ) signaling pathway is involved in many cellular processes in both the adult organism and the developing embryo including cell growth, cell differentiation, cell migration, apoptosis, cellular homeostasis and other cellular functions. The pathway is also involved in multiple physiological processes such as regulation of the immune system, the vascular system and embryonic development. The TGFβ signaling pathways are conserved. In spite of the wide range of cellular processes that the TGFβ signaling pathway regulates, the process is relatively simple. TGFβ superfamily ligands bind to a type II receptor, which recruits and phosphorylates a type I receptor. The type I receptor then phosphorylates receptor-regulated SMADs ( R-SMADs) which can now bind the coSMAD SMAD4. R-SMAD/coSMAD complexes accumulate in the nucleus where they act as transcription factors and participate in the regulation of target gene expression. Mechanism Ligand bind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germline Mutation
A germline mutation, or germinal mutation, is any detectable variation within germ cells (cells that, when fully developed, become sperm and Egg cell, ova). Mutations in these cells are the only mutations that can be passed on to offspring, when either a mutated sperm or oocyte come together to form a zygote. After this fertilization event occurs, germ cells divide rapidly to produce all of the cells in the body, causing this mutation to be present in every Somatic (biology), somatic and germline cell in the offspring; this is also known as a constitutional mutation. Germline mutation is distinct from somatic mutation. Germline mutations can be caused by a variety of endogenous (internal) and exogenous (external) factors, and can occur throughout zygote development. A mutation that arises only in germ cells can result in offspring with a genetic condition that is not present in either parent; this is because the mutation is not present in the rest of the parents' body, only the ger ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hereditary Hemorrhagic Telangiectasia
Hereditary hemorrhagic telangiectasia (HHT), also known as Osler–Weber–Rendu disease and Osler–Weber–Rendu syndrome, is a rare autosomal dominant genetic disorder that leads to abnormal blood vessel formation in the Human skin, skin, mucous membranes, and often in organs such as the lungs, liver, and brain. It may lead to epistaxis, nosebleeds, Gastrointestinal bleeding, acute and chronic digestive tract bleeding, and various problems due to the involvement of other organs. Treatment focuses on reducing bleeding from telangiectasias, and sometimes surgery or other targeted interventions to remove arteriovenous malformations in organs. Chronic bleeding often requires iron supplements, iron infusions and sometimes blood transfusions. HHT is transmitted in an Dominance (genetics), autosomal dominant fashion, and occurs in one in 5,000–8,000 people in North America. The disease carries the names of Sir William Osler, Henri Jules Louis Marie Rendu, and Frederick Parkes Weber ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arteriovenous Malformation
An arteriovenous malformation (AVM) is an abnormal connection between arteries and veins, bypassing the capillary system. Usually congenital, this vascular anomaly is widely known because of its occurrence in the central nervous system (usually as a cerebral AVM), but can appear anywhere in the body. The symptoms of AVMs can range from none at all to intense pain or bleeding, and they can lead to other serious medical problems. Signs and symptoms Symptoms of AVMs vary according to their location. Most neurological AVMs produce few to no symptoms. Often the malformation is discovered as part of an autopsy or during treatment of an unrelated disorder (an " incidental finding"); in rare cases, its expansion or a micro-bleed from an AVM in the brain can cause epilepsy, neurological deficit, or pain. The most general symptoms of a cerebral AVM include headaches and epileptic seizures, with more specific symptoms that normally depend on its location and the individual, in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Somatic Mosaicism
Mosaicism or genetic mosaicism is a condition in which a multicellular organism possesses more than one genetic line as the result of genetic mutation. This means that various genetic lines resulted from a single fertilized egg. Mosaicism is one of several possible causes of chimerism, wherein a single organism is composed of cells with more than one distinct genotype. Genetic mosaicism can result from many different mechanisms including chromosome nondisjunction, anaphase lag, and endoreplication. Anaphase lagging is the most common way by which mosaicism arises in the preimplantation embryo. Mosaicism can also result from a mutation in one cell during development, in which case the mutation will be passed on only to its daughter cells (and will be present only in certain adult cells). Somatic mosaicism is not generally inheritable as it does not generally affect germ cells. History In 1929, Alfred Sturtevant studied mosaicism in ''Drosophila'', a genus of fruit fly. H. J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulmonary Arterial Hypertension
Pulmonary arterial hypertension (PAH) is a syndrome in which the blood pressure in the pulmonary arteries and pulmonary arterioles (the blood vessels located proximal to the capillary bed, the site of oxygen exchange in the lungs) is elevated. This pre-capillary pulmonary artery pressure being elevated is essential, and by definition a mean pulmonary artery pressure greater than 20 mmHg as measured by a right heart catheterization is required for the diagnosis. This pre-capillary pulmonary hypertension is confirmed with measuring pulmonary vascular resistance being greater than 3 Woods Units. A pulmonary artery wedge pressure being less than 15 mmHg (also measured by right heart catheterization) excludes post-capillary bed (in the veins distal to the capillary bed) pulmonary hypertension. Pulmonary arterial hypertension is a subgroup of pulmonary hypertension and is categorized as World Health Organization as group 1. PAH is further subdivided into various categories based on t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low-density Lipoprotein
Low-density lipoprotein (LDL) is one of the five major groups of lipoprotein that transport all fat molecules around the body in extracellular water. These groups, from least dense to most dense, are chylomicrons (aka ULDL by the overall density naming convention), very low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), low-density lipoprotein (LDL) and high-density lipoprotein (HDL). LDL delivers fat molecules to Cell (biology), cells. LDL has been associated with the progression of atherosclerosis. Overview Lipoproteins transfer lipids (fats) around the body in the extracellular fluid, making fats available to body cells for receptor-mediated endocytosis. Lipoproteins are complex particles composed of multiple proteins, typically 80–100 proteins per particle (organized by a single apolipoprotein B for LDL and the larger particles). A single LDL particle is about 22–27.5 nanometers in diameter, typically transporting 3,000 to 6,000 fat molecules per part ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atherosclerosis
Atherosclerosis is a pattern of the disease arteriosclerosis, characterized by development of abnormalities called lesions in walls of arteries. This is a chronic inflammatory disease involving many different cell types and is driven by elevated blood levels of cholesterol. These lesions may lead to narrowing of the arterial walls due to buildup of atheromatous plaques. At the onset, there are usually no symptoms, but if they develop, symptoms generally begin around middle age. In severe cases, it can result in coronary artery disease, stroke, peripheral artery disease, or kidney disorders, depending on which body part(s) the affected arteries are located in the body. The exact cause of atherosclerosis is unknown and is proposed to be multifactorial. Risk factors include dyslipidemia, abnormal cholesterol levels, elevated levels of inflammatory biomarkers, high blood pressure, diabetes, smoking (both active and passive smoking), obesity, genetic factors, family history, lifes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anaplastic Lymphoma Kinase
Anaplastic lymphoma kinase (ALK) also known as ALK tyrosine kinase receptor or CD246 (cluster of differentiation 246) is an enzyme that in humans is encoded by the ''ALK'' gene. Identification Anaplastic lymphoma kinase (ALK) was originally discovered in 1994 in anaplastic large-cell lymphoma (ALCL) cells. ALCL is caused by a (2;5)(p23:q35) chromosomal translocation that generates the fusion protein NPM-ALK, in which the kinase domain of ALK is fused to the amino-terminal part of the nucleophosmin (NPM) protein. Dimerization of NPM constitutively activates the ALK kinase domain. The full-length protein ALK was identified in 1997 by two groups. The deduced amino acid sequences revealed that ALK was a novel receptor tyrosine kinase (RTK), having an extracellular ligand-binding domain, a transmembrane domain, and an intracellular tyrosine kinase domain. While the tyrosine kinase domain of human ALK shares a high degree of similarity with that of the insulin receptor, its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
