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Intercellular Adhesion Molecule
In molecular biology, intercellular adhesion molecules (ICAMs) and vascular cell adhesion molecule-1 (VCAM-1) are part of the immunoglobulin superfamily. They are important in inflammation, immune responses and in intracellular signalling events. The ICAM family consists of five members, designated ICAM-1 to ICAM-5. They are known to bind to leucocyte integrins CD11/CD18 such as LFA-1 and Macrophage-1 antigen, during inflammation and in immune responses. In addition, ICAMs may exist in soluble forms in human plasma, due to activation and proteolysis mechanisms at cell surfaces. Mammalian intercellular adhesion molecules include: * ICAM-1 * ICAM2 * ICAM3 * ICAM4 * ICAM5 Intercellular adhesion molecule 5 is a protein that in humans is encoded by the ''ICAM5'' gene. The protein encoded by this gene is a member of the intercellular adhesion molecule (ICAM) family. All ICAM proteins are type I transmembrane glycopr ... References Cell biology Protein families {{B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Biology
Molecular biology is the branch of biology that seeks to understand the molecular basis of biological activity in and between cells, including biomolecular synthesis, modification, mechanisms, and interactions. The study of chemical and physical structure of biological macromolecules is known as molecular biology. Molecular biology was first described as an approach focused on the underpinnings of biological phenomena - uncovering the structures of biological molecules as well as their interactions, and how these interactions explain observations of classical biology. In 1945 the term molecular biology was used by physicist William Astbury. In 1953 Francis Crick, James Watson, Rosalind Franklin, and colleagues, working at Medical Research Council unit, Cavendish laboratory, Cambridge (now the MRC Laboratory of Molecular Biology), made a double helix model of DNA which changed the entire research scenario. They proposed the DNA structure based on previous research done by R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrophage-1 Antigen
Macrophage-1 antigen (or integrin αMβ2 or macrophage integrin or Mac-1) is a complement receptor ("CR3") consisting of CD11b (integrin αM) and CD18 (integrin β2). The integrin α chain is noncovalently bound to the integrin β chain. It binds to iC3b and can be involved in cellular adhesion, binding to the intercellular adhesion molecule-1 (ICAM-1). CR3 causes phagocytosis and destruction of cells opsonized with iC3b. CR3 and CR4 are thought to exhibit overlapping functions; however, the distinct binding sites to iC3b suggests differences in their functions. Additionally, CR3 has been shown to have therapeutic promise. Function Macrophage-1 antigen (hereafter complement receptor 3 or CR3) (CD11b/CD18) is a human cell surface receptor found on B and T lymphocytes, polymorphonuclear leukocytes (mostly neutrophils), NK cells, and mononuclear phagocytes like macrophages. CR3 is a pattern recognition receptor, capable of recognizing and binding to many molecules found on the surf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ICAM5
Intercellular adhesion molecule 5 is a protein that in humans is encoded by the ''ICAM5'' gene. The protein encoded by this gene is a member of the intercellular adhesion molecule (ICAM) family. All ICAM proteins are type I transmembrane glycoproteins, contain 2-9 immunoglobulin-like C2-type domains, and bind to the leukocyte adhesion LFA-1 protein. This protein is expressed on the surface of telencephalic neurons and displays two types of adhesion activity, homophilic binding between neurons and heterophilic binding between neurons and leukocytes. It may be a critical component in neuron-microglial cell interactions in the course of normal development or as part of neurodegenerative diseases. Interactions ICAM5 has been shown to interact with PSEN1 Presenilin-1 (PS-1) is a presenilin protein that in humans is encoded by the ''PSEN1'' gene. Presenilin-1 is one of the four core proteins in the gamma secretase complex, which is considered to play an important role in generation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ICAM4
The LW blood system was first described by Landsteiner and Wiener in 1940. It was often confused with the Rh system, not becoming a separate antigen system until 1982. The LW and RhD antigens are genetically independent though they are phenotypically related and the LW antigen is expressed more strongly on RhD positive cells than on RhD negative cells. In most populations, the antithetical LW antigens, LWa and LWb are present as very high and very low frequency, respectively. Genomics The LW locus is located on the short arm of chromosome 19 (19p13.3). Molecular biology LW antigens reside on a 40- to 42-kiloDalton red cell membrane glycoprotein named CD242. The LW glycoprotein has recently been renamed ICAM-4 due to its similarity to intercellular adhesion molecule, although exactly which integrins bind to ICAM-4 is subject to controversy. The function of ICAM-4 is not fully understood but appears to be restricted to erythroid cells. During in vitro erythropoesis, LW appear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ICAM3
Intercellular adhesion molecule 3 (ICAM3) also known as CD50 (Cluster of Differentiation 50), is a protein that in humans is encoded by the ''ICAM3'' gene. The protein is constitutively expressed on the surface of leukocytes, which are also called white blood cells and are part of the immune system. ICAM3 mediates adhesion between cells by binding to specific integrin receptors. It plays an important role in the immune cell response through its facilitation of interactions between T cells and dendritic cells, which allows for T cell activation. ICAM3 also mediates the clearance of cells undergoing apoptosis by attracting and binding macrophages, a type of cell that breaks down infected or dying cells through a process known as phagocytosis, to apoptotic cells. Protein Structure ICAM3 is a 110-160 kDa protein that belongs to the intercellular adhesion molecule (ICAM) family. Like the other proteins in this family, ICAM3 is a type I transmembrane glycoprotein and consists in part o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ICAM2
Intercellular adhesion molecule 2 (ICAM2), also known as CD102 (Cluster of Differentiation 102), is a human gene, and the protein resulting from it. Protein structure The protein encoded by this gene is a member of the intercellular adhesion molecule (ICAM) family. All ICAM proteins are type I transmembrane glycoproteins, contain 2–9 immunoglobulin-like C2-type domains, and bind to the leukocyte adhesion LFA-1 protein. Protein functions ICAM-2 molecules regulate spermatid adhesion on Sertoli cell on the apical side of the blood-testis barrier (towards the lumen), thus playing a major role in spermatogenesis. This protein may also play a role in lymphocyte recirculation by blocking LFA-1-dependent cell adhesion. It mediates adhesive interactions important for antigen-specific immune response, NK-cell mediated clearance, lymphocyte recirculation, and other cellular interactions important for immune response and surveillance. Interactions ICAM2 has been shown to interact w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ICAM-1
ICAM-1 ( Intercellular Adhesion Molecule 1) also known as CD54 (Cluster of Differentiation 54) is a protein that in humans is encoded by the ''ICAM1'' gene. This gene encodes a cell surface glycoprotein which is typically expressed on endothelial cells and cells of the immune system. It binds to integrins of type CD11a / CD18, or CD11b / CD18 and is also exploited by rhinovirus as a receptor for entry into respiratory epithelium. Structure ICAM-1 is a member of the immunoglobulin superfamily, the superfamily of proteins including antibodies and T-cell receptors. ICAM-1 is a transmembrane protein possessing an amino-terminus extracellular domain, a single transmembrane domain, and a carboxy-terminus cytoplasmic domain. The structure of ICAM-1 is characterized by heavy glycosylation, and the protein’s extracellular domain is composed of multiple loops created by disulfide bridges within the protein. The dominant secondary structure of the protein is the beta sheet, leadi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell (biology)
The cell is the basic structural and functional unit of life forms. Every cell consists of a cytoplasm enclosed within a membrane, and contains many biomolecules such as proteins, DNA and RNA, as well as many small molecules of nutrients and metabolites.Cell Movements and the Shaping of the Vertebrate Body in Chapter 21 of Molecular Biology of the Cell '' fourth edition, edited by Bruce Alberts (2002) published by Garland Science. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos. It is also common to describe small molecules such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proteolysis
Proteolysis is the breakdown of proteins into smaller polypeptides or amino acids. Uncatalysed, the hydrolysis of peptide bonds is extremely slow, taking hundreds of years. Proteolysis is typically catalysed by cellular enzymes called proteases, but may also occur by intra-molecular digestion. Proteolysis in organisms serves many purposes; for example, digestive enzymes break down proteins in food to provide amino acids for the organism, while proteolytic processing of a polypeptide chain after its synthesis may be necessary for the production of an active protein. It is also important in the regulation of some physiological and cellular processes including apoptosis, as well as preventing the accumulation of unwanted or misfolded proteins in cells. Consequently, abnormality in the regulation of proteolysis can cause disease. Proteolysis can also be used as an analytical tool for studying proteins in the laboratory, and it may also be used in industry, for example in food pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Plasma
Blood plasma is a light amber-colored liquid component of blood in which blood cells are absent, but contains proteins and other constituents of whole blood in suspension. It makes up about 55% of the body's total blood volume. It is the intravascular part of extracellular fluid (all body fluid outside cells). It is mostly water (up to 95% by volume), and contains important dissolved proteins (6–8%; e.g., serum albumins, globulins, and fibrinogen), glucose, clotting factors, electrolytes (, , , , , etc.), hormones, carbon dioxide (plasma being the main medium for excretory product transportation), and oxygen. It plays a vital role in an intravascular osmotic effect that keeps electrolyte concentration balanced and protects the body from infection and other blood-related disorders. Blood plasma is separated from the blood by spinning a vessel of fresh blood containing an anticoagulant in a centrifuge until the blood cells fall to the bottom of the tube. The blood plasm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homo Sapiens
Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, and language. Humans are highly social and tend to live in complex social structures composed of many cooperating and competing groups, from families and kinship networks to political states. Social interactions between humans have established a wide variety of values, social norms, and rituals, which bolster human society. Its intelligence and its desire to understand and influence the environment and to explain and manipulate phenomena have motivated humanity's development of science, philosophy, mythology, religion, and other fields of study. Although some scientists equate the term ''humans'' with all members of the genus ''Homo'', in common usage, it generally refers to ''Homo sapiens'', the only extant member. Anatomically mod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LFA-1
Lymphocyte function-associated antigen 1 (LFA-1) is an integrin found on lymphocytes and other leukocytes. LFA-1 plays a key role in emigration, which is the process by which leukocytes leave the bloodstream to enter the tissues. LFA-1 also mediates firm arrest of leukocytes. Additionally, LFA-1 is involved in the process of cytotoxic T cell mediated killing as well as antibody mediated killing by granulocytes and monocytes. As of 2007, LFA-1 has 6 known ligands: ICAM-1, ICAM-2, ICAM-3, ICAM-4, ICAM-5, and JAM-A. LFA-1/ICAM-1 interactions have recently been shown to stimulate signaling pathways that influence T cell differentiation. LFA-1 belongs to the integrin superfamily of adhesion molecules. Structure LFA-1 is a heterodimeric glycoprotein with non-covalently linked subunits. LFA-1 has two subunits designated as the alpha subunit and beta subunit. The alpha subunit was named aL in 1983. The alpha subunit is designated CD11a; and the beta subunit, unique to leukocytes, is be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
