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Tom20
Mitochondrial import receptor subunit TOM20 homolog is a protein that in humans is encoded by the ''TOMM20'' gene. TOM20 is one of the receptor systems of the TOM complex (translocase of the outer membrane) in the outer mitochondrial membrane (OMM). Function In mitochondrial protein import, TOM20 is closely associated with the pore-forming TOM40 complex and acts by recognizing and binding the N-terminal MTSs (matrix-targeting sequences), which form an amphipathic alpha helix and aid passage of the target proteins into the mitochondrial matrix. See also * Mitochondria Outer Membrane Translocase * TOMM22 * TOMM40 * TOMM70A Mitochondrial import receptor subunit TOM70 is a protein that in humans is encoded by the ''TOMM70A'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meani ... References Further reading * * * * * * * * * * * * * * * {{gene-1-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Translocase Of The Outer Membrane
The translocase of the outer membrane (TOM) is a complex of proteins found in the outer mitochondrial membrane of the mitochondria. It allows movement of proteins through this barrier and into the intermembrane space of the mitochondrion. Most of the proteins needed for mitochondrial function are encoded by the nucleus of the cell. The outer membrane of the mitochondrion is impermeable to large molecules greater than 5000 Daltons. The TOM works in conjunction with the translocase of the inner membrane (TIM) to translocate proteins into the mitochondrion. Many of the proteins in the TOM complex, such as TOMM22, were first identified in ''Neurospora crassa'' and ''Saccharomyces cerevisiae''. Many of the genes encoding these proteins are designated as TOMM (translocase of the outer mitochondrial membrane) complex genes. The complete mitochondrial protein translocase complex includes at least 19 proteins: several chaperones, four proteins of the outer membrane translocase (Tom) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TOMM22
Mitochondrial import receptor subunit TOM22 homolog is a protein that in humans is encoded by the ''TOMM22'' gene. The protein encoded by this gene is an integral membrane protein of the mitochondrial outer membrane. The encoded protein interacts with TOMM20 and TOMM40, and forms a complex with several other proteins to import cytosolic preproteins into the mitochondrion. See also * Mitochondria Outer Membrane Translocase * TOMM20 * TOMM40 * TOMM70A Mitochondrial import receptor subunit TOM70 is a protein that in humans is encoded by the ''TOMM70A'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meani ... References Further reading * * * * * * * * * * * * * * {{gene-22-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid ... [...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] |
Mitochondrial
A mitochondrion (; ) is an organelle found in the cells of most Eukaryotes, such as animals, plants and fungi. Mitochondria have a double membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is used throughout the cell as a source of chemical energy. They were discovered by Albert von Kölliker in 1857 in the voluntary muscles of insects. The term ''mitochondrion'' was coined by Carl Benda in 1898. The mitochondrion is popularly nicknamed the "powerhouse of the cell", a phrase coined by Philip Siekevitz in a 1957 article of the same name. Some cells in some multicellular organisms lack mitochondria (for example, mature mammalian red blood cells). A large number of unicellular organisms, such as microsporidia, parabasalids and diplomonads, have reduced or transformed their mitochondria into other structures. One eukaryote, ''Monocercomonoides'', is known to have completely lost its mitochondria, and one multicellular organism, ''Henneg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TOMM40
Translocase of outer mitochondrial membrane 40 homolog (yeast), also known as TOMM40, is a protein which in humans is encoded by the ''TOMM40'' gene. Function ''TOMM40'' codes for a protein that is embedded into outer membranes of mitochondria and is required for the movement of proteins into mitochondria. More precisely, TOMM40 is the channel-forming subunit of a translocase of the mitochondrial outer membrane ( TOM) that is essential for protein transport into mitochondria. Clinical significance In humans, certain alleles of this gene have been statistically associated with an increased risk of developing late-onset Alzheimer's disease.; One study has found that TOMM40 risk alleles appears twice as often in people with Alzheimer's disease than those without it. Because ''TOMM40'' is located on chromosome 19, and is closely adjacent to '' APOE'', another gene known to be associated with Alzheimer's, another study has suggested that the statistically significant correl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-terminus
The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the amine group is bonded to the carboxylic group of another amino acid, making it a chain. That leaves a free carboxylic group at one end of the peptide, called the C-terminus, and a free amine group on the other end called the N-terminus. By convention, peptide sequences are written N-terminus to C-terminus, left to right (in LTR writing systems). This correlates the translation direction to the text direction, because when a protein is translated from messenger RNA, it is created from the N-terminus to the C-terminus, as amino acids are added to the carboxyl end of the protein. Chemistry Each amino acid has an amine group and a carboxylic group. Amino acids link to one another by peptide bonds which form through a dehydration reaction that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphiphile
An amphiphile (from the Greek αμφις amphis, both, and φιλíα philia, love, friendship), or amphipath, is a chemical compound possessing both hydrophilic (''water-loving'', polar) and lipophilic (''fat-loving'') properties. Such a compound is called amphiphilic or amphipathic. Common amphiphilic substances are soaps, detergents, and lipoproteins. The phospholipid amphiphiles are the major structural component of cell membranes. Amphiphiles are the basis for a number of areas of research in chemistry and biochemistry, notably that of lipid polymorphism. Organic compounds containing hydrophilic groups at both ends of the molecule are called bolaamphiphilic. The micelles they form in the aggregate are prolate. Structure The lipophilic group is typically a large hydrocarbon moiety, such as a long chain of the form CH3(CH2)n, with n > 4. The hydrophilic group falls into one of the following categories: # charged groups #* anionic. Examples, with the lipophilic part ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Helix
The alpha helix (α-helix) is a common motif in the secondary structure of proteins and is a right hand- helix conformation in which every backbone N−H group hydrogen bonds to the backbone C=O group of the amino acid located four residues earlier along the protein sequence. The alpha helix is also called a classic Pauling–Corey–Branson α-helix. The name 3.613-helix is also used for this type of helix, denoting the average number of residues per helical turn, with 13 atoms being involved in the ring formed by the hydrogen bond. Among types of local structure in proteins, the α-helix is the most extreme and the most predictable from sequence, as well as the most prevalent. Discovery In the early 1930s, William Astbury showed that there were drastic changes in the X-ray fiber diffraction of moist wool or hair fibers upon significant stretching. The data suggested that the unstretched fibers had a coiled molecular structure with a characteristic repeat of ≈. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondrial Matrix
In the mitochondrion, the matrix is the space within the inner membrane. The word "matrix" stems from the fact that this space is viscous, compared to the relatively aqueous cytoplasm. The mitochondrial matrix contains the mitochondrial DNA, ribosomes, soluble enzymes, small organic molecules, nucleotide cofactors, and inorganic ions. /sup> The enzymes in the matrix facilitate reactions responsible for the production of ATP, such as the citric acid cycle, oxidative phosphorylation, oxidation of pyruvate, and the beta oxidation of fatty acids. The composition of the matrix based on its structures and contents produce an environment that allows the anabolic and catabolic pathways to proceed favorably for. The electron transport chain and enzymes in the matrix play a large role in the citric acid cycle and oxidative phosphorylation. The citric acid cycle produces NADH and FADH2 through oxidation that will be reduced in oxidative phosphorylation to produce ATP. The cytosolic, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
