|
NDUFS1
NADH-ubiquinone oxidoreductase 75 kDa subunit, mitochondrial (NDUFS1) is an enzyme that in humans is encoded by the ''NDUFS1'' gene. The encoded protein, NDUFS1, is the largest subunit of complex I, located on the inner mitochondrial membrane, and is important for mitochondrial oxidative phosphorylation. Mutations in this gene are associated with complex I deficiency. Structure ''NDUFS1'' is located on the q arm of chromosome 2 in position 33.3 and has 20 exons. The ''NDUFS1'' gene produces a 79.5 kDa protein composed of 727 amino acids. NDUFS1, the protein encoded by this gene, is a member of the complex I 75 kDa subunit family. It contains a transit peptide, 10 turns, 19 beta strands, 27 alpha helixes, and cofactor binding sites for 2Fe-2S_cluster">2Fe-2S.html" ;"title="2Fe-2S_cluster.html" ;"title="nowiki/>2Fe-2S cluster">2Fe-2S">2Fe-2S_cluster.html" ;"title="nowiki/>2Fe-2S cluster">2Fe-2Sand [4Fe-4S] clusters. The cluster domains consist of a 79 amino acid 2Fe-2S ferre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Respiratory Complex I
Respiratory complex I, (also known as NADH:ubiquinone oxidoreductase, Type I NADH dehydrogenase and mitochondrial complex I) is the first large protein complex of the respiratory chains of many organisms from bacteria to humans. It catalyzes the transfer of electrons from NADH to coenzyme Q10 (CoQ10) and translocates protons across the inner mitochondrial membrane in eukaryotes or the plasma membrane of bacteria. This enzyme is essential for the normal functioning of cells, and mutations in its subunits lead to a wide range of inherited neuromuscular and metabolic disorders. Defects in this enzyme are responsible for the development of several pathological processes such as ischemia/reperfusion damage (stroke and cardiac infarction), Parkinson's disease and others. Function Complex I is the first enzyme of the mitochondrial electron transport chain. There are three energy-transducing enzymes in the electron transport chain - NADH:ubiquinone oxidoreductase (complex I), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the 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 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 are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Isoform
A protein isoform, or "protein variant", is a member of a set of highly similar proteins that originate from a single gene or gene family and are the result of genetic differences. While many perform the same or similar biological roles, some isoforms have unique functions. A set of protein isoforms may be formed from alternative splicings, variable promoter usage, or other post-transcriptional modifications of a single gene; post-translational modifications are generally not considered. (For that, see Proteoforms.) Through RNA splicing mechanisms, mRNA has the ability to select different protein-coding segments ( exons) of a gene, or even different parts of exons from RNA to form different mRNA sequences. Each unique sequence produces a specific form of a protein. The discovery of isoforms could explain the discrepancy between the small number of protein coding regions genes revealed by the human genome project and the large diversity of proteins seen in an organism: different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encephalopathy
Encephalopathy (; from grc, ἐνκέφαλος "brain" + πάθος "suffering") means any disorder or disease of the brain, especially chronic degenerative conditions. In modern usage, encephalopathy does not refer to a single disease, but rather to a syndrome of overall brain dysfunction; this syndrome has many possible organic and inorganic causes. Signs and symptoms The hallmark of encephalopathy is an altered mental state or delirium. Characteristic of the altered mental state is impairment of the cognition, attention, orientation, sleep–wake cycle and consciousness. An altered state of consciousness may range from failure of selective attention to drowsiness. Hypervigilance may be present; with or without: cognitive deficits, headache, epileptic seizures, myoclonus (involuntary twitching of a muscle or group of muscles) or asterixis ("flapping tremor" of the hand when wrist is extended). Depending on the type and severity of encephalopathy, common neurological sym ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leukodystrophy
Leukodystrophies are a group of usually inherited disorders characterized by degeneration of the white matter in the brain. The word ''leukodystrophy'' comes from the Greek roots ''leuko'', "white", ''dys'', "abnormal" and ''troph'', "growth". The leukodystrophies are caused by imperfect growth or development of the myelin sheath, the fatty insulating covering around nerve fibers. Leukodystrophies may be classified as hypomyelinating or demyelinating diseases, depending on whether the damage is present before birth or occurs after. Other demyelinating diseases are usually not congenital and have a toxic or autoimmune cause. When damage occurs to white matter, immune responses can lead to inflammation in the central nervous system (CNS), along with loss of myelin. The degeneration of white matter can be seen in an MRI scan and used to diagnose leukodystrophy. Leukodystrophy is characterized by specific symptoms including decreased motor function, muscle rigidity, and eventual dege ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrocephaly
Macrocephaly is a condition in which circumference of the human head is abnormally large. It may be pathological or harmless, and can be a familial genetic characteristic. People diagnosed with macrocephaly will receive further medical tests to determine whether the syndrome is accompanied by particular disorders. Those with benign or familial macrocephaly are considered to have megalencephaly. Causes Many people with abnormally large heads or large skulls are healthy, but macrocephaly may be pathological. Pathologic macrocephaly may be due to megalencephaly (enlarged brain), hydrocephalus (abnormally increased cerebrospinal fluid), cranial hyperostosis (bone overgrowth), and other conditions. Pathologic macrocephaly is called "syndromic", when it is associated with any other noteworthy condition, and "nonsyndromic" otherwise. Pathologic macrocephaly may be caused by congenital anatomic abnormalities, genetic conditions, or by environmental events. Many genetic conditions are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genotype–phenotype Distinction
The genotype–phenotype distinction is drawn in genetics. " Genotype" is an organism's full hereditary information. "Phenotype" is an organism's actual observed properties, such as morphology, development, or behavior. This distinction is fundamental in the study of inheritance of traits and their evolution. Overview The terms "genotype" and "phenotype" were created by Wilhelm Johannsen in 1911, although the meaning of the terms and the significance of the distinction have evolved since they were introduced. It is the organism's physical properties that directly determine its chances of survival and reproductive output, but the inheritance of physical properties is dependent on the inheritance of genes. Therefore, understanding the theory of evolution via natural selection requires understanding the genotype–phenotype distinction. The genes contribute to a trait, and the phenotype is the observable expression of the genes (and therefore the genotype that affects the trait). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Heterogeneity
Genetic heterogeneity occurs through the production of single or similar phenotypes through different genetic mechanisms. There are two types of genetic heterogeneity: allelic heterogeneity, which occurs when a similar phenotype is produced by different alleles within the same gene; and ''locus'' heterogeneity, which occurs when a similar phenotype is produced by mutations at different ''loci''. Role in medical disorders Marked genetic heterogeneity is correlated to multiple levels of causation in many common human diseases including cystic fibrosis, Alzheimer's disease, autism spectrum disorders, inherited predisposition to breast cancer, and non-syndromic hearing loss. These levels of causation are complex and occur through: (1) rare, individual mutations that when combined contribute to the development of common diseases; (2) the accumulation of many different rare, individual mutations within the same gene that contribute to the development of the same common disease within diff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dominance (genetics)
In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The first variant is termed dominant and the second recessive. This state of having two different variants of the same gene on each chromosome is originally caused by a mutation in one of the genes, either new (''de novo'') or inherited. The terms autosomal dominant or autosomal recessive are used to describe gene variants on non-sex chromosomes ( autosomes) and their associated traits, while those on sex chromosomes (allosomes) are termed X-linked dominant, X-linked recessive or Y-linked; these have an inheritance and presentation pattern that depends on the sex of both the parent and the child (see Sex linkage). Since there is only one copy of the Y chromosome, Y-linked traits cannot be dominant or recessive. Additionally, there are other forms of dominance such as incomplete d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron-sulfur Protein
Iron–sulfur proteins (or iron–sulphur proteins in British spelling) are proteins characterized by the presence of iron–sulfur clusters containing sulfide-linked di-, tri-, and tetrairon centers in variable oxidation states. Iron–sulfur clusters are found in a variety of metalloproteins, such as the ferredoxins, as well as NADH dehydrogenase, hydrogenases, coenzyme Q – cytochrome c reductase, succinate – coenzyme Q reductase and nitrogenase. Iron–sulfur clusters are best known for their role in the oxidation-reduction reactions of electron transport in mitochondria and chloroplasts. Both Complex I and Complex II of oxidative phosphorylation have multiple Fe–S clusters. They have many other functions including catalysis as illustrated by aconitase, generation of radicals as illustrated by SAM-dependent enzymes, and as sulfur donors in the biosynthesis of lipoic acid and biotin. Additionally, some Fe–S proteins regulate gene expression. Fe–S proteins are vulnerabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ubiquinone
Coenzyme Q, also known as ubiquinone and marketed as CoQ10, is a coenzyme family that is ubiquitous in animals and most bacteria (hence the name ubiquinone). In humans, the most common form is coenzyme Q10 or ubiquinone-10. It is a 1,4-benzoquinone, where Q refers to the quinone chemical group and 10 refers to the number of isoprenyl chemical subunits in its tail. In natural ubiquinones, the number can be anywhere from 6 to 10. This family of fat-soluble substances, which resemble vitamins, is present in all respiring eukaryotic cells, primarily in the mitochondria. It is a component of the electron transport chain and participates in aerobic cellular respiration, which generates energy in the form of ATP. Ninety-five percent of the human body's energy is generated this way. Organs with the highest energy requirements—such as the heart, liver, and kidney—have the highest CoQ10 concentrations. There are three redox states of CoQ: fully oxidized (ubiquinone), semiquinone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Respiratory Chain
An electron transport chain (ETC) is a series of protein complexes and other molecules that transfer electrons from electron donors to electron acceptors via redox reactions (both reduction and oxidation occurring simultaneously) and couples this electron transfer with the transfer of protons (H+ ions) across a membrane. The electrons that transferred from NADH and FADH2 to the ETC involves 4 multi-subunit large enzymes complexes and 2 mobile electron carriers. Many of the enzymes in the electron transport chain are membrane-bound. The flow of electrons through the electron transport chain is an exergonic process. The energy from the redox reactions creates an electrochemical proton gradient that drives the synthesis of adenosine triphosphate (ATP). In aerobic respiration, the flow of electrons terminates with molecular oxygen as the final electron acceptor. In anaerobic respiration, other electron acceptors are used, such as sulfate. In an electron transport chain, the redox ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.png "Click for more on -> Respiratory Complex I")
