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ARHGAP11B
''ARHGAP11B'' is a human-specific gene that amplifies basal progenitors, controls neural progenitor proliferation, and contributes to neocortex folding. It is capable of causing neocortex folding in mice. This likely reflects a role for ''ARHGAP11B'' in development and evolutionary expansion of the human neocortex, a conclusion consistent with the finding that the gene duplication that created ''ARHGAP11B'' occurred on the human lineage after the divergence from the chimpanzee lineage but before the divergence from Neanderthals. Structure ''ARHGAP11B'' encodes 267 amino acids. A truncated copy of '' ARHGAP11A'', which is found throughout the animal kingdom and encodes a Rho GTPase-activating-protein (RhoGAP domain), ''ARHGAP11B'' comprises most of the GAP domain (until lysine-220), followed by a novel C-terminal sequence that lacks the 756 C-terminal amino acids of ''ARHGAP11A''. Activity In contrast to full-length ''ARHGAP11A'' and ''ARHGAP11A 1-250'', ''ARHGAP11B'', like '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Brain
The human brain is the central organ of the human nervous system, and with the spinal cord makes up the central nervous system. The brain consists of the cerebrum, the brainstem and the cerebellum. It controls most of the activities of the body, processing, integrating, and coordinating the information it receives from the sense organs, and making decisions as to the instructions sent to the rest of the body. The brain is contained in, and protected by, the skull bones of the head. The cerebrum, the largest part of the human brain, consists of two cerebral hemispheres. Each hemisphere has an inner core composed of white matter, and an outer surface – the cerebral cortex – composed of grey matter. The cortex has an outer layer, the neocortex, and an inner allocortex. The neocortex is made up of six neuronal layers, while the allocortex has three or four. Each hemisphere is conventionally divided into four lobes – the frontal, temporal, parietal, and occipital lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolution Of The Brain
There is much to be discovered about the evolution of the brain and the principles that govern it. While much has been discovered, not everything currently known is well understood. The evolution of the brain has appeared to exhibit diverging adaptations within taxonomic classes such as mammalia and more vastly diverse adaptations across other taxonomic classes. Brain to body size scales allometrically. This means as body size changes, so do other physiological, anatomical, and biochemical constructs connecting the brain to the body. Small bodied mammals have relatively large brains compared to their bodies whereas large mammals (such as whales) have smaller brain to body ratios. If brain weight is plotted against body weight for primates, the regression line of the sample points can indicate the brain power of a primate species. Lemurs for example fall below this line which means that for a primate of equivalent size, we would expect a larger brain size. Humans lie well above the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RhoGAP Domain
RhoGAP domain is an evolutionary conserved protein domain of GTPase activating proteins towards Rho/ Rac/ Cdc42-like small GTPases. Human proteins containing this domain ABR; ARHGAP1; ARHGAP10; ARHGAP11A; ARHGAP11B; ARHGAP12; ARHGAP15; ARHGAP17; ARHGAP18; ARHGAP19; ARHGAP20; ARHGAP21; ARHGAP22; ARHGAP23; ARHGAP24; ARHGAP25; ARHGAP26; ARHGAP27; ARHGAP28; ARHGAP29; ARHGAP30; ARHGAP4; ARHGAP5; ARHGAP6; ARHGAP8; ARHGAP9; BCR; BPGAP1; C1; C5orf5; CDGAP; CENTD1; CENTD2; CENTD3; CHN1; CHN2; DEPDC1; DEPDC1A; DEPDC1B; DLC1; FAM13A1; FKSG42; GMIP; GRLF1; HMHA1; INPP5B; KIAA1688; LOC553158; MYO9A; MYO9B; OCRL; OPHN1; PIK3R1; PIK3R2; PRR5; RACGAP1; RACGAP1P; RALBP1; RICH2; RICS; SH3BP1; SLIT1; SNX26; SRGAP1; SRGAP2; SRGAP3; STARD13; STARD8 StAR-related lipid transfer domain protein 8 (STA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glutaminolysis
Glutaminolysis (''glutamine'' + '' -lysis'') is a series of biochemical reactions by which the amino acid glutamine is lysed to glutamate, aspartate, CO2, pyruvate, lactate, alanine and citrate. The glutaminolytic pathway Glutaminolysis partially recruits reaction steps from the citric acid cycle and the malate-aspartate shuttle. Reaction steps from glutamine to α-ketoglutarate The conversion of the amino acid glutamine to α-ketoglutarate takes place in two reaction steps: 1. Hydrolysis of the amino group of glutamine yielding glutamate and ammonium. Catalyzing enzyme: glutaminase (EC 3.5.1.2) 2. Glutamate can be excreted or can be further metabolized to α-ketoglutarate. For the conversion of glutamate to α-ketoglutarate three different reactions are possible: Catalyzing enzymes: *glutamate dehydrogenase (GlDH), EC 1.4.1.2 *glutamate pyruvate transaminase (GPT), also called alanine transaminase (ALT), EC 2.6.1.2 *glutamate oxaloacetate transaminase (GOT), also ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Single-nucleotide Polymorphism
In genetics, a single-nucleotide polymorphism (SNP ; plural SNPs ) is a germline substitution of a single nucleotide at a specific position in the genome. Although certain definitions require the substitution to be present in a sufficiently large fraction of the population (e.g. 1% or more), many publications do not apply such a frequency threshold. For example, at a specific base position in the human genome, the G nucleotide may appear in most individuals, but in a minority of individuals, the position is occupied by an A. This means that there is a SNP at this specific position, and the two possible nucleotide variations – G or A – are said to be the alleles for this specific position. SNPs pinpoint differences in our susceptibility to a wide range of diseases, for example age-related macular degeneration (a common SNP in the CFH gene is associated with increased risk of the disease) or nonalcoholic fatty liver disease (a SNP in the PNPLA3 gene is associated with inc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mitosis, or meiosis or other types of damage to DNA (such as pyrimidine dimers caused by exposure to ultraviolet radiation), which then may undergo error-prone repair (especially microhomology-mediated end joining), cause an error during other forms of repair, or cause an error during replication (translesion synthesis). Mutations may also result from insertion or deletion of segments of DNA due to mobile genetic elements. Mutations may or may not produce detectable changes in the observable characteristics (phenotype) of an organism. Mutations play a part in both normal and abnormal biological processes including: evolution, cancer, and the development of the immune system, including junctional diversity. Mutation is the ultimate source o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxoglutarate Dehydrogenase Complex
The oxoglutarate dehydrogenase complex (OGDC) or α-ketoglutarate dehydrogenase complex is an enzyme complex, most commonly known for its role in the citric acid cycle. Units Much like pyruvate dehydrogenase complex (PDC), this enzyme forms a complex composed of three components: Three classes of these multienzyme complexes have been characterized: one specific for pyruvate, a second specific for 2-oxoglutarate, and a third specific for branched-chain α-keto acids. The oxoglutarate dehydrogenase complex has the same subunit structure and thus uses the same coenzymes as the pyruvate dehydrogenase complex and the branched-chain alpha-keto acid dehydrogenase complex (TTP, CoA, lipoate, FAD and NAD). Only the E3 subunit is shared in common between the three enzymes. Properties Metabolic pathways This enzyme participates in three different pathways: * Citric acid cycle (KEGG linkMAP00020 * Lysine degradation (KEGG linkMAP00310 * Tryptophan metabolism (KEGG linkMAP00380 K ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Citric Acid Cycle
The citric acid cycle (CAC)—also known as the Krebs cycle or the TCA cycle (tricarboxylic acid cycle)—is a series of chemical reactions to release stored energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins. The Krebs cycle is used by organisms that respire (as opposed to organisms that ferment) to generate energy, either by anaerobic respiration or aerobic respiration. In addition, the cycle provides precursors of certain amino acids, as well as the reducing agent NADH, that are used in numerous other reactions. Its central importance to many biochemical pathways suggests that it was one of the earliest components of metabolism and may have originated abiogenically. Even though it is branded as a 'cycle', it is not necessary for metabolites to follow only one specific route; at least three alternative segments of the citric acid cycle have been recognized. The name of this metabolic pathway is derived from the citric acid (a tricarboxy ... [...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, in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progenitor Cell
A progenitor cell is a Cell (biology), biological cell that can Cellular differentiation, differentiate into a specific cell type. Stem cells and progenitor cells have this ability in common. However, stem cells are less specified than progenitor cells. Progenitor cells can only differentiate into their "target" cell type. The most important difference between stem cells and progenitor cells is that stem cells can replicate indefinitely, whereas progenitor cells can divide only a limited number of times. Controversy about the exact definition remains and the concept is still evolving. The terms "progenitor cell" and "stem cell" are sometimes equated. Properties Most progenitors are identified as Oligopotency, oligopotent. In this point of view, they can compare to adult stem cells, but progenitors are said to be in a further stage of cell differentiation. They are in the "center" between stem cells and fully differentiated cells. The kind of potency they have depends on the type ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neocortex
The neocortex, also called the neopallium, isocortex, or the six-layered cortex, is a set of layers of the mammalian cerebral cortex involved in higher-order brain functions such as sensory perception, cognition, generation of motor commands, spatial reasoning and language. The neocortex is further subdivided into the true isocortex and the proisocortex. In the human brain, the neocortex is the largest part of the cerebral cortex (the outer layer of the cerebrum). The neocortex makes up the largest part of the cerebral cortex, with the allocortex making up the rest. The neocortex is made up of six layers, labelled from the outermost inwards, I to VI. Etymology The term is from ''cortex'', Latin, " bark" or "rind", combined with ''neo-'', Greek, "new". ''Neopallium'' is a similar hybrid, from Latin ''pallium'', "cloak". ''Isocortex'' and ''allocortex'' are hybrids with Greek ''isos'', "same", and ''allos'', "other". Anatomy The neocortex is the most developed in its organisat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenine Nucleotide Translocator
Adenine nucleotide translocator (ANT), also known as the ADP/ATP translocase (ANT), ADP/ATP carrier protein (AAC) or mitochondrial ADP/ATP carrier, exchanges free ATP with free ADP across the inner mitochondrial membrane. ANT is the most abundant protein in the inner mitochondrial membrane and belongs to mitochondrial carrier family. Free ADP is transported from the cytoplasm to the mitochondrial matrix, while ATP produced from oxidative phosphorylation is transported from the mitochondrial matrix to the cytoplasm, thus providing the cells with its main energy currency. ADP/ATP translocases are exclusive to eukaryotes and are thought to have evolved during eukaryogenesis. Human cells express four ADP/ATP translocases: SLC25A4, SLC25A5, SLC25A6 and SLC25A31, which constitute more than 10% of the protein in the inner mitochondrial membrane. These proteins are classified under the mitochondrial carrier superfamily. Types In humans, there exist three paraologous ANT isoforms: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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