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Monastrol
Monastrol is a cell-permeable small molecule inhibitor discovered by Thomas U. Mayer in the lab of Tim Mitchison. Monastrol was shown to inhibit the kinesin-5 (also known as KIF11, Kinesin Eg5), a motor protein Motor proteins are a class of molecular motors that can move along the cytoskeleton of cells. They do this by converting chemical energy into mechanical work by the hydrolysis of ATP. Cellular functions Motor proteins are the driving force b ... important for spindle bipolarity. Mechanism of action Monastrol binds to a long loop that is specific to the Eg5 (also known as KIF11 or kinesin-5) kinesin family, and allosterically inhibits ATPase activity of the kinesin References GABAA receptor positive allosteric modulators GHB receptor agonists Thioureas Pyrimidines 3-Hydroxyphenyl compounds {{pharma-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tim Mitchison
Timothy John Mitchison is a cell biologist and systems biologist and Hasib Sabbagh Professor of Systems Biology at Harvard Medical School in the United States. He is known for his discovery, with Marc Kirschner, of dynamic instability in microtubules, for studies of the mechanism of cell division, and for contributions to chemical biology. Education and early life Mitchison was educated at Haberdashers' Aske's Boys' School and completed his Bachelor of Arts degree in Biochemistry at the University of Oxford where he was an undergraduate student of Merton College, Oxford, from 1976 to 1979. He moved to the University of California, San Francisco (UCSF) in 1979 for his PhD which was supervised by Marc Kirschner and investigated the dynamic instability of microtubules. Career and research Mitchison returned to the UK for postdoctoral research at the National Institute for Medical Research (NIMR) in London. In 1988 he returned to San Francisco where he was appointed assistant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinesin
A kinesin is a protein complex belonging to a class of motor proteins found in eukaryotic cells. Kinesins move along microtubule (MT) filaments and are powered by the hydrolysis of adenosine triphosphate (ATP) (thus kinesins are ATPases, a type of enzyme). The active movement of kinesins supports several cellular functions including mitosis, meiosis and transport of cellular cargo, such as in axonal transport, and intraflagellar transport. Most kinesins walk towards the plus end of a microtubule, which, in most cells, entails transporting cargo such as protein and membrane components from the center of the cell towards the periphery. This form of transport is known as anterograde transport. In contrast, dyneins are motor proteins that move toward the minus end of a microtubule in retrograde transport. Discovery The first kinesins to be discovered were microtubule-based anterograde intracellular transport motors in 1985, based on their motility in cytoplasm extruded from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motor Protein
Motor proteins are a class of molecular motors that can move along the cytoskeleton of cells. They do this by converting chemical energy into mechanical work by the hydrolysis of ATP. Cellular functions Motor proteins are the driving force behind most active transport of proteins and vesicles in the cytoplasm. Kinesins and cytoplasmic dyneins play essential roles in intracellular transport such as axonal transport and in the formation of the spindle apparatus and the separation of the chromosomes during mitosis and meiosis. Axonemal dynein, found in cilia and flagella, is crucial to cell motility, for example in spermatozoa, and fluid transport, for example in trachea. The muscle protein myosin "motors" the contraction of muscle fibers in animals. Diseases associated with motor protein defects The importance of motor proteins in cells becomes evident when they fail to fulfill their function. For example, kinesin deficiencies have been identified as the cause for Cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GABAA Receptor Positive Allosteric Modulators
In pharmacology, GABAA receptor positive allosteric modulators, also known as GABAkines or GABAA receptor potentiators, are positive allosteric modulator (PAM) molecules that increase the activity of the GABAA receptor, GABAA receptor protein in the vertebrate central nervous system. GABA is a major inhibitory neurotransmitter in the central nervous system. Upon binding, it Agonist, triggers the GABAA receptor to open its GABAA receptor#Structure and function, chloride channel to allow Chloride, chloride ions into the neuron, making the cell Hyperpolarization (biology), hyperpolarized and less likely to Action potential, fire. GABAA PAMs increase the effect of GABA by making the channel open more frequently or for longer periods. However, they have no effect if GABA or another agonist is not present. Unlike GABA receptor agonist, GABAA receptor agonists, GABAA PAMs do not bind at the same active site as the γ-aminobutyric acid (GABA) neurotransmitter molecule: they affect the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thioureas
In organic chemistry, thioureas are members of a family of organosulfur compounds with the formula and structure . The parent member of this class of compounds is thiourea (). Substituted thioureas are found in several commercial chemicals. Structure and bonding Thioureas have a trigonal planar molecular geometry of the core. The bond distance is near 1.71 Å, which is 0.1 Å longer than in normal ketones (). The C–N bond distances are short. Thioureas occurs in two tautomeric forms. : On the other hand, some compounds depicted as isothioureas and in fact thioureas, one example being mercaptobenzimidazole. Synthesis ''N'',''N''′-unsubstituted thioureas can be prepared by treating the corresponding cyanamide with hydrogen sulfide or similar sulfide sources. Organic ammonium salts react with potassium thiocyanate as the source of the thiocarbonyl (). Alternatively, ''N'',''N''′-disubstituted thioureas can be prepared by coupling two amines with thiophosgen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrimidines
Pyrimidine (; ) is an aromatic, heterocyclic, organic compound similar to pyridine (). One of the three diazines (six-membered heterocyclics with two nitrogen atoms in the ring), it has nitrogen atoms at positions 1 and 3 in the ring. The other diazines are pyrazine (nitrogen atoms at the 1 and 4 positions) and pyridazine (nitrogen atoms at the 1 and 2 positions). In nucleic acids, three types of nucleobases are pyrimidine derivatives: cytosine (C), thymine (T), and uracil (U). Occurrence and history The pyrimidine ring system has wide occurrence in nature as substituted and ring fused compounds and derivatives, including the nucleotides cytosine, thymine and uracil, thiamine (vitamin B1) and alloxan. It is also found in many synthetic compounds such as barbiturates and the HIV drug zidovudine. Although pyrimidine derivatives such as alloxan were known in the early 19th century, a laboratory synthesis of a pyrimidine was not carried out until 1879, when Grimaux reported the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
