Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.6.4.4 (kinesin)
5,033 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Kinesin is believed to generate force for the movement of organelles in anterograde axonal transport. The identification of genes that encode kinesin-like proteins suggests that other motors may provide anterograde force instead of or in addition to kinesin. To gain insight into the specific functions of kinesin, the effects of mutations in the kinesin heavy chain gene (khc) on the physiology and ultrastructure of Drosophila larval neurons were studied. Mutations in khc impair both action potential propagation in axons and neurotransmitter release at nerve terminals but have no apparent effect on the concentration of synaptic vesicles in nerve terminal cytoplasm. Thus kinesin is required in vivo for normal neuronal function and may be active in the transport of ion channels and components of the synaptic release machinery to their appropriate cellular locations. Kinesin appears not to be required for the anterograde transport of synaptic vesicles or their components.
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PMID:Effects of kinesin mutations on neuronal functions. 138 31

In neuronal axons, various kinds of membranous components are transported along microtubules bidirectionally. However, only two kinds of mechanochemical motor proteins, kinesin and brain dynein, had been identified as transporters of membranous organelles in mammalian neurons. Recently, a series of genes that encode proteins closely related to kinesin heavy chain were identified in several organisms including Schizosaccharomyces pombe, Aspergillus niddulans, Saccharomyces cerevisiae, Caenorhabditus elegans, and Drosophila. Most of these members of the kinesin family are implicated in mechanisms of mitosis or meiosis. To address the mechanism of intracellular organelle transport at a molecular level, we have cloned and characterized five different members (KIF1-5), that encode the microtubule-associated motor domain homologous to kinesin heavy chain, in murine brain tissue. Homology analysis of amino acid sequence indicated that KIF1 and KIF5 are murine counterparts of unc104 and kinesin heavy chain, respectively, while KIF2, KIF3, and KIF4 are as yet unidentified new species. Complete amino acid sequence of KIF3 revealed that KIF3 consists of NH2-terminal motor domain, central alpha-helical rod domain, and COOH-terminal globular domain. Complete amino acid sequence of KIF2 revealed that KIF2 consists of NH2-terminal globular domain, central motor domain, and COOH-terminal alpha-helical rod domain. This is the first identification of the kinesin-related protein which has its motor domain at the central part in its primary structure. Northern blot analysis revealed that KIF1, KIF3, and KIF5 are expressed almost exclusively in murine brain, whereas KIF2 and KIF4 are expressed in brain as well as in other tissues. All these members of the kinesin family are expressed in the same type of neurons, and thus each one of them may transport its specific organelle in the murine central nervous system.
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PMID:Kinesin family in murine central nervous system. 144 3

Kinesin, a microtubule-based force-generating molecule, is thought to translocate organelles along microtubules. To examine the function of kinesin in neurons, we sought to suppress kinesin heavy chain (KHC) expression in cultured hippocampal neurons using antisense oligonucleotides and study the phenotype of these KHC "null" cells. Two different antisense oligonucleotides complementary to the KHC sequence reduced the protein levels of the heavy chain by greater than 95% within 24 h after application and produced identical phenotypes. After inhibition of KHC expression for 24 or 48 h, neurons extended an array of neurites often with one neurite longer than the others; however, the length of all these neurites was significantly reduced. Inhibition of KHC expression also altered the distribution of GAP-43 and synapsin I, two proteins thought to be transported in association with membranous organelles. These proteins, which are normally localized at the tips of growing neurites, were confined to the cell body in antisense-treated cells. Treatment of the cells with the corresponding sense oligonucleotides affected neither the distribution of GAP-43 and synapsin I, nor the length of neurites. A full recovery of neurite length occurred after removal of the antisense oligonucleotides from the medium. These data indicate that KHC plays a role in the anterograde translocation of vesicles containing GAP-43 and synapsin I. A deficiency in vesicle delivery may also explain the inhibition of neurite outgrowth. Despite the inhibition of KHC and the failure of GAP-43 and synapsin I to move out of the cell body, hippocampal neurons can extend processes and acquire as asymmetric morphology.
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PMID:Suppression of kinesin expression in cultured hippocampal neurons using antisense oligonucleotides. 153 97

To understand the interactions between the microtubule-based motor protein kinesin and intracellular components, we have expressed the kinesin heavy chain and its different domains in CV-1 monkey kidney epithelial cells and examined their distributions by immunofluorescence microscopy. For this study, we cloned and sequenced cDNAs encoding a kinesin heavy chain from a human placental library. The human kinesin heavy chain exhibits a high level of sequence identity to the previously cloned invertebrate kinesin heavy chains; homologies between the COOH-terminal domain of human and invertebrate kinesins and the nonmotor domain of the Aspergillus kinesin-like protein bimC were also found. The gene encoding the human kinesin heavy chain also contains a small upstream open reading frame in a G-C rich 5' untranslated region, features that are associated with translational regulation in certain mRNAs. After transient expression in CV-1 cells, the kinesin heavy chain showed both a diffuse distribution and a filamentous staining pattern that coaligned with microtubules but not vimentin intermediate filaments. Altering the number and distribution of microtubules with taxol or nocodazole produced corresponding changes in the localization of the expressed kinesin heavy chain. The expressed NH2-terminal motor and the COOH-terminal tail domains, but not the alpha-helical coiled coil rod domain, also colocalized with microtubules. The finding that both the kinesin motor and tail domains can interact with cytoplasmic microtubules raises the possibility that kinesin could crossbridge and induce sliding between microtubules under certain circumstances.
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PMID:Cloning and expression of a human kinesin heavy chain gene: interaction of the COOH-terminal domain with cytoplasmic microtubules in transfected CV-1 cells. 160 88

To understand the roles of kinesin and its relatives in cell division, it is necessary to identify and characterize multiple members of the kinesin superfamily from mitotic cells. To this end we have raised antisera to peptides corresponding to highly conserved regions of the motor domains of several known members of the kinesin superfamily. These peptide antibodies react specifically with the motor domains of kinesin and ncd protein, as expected, and they also react with several polypeptides (including kinesin heavy chain) that cosediment with microtubules (MTs) precipitated from AMPPNP-treated sea urchin egg cytosol. Subsequent fractionation of ATP eluates of these MTs yields a protein of relative molecular mass 330 x 10(3) that behaves as a complex of three polypeptides that are distinct from conventional kinesin subunits or fragments thereof. This complex contains 85 kDa and 95 kDa polypeptides, which react with our peptide antibodies, and a 115 kDa polypeptide, which does not. This triplet of polypeptides, which we refer to as KRP(85/95), binds to purified sea urchin egg tubulin in an AMPPNP-enhanced, ATP-sensitive manner and induces the formation of microtubule bundles. We therefore propose that the triplet corresponds to a novel sea urchin egg kinesin-related protein.
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PMID:Isolation of a sea urchin egg kinesin-related protein using peptide antibodies. 162 46

To identify kinesin-related proteins that may be important for mitotic function in embryonic and tissue culture cells we have generated polyclonal antibodies to two synthetic peptides corresponding to conserved regions of the kinesin motor domain. In Xenopus eggs we have identified a family of microtubule-binding proteins, recognized by one or both affinity-purified peptide antibodies but not by monoclonal antibodies that recognize conventional kinesin heavy chain. Like kinesin, most of these proteins bind to microtubules only upon addition of AMP-PNP or nucleotide depletion and are released upon subsequent addition of ATP. At least one protein, however, exhibits markedly distinct properties, binding readily to microtubules in the absence of AMP-PNP and/or nucleotide depletion. We also report that, unlike antibodies to conventional kinesin, the peptide antibodies to the kinesin motor domain immunofluorescently label spindles and kinetochores in mitotic tissue culture cells, suggesting that kinesin-like proteins may have important roles in chromosome movement and mitosis.
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PMID:Evidence for kinesin-related proteins in the mitotic apparatus using peptide antibodies. 162 47

Kinesin is a mechanochemical enzyme composed of three distinct domains: a globular head domain, a rodlike stalk domain, and a small globular tail domain. The stalk domain has sequence features characteristic of alpha-helical coiled coils. To gain insight into the structure of the kinesin stalk, we expressed it from a segment of the Drosophila melanogaster kinesin heavy chain gene and purified it from Escherichia coli. When observed by EM, this protein formed a rodlike structure 40-55 nm long that was occasionally bent at a hingelike region near the middle of the molecule. An additional EM study and a chemical cross-linking study showed that this protein forms a parallel dimer and that the two chains are in register. Finally, using circular dichroism spectroscopy, we showed that this protein is approximately 55-60% alpha-helical in physiological aqueous solution at 25 degrees C, and approximately 85-90% alpha-helical at 4 degrees C. From these results, we conclude that the stalk of kinesin heavy chain forms an alpha-helical coiled coil structure. The temperature dependence of the circular dichroism signal has two major transitions, at 25-30 degrees C and at 45-50 degrees C, which suggests that a portion of the alpha-helical structure in the stalk is less stable than the rest. By producing the amino-terminal (coil 1) and carboxy-terminal (coil 2) halves of the stalk separately in E. coli, we showed that the region that melts below 30 degrees C lies within coil 1, while the majority of coil 2 melts above 45 degrees C. We suggest that this difference in stability may play a role in the force-generating mechanism or regulation of kinesin.
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PMID:Evidence that the stalk of Drosophila kinesin heavy chain is an alpha-helical coiled coil. 173 25

Kinesin was previously immunolocalized to mitotic apparatuses (MAs) of early sea urchin blastomeres (Scholey, J.M., M.E. Porter, P.M. Grissom, and J.R. McIntosh. 1985. Nature [Lond.]. 318:483-486). Here we report evidence that this MA-associated motor protein is a conventional membrane-bound kinesin, rather than a kinesin-like protein. Our evidence includes the observation that the deduced amino acid sequence of this sea urchin kinesin heavy chain is characteristic of a conventional kinesin. In addition, immunolocalizations using antibodies that distinguish kinesin from kinesin-like proteins confirm that conventional kinesin is concentrated in MAs. Finally, our immunocytochemical data further suggest that conventional kinesin is associated with membranes which accumulate in MAs and interphase asters of early sea urchin embryos, and with vesicles that are distributed in the perinuclear region of coelomocytes. Thus kinesin may function as a microtubule-based vesicle motor in some MAs, as well as in the interphase cytoplasm.
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PMID:Subcellular localization and sequence of sea urchin kinesin heavy chain: evidence for its association with membranes in the mitotic apparatus and interphase cytoplasm. 182 46

A microtubule-enriched fraction was prepared from bovine white matter, and kinesin and other microtubule-associated proteins were extracted from taxol-stabilized microtubules by homogenization and ultracentrifugation in the presence of nucleotides (guanosine triphosphate and adenosine triphosphate). The kinesin-enriched fractions were subjected to preparative SDS-PAGE, and the band representing the kinesin heavy chain was excised, homogenized, and subjected to partial enzymatic digestion with Staphylococcus aureus V8 protease. Four peptides were selected for sequence analysis and compared to the previously published sequence for the Drosophila kinesin heavy chain (Yang JT, Laymon RA, Goldstein LSB, Cell 56:879-889, 1989). All four peptides matched closely with portions of the Drosophila sequence corresponding to the central, alpha-helical domain. Total amino acid composition analysis of bovine kinesin heavy chain also reveals a high degree of homology to the Drosophila sequence.
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PMID:Kinesin heavy chain from bovine brain and Drosophila appear to be highly homologous molecules. 182 44

Kinesin is a mechanochemical ATPase that induces translocation of latex beads along microtubules and microtubule gliding on a glass surface. This protein is thought to be a motor for the movement of membranous organelles in cells. Recently Hollenbeck and Swanson [Hollenbeck, P. J. & Swanson, J. A. (1990) Nature (London) 346, 864-866] showed that kinesin is involved in the positioning of tubular lysosomes in macrophages. However, the role of this protein in the movement of organelles was not yet clear. We used a polyclonal antibody against the kinesin heavy chain that inhibited kinesin-dependent microtubule gliding in vitro to study the role of kinesin in the movement of pigment granules in melanophores of the teleost black tetra (Gymnocorymbus ternetzi). Microinjection of the antibody into cultured melanophores did not produce any specific effect on the aggregation of pigment granules in melanophores, but it did result in a strong dose-dependent inhibition of the dispersion. Immunoblotting of melanophore extracts showed that the kinesin antibody reacted in these cells with a single protein component with a molecular mass of 135 kDa. Thus, kinesin is responsible for the movement of pigment granules from the center to the periphery of the melanophore.
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PMID:Kinesin is responsible for centrifugal movement of pigment granules in melanophores. 182 87


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