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)

An antiserum which binds kinesin specifically on Western blots was used to determine the distribution and abundance of chicken kinesin by correlated immunoblotting and immunolocalization. Quantitative immunoblotting showed that the abundance of kinesin varied widely in different cell and tissue types, from 0.039% of total protein in epidermal fibroblasts to 0.309% in sympathetic neurons; of the types examined, only red blood cells lacked detectable kinesin. The molar ratio of tubulin/kinesin varied over a narrower range. To analyze the intracellular distribution of kinesin, cultured fibroblasts were fractionated by sequential extraction with saponin-, Triton X-100-, and SDS-containing buffer. Quantitative blotting of the resulting cell fractions indicated that 68% of fibroblast kinesin is in soluble form, 32% is membrane- or organelle-associated, and none is detectable in cytoskeletal fractions. To visualize this distribution, cells treated by the same extraction protocol were immunofluorescently stained with antikinesin and antitubulin. Without extraction, kinesin staining was located throughout cultured neurons and fibroblasts. However, when fibroblasts were extracted with saponin or Brij 58 before fixation, subsequent staining revealed that the remaining kinesin fraction was colocalized with interphase microtubules, but not with mitotic spindles. Prefixation extraction with Triton abolished antikinesin staining. These data suggest that kinesin may play a role in tubovesicular movement but provide no evidence for a role in mitosis.
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PMID:The distribution, abundance and subcellular localization of kinesin. 252 63

C. elegans contains a microtubule binding protein that resembles both dynein and kinesin. This protein has a MgATPase activity and copurifies on both sucrose gradients and DEAE Sephadex columns with a polypeptide of Mr approximately 400 kd. The ATPase activity is 50% inhibited by 10 microM vanadate, 1 mM N-ethyl maleimide, or 5 mM AMP-PNP; it is enhanced 50% by 0.2% Triton. The 400 kd polypeptide is cleaved at a single site by ultraviolet light in the presence of ATP and vanadate. In these ways, the protein resembles dynein. The protein also promotes ATP-dependent translocation of microtubules or axonemes, "plus" ends trailing. This property is kinesin-like; however, the motility is blocked by 5 microM vanadate, 1 mM N-ethyl maleimide, 0.5 mM ATP-gamma-S, or by ATP-vanadate-UV cleavage of the 400 kd polypeptide, characteristics that differ from kinesin. We propose that this protein is a novel microtubule translocator.
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PMID:Identification of a microtubule-based cytoplasmic motor in the nematode C. elegans. 295 72

Recent studies demonstrate co-localization of kinesin with neurofilament (NF) subunits in culture and suggest that kinesin participates in NF subunit distribution. We sought to determine whether kinesin was also associated with NF subunits in situ. Axonal transport of NF subunits in mouse optic nerve was perturbed by the microtubule (MT)-depolymerizing drug vinblastine, indicating that NF transport was dependent upon MT dynamics. Kinesin co-precipitated during immunoprecipitation of NF subunits from optic nerve. The association of NFs and kinesin was regulated by NF phosphorylation, since (1) NF subunits bearing developmentally delayed phospho-epitopes did not co-purify in a microtubule motor preparation from CNS while less phosphorylated forms did; (2) subunits bearing these phospho-epitopes were selectively not co-precipitated with kinesin; and (3) phosphorylation under cell-free conditions diminished the association of NF subunits with kinesin. The nature and extent of this association was further examined by intravitreal injection of (35)S-methionine and monitoring NF subunit transport along optic axons. As previously described by several laboratories, the wave of NF subunits underwent a progressive broadening during continued transport. The front, but not the trail, of this broadening wave of NF subunits was co-precipitated with kinesin, indicating that (1) the fastest-moving NFs were associated with kinesin, and (2) that dissociation from kinesin may foster trailing of NF subunits during continued transport. These data suggest that kinesin participates in NF axonal transport either by directly translocating NFs and/or by linking NFs to transporting MTs. Both Triton-soluble as well as cytoskeleton-associated NF subunits were co-precipitated with kinesin; these data are considered in terms of the form(s) in which NF subunits undergo axonal transport.
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PMID:Phospho-dependent association of neurofilament proteins with kinesin in situ. 1074 58

The guided gliding of cytoskeletal filaments, driven by biomolecular motors on nano/microstructured chips, enables novel applications in biosensing and biocomputation. However, expensive and time-consuming chip production hampers the developments. It is therefore important to establish protocols to regenerate the chips, preferably without the need to dismantle the assembled microfluidic devices which contain the structured chips. We here describe a novel method toward this end. Specifically, we use the small, nonselective proteolytic enzyme, proteinase K to cleave all surface-adsorbed proteins, including myosin and kinesin motors. Subsequently, we apply a detergent (5% SDS or 0.05% Triton X100) to remove the protein remnants. After this procedure, fresh motor proteins and filaments can be added for new experiments. Both, silanized glass surfaces for actin-myosin motility and pure glass surfaces for microtubule-kinesin motility were repeatedly regenerated using this approach. Moreover, we demonstrate the applicability of the method for the regeneration of nano/microstructured silicon-based chips with selectively functionalized areas for supporting or suppressing gliding motility for both motor systems. The results substantiate the versatility and a promising broad use of the method for regenerating a wide range of protein-based nano/microdevices.
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PMID:Regeneration of Assembled, Molecular-Motor-Based Bionanodevices. 3151 80