Bead movement by single kinesin molecules studied with optical tweezers Export

@article{citeulike:3751328, abstract = {Kinesin, a mechanoenzyme that couples ATP hydrolysis to movement along microtubules, is thought to power vesicle transport and other forms of microtubule-based motility. Here, microscopic silica beads were precoated with carrier protein, exposed to low concentrations of kinesin, and individually manipulated with a single-beam gradient-force optical particle trap ('optical tweezers') directly onto microtubules. Optical tweezers greatly improved the efficiency of the bead assay, particularly at the lowest kinesin concentrations (corresponding to approximately 1 molecule per bead). Beads incubated with excess kinesin moved smoothly along a microtubule for many micrometres, but beads carrying from 0.17-3 kinesin molecules per bead, moved, on average, only about 1.4 microns and then spontaneously released from the microtubule. Application of the optical trap directly behind such moving beads often pulled them off the microtubule and back into the centre of the trap. This did not occur when a bead was bound by an AMP.PNP-induced rigor linkage, or when beads were propelled by several kinesin molecules. Our results are consistent with a model in which kinesin detaches briefly from the microtubule during a part of each mechanochemical cycle, rather than a model in which kinesin remains bound at all times.}, author = {Block, Steven M. and Goldstein, Lawrence S. B. and Schnapp, Bruce J.}, citeulike-article-id = {3751328}, citeulike-linkout-0 = {http://dx.doi.org/10.1038/348348a0}, citeulike-linkout-1 = {http://dx.doi.org/10.1038/348348a0}, citeulike-linkout-2 = {http://view.ncbi.nlm.nih.gov/pubmed/2174512}, citeulike-linkout-3 = {http://www.hubmed.org/display.cgi?uids=2174512}, comment = {Classic bead motility assay / optical tweezers kinesin paper.}, day = {22}, doi = {10.1038/348348a0}, issn = {0028-0836}, journal = {Nature}, keywords = {assay, bead, bma, dtra, kinesin, motility}, month = {November}, number = {6299}, pages = {348--352}, posted-at = {2009-04-27 05:09:18}, priority = {0}, publisher = {Nature Publishing Group}, title = {Bead movement by single kinesin molecules studied with optical tweezers}, url = {http://dx.doi.org/10.1038/348348a0}, volume = {348}, year = {1990} }

TY - JOUR ID - citeulike:3751328 L3 - citeulike-article-id:3751328 N2 - Kinesin, a mechanoenzyme that couples ATP hydrolysis to movement along microtubules, is thought to power vesicle transport and other forms of microtubule-based motility. Here, microscopic silica beads were precoated with carrier protein, exposed to low concentrations of kinesin, and individually manipulated with a single-beam gradient-force optical particle trap ('optical tweezers') directly onto microtubules. Optical tweezers greatly improved the efficiency of the bead assay, particularly at the lowest kinesin concentrations (corresponding to approximately 1 molecule per bead). Beads incubated with excess kinesin moved smoothly along a microtubule for many micrometres, but beads carrying from 0.17-3 kinesin molecules per bead, moved, on average, only about 1.4 microns and then spontaneously released from the microtubule. Application of the optical trap directly behind such moving beads often pulled them off the microtubule and back into the centre of the trap. This did not occur when a bead was bound by an AMP.PNP-induced rigor linkage, or when beads were propelled by several kinesin molecules. Our results are consistent with a model in which kinesin detaches briefly from the microtubule during a part of each mechanochemical cycle, rather than a model in which kinesin remains bound at all times. IS - 6299 JF - Nature SN - 0028-0836 EP - 352 TI - Bead movement by single kinesin molecules studied with optical tweezers PB - Nature Publishing Group VL - 348 SP - 348 KW - assay KW - bead KW - bma KW - dtra KW - kinesin KW - motility N1 - Classic bead motility assay / optical tweezers kinesin paper. AU - Block, Steven AU - Goldstein, Lawrence AU - Schnapp, Bruce PY - 1990/11/22/ UR - http://dx.doi.org/10.1038/348348a0 ER -