title: Association of ribosomes with in vitro assembled microtubules.
abstract: Microtubules were purified from unfertilized eggs of the sea urchins Arbacia punctulata, Lytechinus pictus, Lytechinus variegatus, and Strongylocentrotus purpuratus. Numerous densely stained particles (24 x 26 nm) are associated with microtubules isolated from each of these sea urchins. The most striking aspect of this structure is an extended, slightly curved arm that appears to attach the particles to the microtubule. Morphologically similar particles are associated with microtubules of the isolated first cleavage mitotic apparatus. The particles are attached to the microtubules by ionic interactions and contain large amounts of extractable RNA. Based upon their size and density, RNA and protein composition, and sedimentation in sucrose gradients, the microtubule-associated particles are identified as ribosomes.
authors: Department of Physiology and Cell Biology, University of Kansas, Lawrence 66045.
authors: K A
authors: KA
authors: Suprenant
authors: L B
authors: LB
authors: Tempero
authors: L E
authors: LE
authors: Hammer
mesh_terms: D000818:Animals; D002499:Centrifugation, Density Gradient; D004591:Electrophoresis, Polyacrylamide Gel; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D007477:Ions; D008868:Microtubule Proteins / Q000302:isolation & purification; D008869:Microtubule-Associated Proteins / Q000032:analysis; D008870:Microtubules / Q000032:analysis / Q000648:ultrastructure*; D010063:Ovum / Q000648:ultrastructure; D012313:RNA / Q000302:isolation & purification; D012270:Ribosomes / Q000648:ultrastructure*; D012617:Sea Urchins; D008941:Spindle Apparatus / Q000648:ultrastructure
chemical_list: D007477:Ions; D008868:Microtubule Proteins; D008869:Microtubule-Associated Proteins; D012313:RNA