title: A microtubule-associated protein specific to differentiated neuroblastoma cells.
abstract: A modified procedure is reported that enables microtubule assembly to occur in extracts of differentiated neuroblastoma cells. Of the proteins that co-assemble through five successive cycles, only two, with molecular weights of 215,000 and 71,000, are retained in constant ratio to tubulin. The 215,000-dalton protein is quantitatively sedimented with microtubules during later cycles of assembly, whereas the 71,000-dalton protein is distributed between assembling and nonassembling fractions. Similar procedures do not induce assembly for microtubules from nondifferentiated neuroblastoma cells. Two-dimensional gel analyses indicate that the differentiated cell extracts contain the 215,000-dalton protein. In contrast, gels of extracts from nondifferentiated cells show no protein in the equivalent region. These data suggest that the 215,000-dalton protein is a microtubule-associated protein that may play a role in microtubule-dependent neurite differentiation.
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002460:Cell Line; D051379:Mice; D008869:Microtubule-Associated Proteins; D008870:Microtubules / Q000502:physiology*; D008970:Molecular Weight; D009419:Nerve Tissue Proteins / Q000302:isolation & purification / Q000502:physiology*; D009447:Neuroblastoma / Q000503:physiopathology*; D011506:Proteins / Q000302:isolation & purification / Q000502:physiology*
chemical_list: D008869:Microtubule-Associated Proteins; D009419:Nerve Tissue Proteins; D011506:Proteins