Phosphorylation and aggregation of neurotubulin and ‘associated’ protein-kinase

摘要: Abstract The results reported in this work show that: 1. 1) protein-kinase copurified with brain tubulin differs from the soluble enzyme as demonstrated by: higher elution molarity DEAE-Sephadex A-50, relative affinities for various protein substrates, susceptibility to cAMP activation, apparent K M nucleotide and effect of Ca 2+ . Moreover, ‘associated’ neurotubular enzymatic activity is not intrinsic molecule since it was partially separated by sucrose gradient ultracentrifugation 6 S subunit completely aggregates. 2. 2) cAMP-dependent phosphorylate vitro microtubular protein. After incubation (γ- 32 P) ATP purified preparation, only aggregates are labelled. polydisperse peak heterogeneously phosphorylated, specific ( P/protein) varying along ultraeentrifugation profile. Labelled may be dissociated urea-MSH yielding two chains both labelled P. These have some significance regulation process assembly disassembly microtubules therefore functional role these cellular structures neurosecretory processes.