Probing the cooperativity of Thermoplasma acidophilum proteasome core particle gating by NMR spectroscopy.

ABSTRACT: The 20S proteasome core particle (20S CP) plays an integral role in cellular homeostasis by degrading proteins no longer required for function. The process is, in part, controlled via gating residues localized to the ends of the heptameric barrel-like CP structure that occlude substrate entry pores, preventing unregulated degradation of substrates that might otherwise enter the proteasome. Previously, we showed that the N-terminal residues of the α-subunits of the CP from the archaeon Thermoplasma acidophilum are arranged such that, on average, two of the seven termini are localized inside the lumen of the proteasome, thereby plugging the entry pore and functioning as a gate. However, the mechanism of gating remains unclear. Using solution NMR and a labeling procedure in which a ser

SUBMITTER: Huang R 

PROVIDER: S-EPMC5699070 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature