Your browser doesn't support javascript.
loading
Native mass spectrometry analyses of chaperonin complex TRiC/CCT reveal subunit N-terminal processing and re-association patterns.
Collier, Miranda P; Moreira, Karen Betancourt; Li, Kathy H; Chen, Yu-Chan; Itzhak, Daniel; Samant, Rahul; Leitner, Alexander; Burlingame, Alma; Frydman, Judith.
Afiliação
  • Collier MP; Department of Biology, Stanford University, Stanford, CA, USA.
  • Moreira KB; Department of Biology, Stanford University, Stanford, CA, USA.
  • Li KH; Department of Chemistry, University of California San Francisco, San Francisco, CA, USA.
  • Chen YC; Department of Biology, Stanford University, Stanford, CA, USA.
  • Itzhak D; Chan-Zuckerberg BioHub, San Francisco, CA, USA.
  • Samant R; Department of Biology, Stanford University, Stanford, CA, USA.
  • Leitner A; Department of Biology, Institute of Molecular Systems Biology, Zurich, Switzerland.
  • Burlingame A; Department of Chemistry, University of California San Francisco, San Francisco, CA, USA.
  • Frydman J; Department of Biology, Stanford University, Stanford, CA, USA. jfrydman@stanford.edu.
Sci Rep ; 11(1): 13084, 2021 06 22.
Article em En | MEDLINE | ID: mdl-34158536
The eukaryotic chaperonin TRiC/CCT is a large ATP-dependent complex essential for cellular protein folding. Its subunit arrangement into two stacked eight-membered hetero-oligomeric rings is conserved from yeast to man. A recent breakthrough enables production of functional human TRiC (hTRiC) from insect cells. Here, we apply a suite of mass spectrometry techniques to characterize recombinant hTRiC. We find all subunits CCT1-8 are N-terminally processed by combinations of methionine excision and acetylation observed in native human TRiC. Dissociation by organic solvents yields primarily monomeric subunits with a small population of CCT dimers. Notably, some dimers feature non-canonical inter-subunit contacts absent in the initial hTRiC. This indicates individual CCT monomers can promiscuously re-assemble into dimers, and lack the information to assume the specific interface pairings in the holocomplex. CCT5 is consistently the most stable subunit and engages in the greatest number of non-canonical dimer pairings. These findings confirm physiologically relevant post-translational processing and function of recombinant hTRiC and offer quantitative insight into the relative stabilities of TRiC subunits and interfaces, a key step toward reconstructing its assembly mechanism. Our results also highlight the importance of assigning contacts identified by native mass spectrometry after solution dissociation as canonical or non-canonical when investigating multimeric assemblies.
Assuntos

Texto completo: 1 Base de dados: MEDLINE Assunto principal: Chaperonina com TCP-1 Tipo de estudo: Prognostic_studies / Risk_factors_studies Limite: Humans Idioma: En Revista: Sci Rep Ano de publicação: 2021 Tipo de documento: Article País de afiliação: Estados Unidos

Texto completo: 1 Base de dados: MEDLINE Assunto principal: Chaperonina com TCP-1 Tipo de estudo: Prognostic_studies / Risk_factors_studies Limite: Humans Idioma: En Revista: Sci Rep Ano de publicação: 2021 Tipo de documento: Article País de afiliação: Estados Unidos