Dynamics of group II chaperonin and prefoldin probed by 13C NMR spectroscopy.
Group II chaperonin (CPN) cooperates with prefoldin (PFD), which forms a jellyfish-shaped heterohexameric complex with a molecular mass of 87 kDa. PFD captures an unfolded protein with the tentacles and transfers it to the cavity of CPN. Although X-ray crystal structures of CPN and PFD have been reported, no structural information has been so far available for the terminal regions of the PFD tentacles nor for the C-terminal segments of CPNs, which were regarded to be functionally significant in the previous studies. Here we report 13C NMR analyses on archaeal PFD, CPN, and their complex, focusing on those structurally uncharacterized regions. The PFD and CPN complexes selectively labeled with 13C at methionyl carbonyl carbons were separately and jointly subjected to NMR measurements. 13C NMR spectral data demonstrated that the N-terminal segment of the alpha and beta subunits of PFD as well as the C-terminal segments of the CPN hexadecamer retain significant degrees of freedom in internal motion even in the complex with a molecular mass of 1.1 MDa.
Kurimoto
Eiji
E
Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan.
Nishi
Yohei
Y
Yamaguchi
Yoshiki
Y
Zako
Tamotsu
T
Iizuka
Ryo
R
Ide
Naoki
N
Yohda
Masafumi
M
Kato
Koichi
K
D019843:Archaeal Proteins / Q000737:chemistry; D002247:Carbon Isotopes; D018833:Chaperonins / Q000737:chemistry*; D018832:Molecular Chaperones / Q000737:chemistry*; D046912:Multiprotein Complexes / Q000737:chemistry; D019906:Nuclear Magnetic Resonance, Biomolecular; D011487:Protein Conformation; D021122:Protein Subunits; D043902:Pyrococcus horikoshii / Q000737:chemistry*
D019843:Archaeal Proteins; D002247:Carbon Isotopes; D018832:Molecular Chaperones; D046912:Multiprotein Complexes; D021122:Protein Subunits; C112806:prefoldin; D018833:Chaperonins