Cryo-electron microscopy structure of an archaeal ribonuclease P holoenzyme.
Nat Commun
; 10(1): 2617, 2019 06 13.
Article
em En
| MEDLINE
| ID: mdl-31197137
ABSTRACT
Ribonuclease P (RNase P) is an essential ribozyme responsible for tRNA 5' maturation. Here we report the cryo-EM structures of Methanocaldococcus jannaschii (Mja) RNase P holoenzyme alone and in complex with a tRNA substrate at resolutions of 4.6 Å and 4.3 Å, respectively. The structures reveal that the subunits of MjaRNase P are strung together to organize the holoenzyme in a dimeric conformation required for efficient catalysis. The structures also show that archaeal RNase P is a functional chimera of bacterial and eukaryal RNase Ps that possesses bacterial-like two RNA-based anchors and a eukaryal-like protein-aided stabilization mechanism. The 3'-RCCA sequence of tRNA, which is a key recognition element for bacterial RNase P, is dispensable for tRNA recognition by MjaRNase P. The overall organization of MjaRNase P, particularly within the active site, is similar to those of bacterial and eukaryal RNase Ps, suggesting a universal catalytic mechanism for all RNase Ps.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Proteínas Arqueais
/
Ribonuclease P
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article