Molecular mechanism of cargo recognition and handover by the mammalian signal recognition particle.

ABSTRACT: Co-translational protein targeting to membranes by the signal recognition particle (SRP) is a universally conserved pathway from bacteria to humans. In mammals, SRP and its receptor (SR) have many additional RNA features and protein components compared to the bacterial system, which were recently shown to play regulatory roles. Due to its complexity, the mammalian SRP targeting process is mechanistically not well understood. In particular, it is not clear how SRP recognizes translating ribosomes with exposed signal sequences and how the GTPase activity of SRP and SR is regulated. Here, we present electron cryo-microscopy structures of SRP and SRP·SR in complex with the translating ribosome. The structures reveal the specific molecular interactions between SRP and the emerging signal sequen

SUBMITTER: Jomaa A 

PROVIDER: S-EPMC8330425 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature