The DEAD-box Protein Rok1 Orchestrates 40S and 60S Ribosome Assembly by Promoting the Release of Rrp5 from Pre-40S Ribosomes to Allow for 60S Maturation.

ABSTRACT: DEAD-box proteins are ubiquitous regulators of RNA biology. While commonly dubbed "helicases," their activities also include duplex annealing, adenosine triphosphate (ATP)-dependent RNA binding, and RNA-protein complex remodeling. Rok1, an essential DEAD-box protein, and its cofactor Rrp5 are required for ribosome assembly. Here, we use in vivo and in vitro biochemical analyses to demonstrate that ATP-bound Rok1, but not adenosine diphosphate (ADP)-bound Rok1, stabilizes Rrp5 binding to 40S ribosomes. Interconversion between these two forms by ATP hydrolysis is required for release of Rrp5 from pre-40S ribosomes in vivo, thereby allowing Rrp5 to carry out its role in 60S subunit assembly. Furthermore, our data also strongly suggest that the previously described accumulation of snR30 upon R

SUBMITTER: Khoshnevis S 

PROVIDER: S-EPMC4900678 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature