Dominant Rio1 kinase/ATPase catalytic mutant induces trapping of late pre-40S biogenesis factors in 80S-like ribosomes.

ABSTRACT: During eukaryotic ribosome biogenesis, members of the conserved atypical serine/threonine protein kinase family, the RIO kinases (Rio1, Rio2 and Rio3) function in small ribosomal subunit biogenesis. Structural analysis of Rio2 indicated a role as a conformation-sensing ATPase rather than a kinase to regulate its dynamic association with the pre-40S subunit. However, it remained elusive at which step and by which mechanism the other RIO kinase members act. Here, we have determined the crystal structure of the human Rio1-ATP-Mg(2+) complex carrying a phosphoaspartate in the active site indicative of ATPase activity. Structure-based mutations in yeast showed that Rio1's catalytic activity regulates its pre-40S association. Furthermore, we provide evidence that Rio1 associates with a very late

SUBMITTER: Ferreira-Cerca S 

PROVIDER: S-EPMC4117770 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature