A network of assembly factors is involved in remodeling rRNA elements during preribosome maturation.
J Cell Biol
; 207(4): 481-98, 2014 Nov 24.
Article
in En
| MEDLINE
| ID: mdl-25404745
ABSTRACT
Eukaryotic ribosome biogenesis involves â¼200 assembly factors, but how these contribute to ribosome maturation is poorly understood. Here, we identify a network of factors on the nascent 60S subunit that actively remodels preribosome structure. At its hub is Rsa4, a direct substrate of the force-generating ATPase Rea1. We show that Rsa4 is connected to the central protuberance by binding to Rpl5 and to ribosomal RNA (rRNA) helix 89 of the nascent peptidyl transferase center (PTC) through Nsa2. Importantly, Nsa2 binds to helix 89 before relocation of helix 89 to the PTC. Structure-based mutations of these factors reveal the functional importance of their interactions for ribosome assembly. Thus, Rsa4 is held tightly in the preribosome and can serve as a "distribution box," transmitting remodeling energy from Rea1 into the developing ribosome. We suggest that a relay-like factor network coupled to a mechano-enzyme is strategically positioned to relocate rRNA elements during ribosome maturation.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Ribosomal Proteins
/
Saccharomyces cerevisiae
/
RNA, Ribosomal
/
Saccharomyces cerevisiae Proteins
/
Ribosome Subunits, Large, Eukaryotic
Type of study:
Prognostic_studies
Language:
En
Journal:
J Cell Biol
Year:
2014
Document type:
Article
Affiliation country:
Germany