Abstract
Elongation factor eEF3 is an ATPase that, in addition to the two canonical factors eEF1A and eEF2, serves an essential function in the translation cycle of fungi. eEF3 is required for the binding of the aminoacyl-tRNA-eEF1A-GTP ternary complex to the ribosomal A-site and has been suggested to facilitate the clearance of deacyl-tRNA from the E-site. Here we present the crystal structure of Saccharomyces cerevisiae eEF3, showing that it consists of an amino-terminal HEAT repeat domain, followed by a four-helix bundle and two ABC-type ATPase domains, with a chromodomain inserted in ABC2. Moreover, we present the cryo-electron microscopy structure of the ATP-bound form of eEF3 in complex with the post-translocational-state 80S ribosome from yeast. eEF3 uses an entirely new factor binding site near the ribosomal E-site, with the chromodomain likely to stabilize the ribosomal L1 stalk in an open conformation, thus allowing tRNA release.
Publication types
-
Research Support, N.I.H., Extramural
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Adenosine Diphosphate / chemistry
-
Adenosine Diphosphate / metabolism
-
Adenosine Triphosphate / analogs & derivatives
-
Adenosine Triphosphate / metabolism
-
Binding Sites
-
Cryoelectron Microscopy
-
Crystallography, X-Ray
-
Fungal Proteins / chemistry*
-
Fungal Proteins / metabolism*
-
Fungal Proteins / ultrastructure
-
Gene Expression Regulation, Fungal
-
Models, Biological
-
Models, Molecular
-
Peptide Elongation Factors / chemistry*
-
Peptide Elongation Factors / metabolism*
-
Peptide Elongation Factors / ultrastructure
-
Protein Conformation
-
RNA, Transfer / metabolism*
-
Ribosomes / chemistry
-
Ribosomes / metabolism
-
Saccharomyces cerevisiae / chemistry*
-
Saccharomyces cerevisiae Proteins
-
Structure-Activity Relationship
Substances
-
Fungal Proteins
-
Peptide Elongation Factors
-
Saccharomyces cerevisiae Proteins
-
YEF3 protein, S cerevisiae
-
Adenosine Diphosphate
-
Adenosine Triphosphate
-
RNA, Transfer