6Q8Y

Cryo-EM structure of the mRNA translating and degrading yeast 80S ribosome-Xrn1 nuclease complex

This is a non-PDB format compatible entry.

Summary for 6Q8Y

• Entry DOI: 10.2210/pdb6q8y/pdb
• EMDB information: 4474
• Descriptor: 18S ribosomal RNA, 60S ribosomal protein L38, 60S ribosomal protein L13-A, ... (84 entities in total)
• Functional Keywords: ribosome, stalling, translation, nuclease, exoribonuclease, xrn1
• Biological source: Saccharomyces cerevisiae; More
• Total number of polymer chains: 82
• Total formula weight: 3180012.67

Authors

Tesina, P.,Heckel, E.,Cheng, J.,Buschauer, R.,Kater, L.,Berninghausen, O.,Becker, T.,Beckmann, R. (deposition date: 2018-12-16, release date: 2019-03-13, Last modification date: 2025-12-17)

Primary citation

Tesina, P.,Heckel, E.,Cheng, J.,Fromont-Racine, M.,Buschauer, R.,Kater, L.,Beatrix, B.,Berninghausen, O.,Jacquier, A.,Becker, T.,Beckmann, R.
Structure of the 80S ribosome-Xrn1 nuclease complex.
Nat.Struct.Mol.Biol., 26:275-280, 2019

PubMed Abstract: Messenger RNA (mRNA) homeostasis represents an essential part of gene expression, in which the generation of mRNA by RNA polymerase is counter-balanced by its degradation by nucleases. The conserved 5'-to-3' exoribonuclease Xrn1 has a crucial role in eukaryotic mRNA homeostasis by degrading decapped or cleaved mRNAs post-translationally and, more surprisingly, also co-translationally. Here we report that active Xrn1 can directly and specifically interact with the translation machinery. A cryo-electron microscopy structure of a programmed Saccharomyces cerevisiae 80S ribosome-Xrn1 nuclease complex reveals how the conserved core of Xrn1 enables binding at the mRNA exit site of the ribosome. This interface provides a conduit for channelling of the mRNA from the ribosomal decoding site directly into the active center of the nuclease, thus separating mRNA decoding from degradation by only 17 ± 1 nucleotides. These findings explain how rapid 5'-to-3' mRNA degradation is coupled efficiently to its final round of mRNA translation.

PubMed: 30911188
DOI: 10.1038/s41594-019-0202-5

Experimental method

ELECTRON MICROSCOPY (3.1 Å)