9F1B

Mammalian ternary complex of a translating 80S ribosome, NAC and NatA/E

This is a non-PDB format compatible entry.

Summary for 9F1B

• Entry DOI: 10.2210/pdb9f1b/pdb
• Related: 6ppl 7qwr 8p2k
• EMDB information: 50124
• Descriptor: Large ribosomal subunit protein uL22, Large ribosomal subunit protein eL18, 40S ribosomal protein S19, ... (97 entities in total)
• Functional Keywords: translation, ribosome, n-terminal acetyltransferase, nata, nate, nac
• Biological source: Homo sapiens (human); More
• Total number of polymer chains: 89
• Total formula weight: 4100333.85

Authors

Yudin, D.,Scaiola, A.,Ban, N. (deposition date: 2024-04-18, release date: 2024-08-21, Last modification date: 2024-10-02)

Primary citation

Lentzsch, A.M.,Yudin, D.,Gamerdinger, M.,Chandrasekar, S.,Rabl, L.,Scaiola, A.,Deuerling, E.,Ban, N.,Shan, S.O.
NAC guides a ribosomal multienzyme complex for nascent protein processing.
Nature, 633:718-724, 2024

PubMed Abstract: Approximately 40% of the mammalian proteome undergoes N-terminal methionine excision and acetylation, mediated sequentially by methionine aminopeptidase (MetAP) and N-acetyltransferase A (NatA), respectively. Both modifications are strictly cotranslational and essential in higher eukaryotic organisms. The interaction, activity and regulation of these enzymes on translating ribosomes are poorly understood. Here we perform biochemical, structural and in vivo studies to demonstrate that the nascent polypeptide-associated complex (NAC) orchestrates the action of these enzymes. NAC assembles a multienzyme complex with MetAP1 and NatA early during translation and pre-positions the active sites of both enzymes for timely sequential processing of the nascent protein. NAC further releases the inhibitory interactions from the NatA regulatory protein huntingtin yeast two-hybrid protein K (HYPK) to activate NatA on the ribosome, enforcing cotranslational N-terminal acetylation. Our results provide a mechanistic model for the cotranslational processing of proteins in eukaryotic cells.

PubMed: 39169182
DOI: 10.1038/s41586-024-07846-7

Experimental method

ELECTRON MICROSCOPY (3.01 Å)