Database of articles cited by EMDB/PDB/SASBDB data

Keywords
Structure methods	All X-ray diffraction NMR electron microscopy small angle scattering neutron diffraction fiber diffraction powder diffraction infrared spectroscopy EPR fluorescence transfer theoretical model Hybrid
Author
Journal
IF	>30 >20 >10 >5 all

Title	The dynamic architecture of Map1- and NatB-ribosome complexes coordinates the sequential modifications of nascent polypeptide chains.
Journal, issue, pages	PLoS Biol, Vol. 21, Issue 4, Page e3001995, Year 2023
Publish date	Apr 20, 2023
Authors	Alexandra G Knorr / Timur Mackens-Kiani / Joanna Musial / Otto Berninghausen / Thomas Becker / Birgitta Beatrix / Roland Beckmann /
PubMed Abstract	Cotranslational modification of the nascent polypeptide chain is one of the first events during the birth of a new protein. In eukaryotes, methionine aminopeptidases (MetAPs) cleave off the starter ...Cotranslational modification of the nascent polypeptide chain is one of the first events during the birth of a new protein. In eukaryotes, methionine aminopeptidases (MetAPs) cleave off the starter methionine, whereas N-acetyl-transferases (NATs) catalyze N-terminal acetylation. MetAPs and NATs compete with other cotranslationally acting chaperones, such as ribosome-associated complex (RAC), protein targeting and translocation factors (SRP and Sec61) for binding sites at the ribosomal tunnel exit. Yet, whereas well-resolved structures for ribosome-bound RAC, SRP and Sec61, are available, structural information on the mode of ribosome interaction of eukaryotic MetAPs or of the five cotranslationally active NATs is only available for NatA. Here, we present cryo-EM structures of yeast Map1 and NatB bound to ribosome-nascent chain complexes. Map1 is mainly associated with the dynamic rRNA expansion segment ES27a, thereby kept at an ideal position below the tunnel exit to act on the emerging substrate nascent chain. For NatB, we observe two copies of the NatB complex. NatB-1 binds directly below the tunnel exit, again involving ES27a, and NatB-2 is located below the second universal adapter site (eL31 and uL22). The binding mode of the two NatB complexes on the ribosome differs but overlaps with that of NatA and Map1, implying that NatB binds exclusively to the tunnel exit. We further observe that ES27a adopts distinct conformations when bound to NatA, NatB, or Map1, together suggesting a contribution to the coordination of a sequential activity of these factors on the emerging nascent chain at the ribosomal exit tunnel.
External links	PLoS Biol / PubMed:37079644 / PubMed Central
Methods	EM (single particle)
Resolution	3.1 - 3.9 Å
Structure data	16086 8bip EMDB-16086, PDB-8bip: Structure of a yeast 80S ribosome-bound N-Acetyltransferase B complex Method: EM (single particle) / Resolution: 3.1 Å 16090 8bjq EMDB-16090, PDB-8bjq: Structure of a yeast 80S ribosome-bound N-Acetyltransferase B complex Method: EM (single particle) / Resolution: 3.8 Å 16182 8bqd EMDB-16182, PDB-8bqd: Yeast 80S ribosome in complex with Map1 (conformation 1) Method: EM (single particle) / Resolution: 3.9 Å 16191 8bqx EMDB-16191, PDB-8bqx: Yeast 80S ribosome in complex with Map1 (conformation 2) Method: EM (single particle) / Resolution: 3.8 Å
Chemicals	ChemComp-MG: Unknown entry ChemComp-ZN: Unknown entry
Source	saccharomyces cerevisiae (brewer's yeast) baker's yeast (brewer's yeast)
Keywords	RIBOSOME / translation / n-acetylation / nascent chain / co-translational modification / NatB / aminopeptidase / Map1