Summary information and primary citation
- PDB-id
- 6yal; SNAP-derived features in text and JSON formats;
DNAproDB
- Class
- translation
- Method
- cryo-EM (3.0 Å)
- Summary
- Mammalian 48s late-stage initiation complex with beta-globin mrna
- Reference
- Simonetti A, Guca E, Bochler A, Kuhn L, Hashem Y (2020): "Structural Insights into the Mammalian Late-Stage Initiation Complexes." Cell Rep, 31, 107497. doi: 10.1016/j.celrep.2020.03.061.
- Abstract
- In higher eukaryotes, the mRNA sequence in the direct vicinity of the start codon, called the Kozak sequence (CRCCaugG, where R is a purine), is known to influence the rate of the initiation process. However, the molecular basis underlying its role remains poorly understood. Here, we present the cryoelectron microscopy (cryo-EM) structures of mammalian late-stage 48S initiation complexes (LS48S ICs) in the presence of two different native mRNA sequences, β-globin and histone 4, at overall resolution of 3 and 3.5 Å, respectively. Our high-resolution structures unravel key interactions from the mRNA to eukaryotic initiation factors (eIFs): 1A, 2, 3, 18S rRNA, and several 40S ribosomal proteins. In addition, we are able to study the structural role of ABCE1 in the formation of native 48S ICs. Our results reveal a comprehensive map of ribosome/eIF-mRNA and ribosome/eIF-tRNA interactions and suggest the impact of mRNA sequence on the structure of the LS48S IC.