ジャーナル: Nucleic Acids Res / 年: 2013 タイトル: Two RNA-binding motifs in eIF3 direct HCV IRES-dependent translation. 著者: Chaomin Sun / Jordi Querol-Audí / Stefanie A Mortimer / Ernesto Arias-Palomo / Jennifer A Doudna / Eva Nogales / Jamie H D Cate / 要旨: The initiation of protein synthesis plays an essential regulatory role in human biology. At the center of the initiation pathway, the 13-subunit eukaryotic translation initiation factor 3 (eIF3) ...The initiation of protein synthesis plays an essential regulatory role in human biology. At the center of the initiation pathway, the 13-subunit eukaryotic translation initiation factor 3 (eIF3) controls access of other initiation factors and mRNA to the ribosome by unknown mechanisms. Using electron microscopy (EM), bioinformatics and biochemical experiments, we identify two highly conserved RNA-binding motifs in eIF3 that direct translation initiation from the hepatitis C virus internal ribosome entry site (HCV IRES) RNA. Mutations in the RNA-binding motif of subunit eIF3a weaken eIF3 binding to the HCV IRES and the 40S ribosomal subunit, thereby suppressing eIF2-dependent recognition of the start codon. Mutations in the eIF3c RNA-binding motif also reduce 40S ribosomal subunit binding to eIF3, and inhibit eIF5B-dependent steps downstream of start codon recognition. These results provide the first connection between the structure of the central translation initiation factor eIF3 and recognition of the HCV genomic RNA start codon, molecular interactions that likely extend to the human transcriptome.
全体 : PCI MPN core of the human eukaryotic translation initiation facto...
全体
名称: PCI MPN core of the human eukaryotic translation initiation factor eIF3 bound to the IIIabc domain of Hepatitis C IRES
要素
試料: PCI MPN core of the human eukaryotic translation initiation factor eIF3 bound to the IIIabc domain of Hepatitis C IRES
タンパク質・ペプチド: eIF3 a
タンパク質・ペプチド: eIF3 c
タンパク質・ペプチド: eIF3 e
タンパク質・ペプチド: eIF3 f
タンパク質・ペプチド: eIF3 h
タンパク質・ペプチド: eIF3 k
タンパク質・ペプチド: eIF3 l
タンパク質・ペプチド: eIF3 m
RNA: IIIabc
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超分子 #1000: PCI MPN core of the human eukaryotic translation initiation facto...
超分子
名称: PCI MPN core of the human eukaryotic translation initiation factor eIF3 bound to the IIIabc domain of Hepatitis C IRES タイプ: sample / ID: 1000 / 詳細: The sample was monodisperse 集合状態: Subcomplex containing 8 core subunits plus IIIabc Number unique components: 9