eIF4G is an important scaffold for the eIF4F complex and aids in recruiting the 40S ribosomal subunit to mRNA. There are three mechanisms that the 40S ribosome can come to recognize the start codon: scanning, internal entry, and shunting .

eIF4G（eukaryotic translation initiation factor 4G，真核起始因子4G）是一种在真核翻译起始进程中发挥重要作用的蛋白质。 它主要是在轉譯起始早期协同不同起始因子间的作用和增强它们的活性（包括 eIF4E 的帽结合活性， eIF4A 的 RNA 解旋酶 活性， PABP 的poly-A结合活性 ...

2024年4月4日 · Messenger RNA (mRNA) recruitment to the 40S ribosomal subunit is mediated by eukaryotic initiation factor 4F (eIF4F). This complex includes 3 subunits: eIF4E (m 7 G cap binding protein), eIF4A (DEAD-box helicase), and eIF4G. Mammalian eIF4G is a scaffold that coordinates the activities of e …

2024年5月1日 · eIF4G binds to the 40S subunit through multiple contacts. Human eIF4G uses multiple interactions to form a molecular bridge that connects the eIF4F cap-binding complex and the 40S subunit. An eIF3-specific binding domain (colored green) in human eIF4G indirectly stabilizes eIF4G on the 40S subunit.

More importantly, eIF4G was proposed as indirectly recruiting the 40S subunit of the ribosome through their respective interaction with eIF3. Here, we show through different approaches that the small ribosomal subunit can be directly recruited by EMCV IRES, with no need for initiation factors or for ITAF.

Inhibiting expression of eukaryotic translation initiation factor 4G (eIF4G) arrests normal development but extends lifespan when suppressed during adulthood. In addition to reducing overall translation, inhibition alters the stoichiometry of mRNA ...

2013年11月15日 · In mammals, the direct interaction between eukaryotic initiation factor 4G (eIF4G) and eIF3 is thought to act as the molecular bridge between the mRNA cap-binding complex and the 40S subunit. A discrete ∼90 amino acid domain in eIF4G is responsible for binding to eIF3, but the identity of the eIF3 subunit(s) involved is less clear.

2023年9月29日 · Messenger RNA (mRNA) recruitment to the 40S ribosomal subunit is mediated by eukaryotic initiation factor 4F (eIF4F). This complex includes 3 subunits: eIF4E (m 7 G cap binding protein), eIF4A (DEAD box helicase), and eIF4G. Mammalian eIF4G is a scaffold that coordinates the activities of eIF4E and eIF4A and provides a bridge to connect the ...

2023年9月30日 · Mammalian eIF4G is a scaffold that coordinates the activities of eIF4E and eIF4A and provides a bridge to connect the mRNA and 40S ribosomal subunit through its interaction with eIF3. While the roles of many eIF4G binding domains are relatively clear, the precise function of RNA binding by eIF4G remains to be elucidated.

Here we demonstrate that, in contrast with the current model, the molecular mechanism of EMCV-IRES involves direct recruitment of the 40S subunit. Importantly, we identified a specific structural element that prevents the correct positioning of the initiation codon in the close vicinity of the ribosomal P site.