1H, 13C, and 15N backbone chemical shift assignments of 4E-BP144–87 and 4E-BP144–87 bound to eIF4E

Abstract

The eukaryotic translational initiation factor 4G (eIF4G) interacts with the cap-binding protein eIF4E through a consensus binding motif, Y(X)4LΦ (where X is any amino acid and Φ is a hydrophobic residue). 4E binding proteins (4E-BPs), which also contain a Y(X)4LΦ motif, regulate the eIF4E/eIF4G interaction. The non- or minimally-phosphorylated form of 4E-BP1 binds eIF4E, preventing eIF4E from interacting with eIF4G, thus inhibiting translation initiation. 4EGI-1, a small molecule inhibitor of the eIF4E/eIF4G interaction that is under investigation as a novel anti-cancer drug, has a dual activity; it disrupts the eIF4E/eIF4G interaction and stabilizes the binding of 4E-BP1 to eIF4E. Here, we report the complete backbone NMR resonance assignment of an unliganded 4E-BP1 fragment (4E-BP144–87). We also report the near complete backbone assignment of the same fragment in complex to eIF4E/m7GTP (excluding the assignment of the last C-terminus residue, D87). The chemical shift data constitute a prerequisite to understanding the mechanism of action of translation initiation inhibitors, including 4EGI-1, that modulate the eIF4E/4E-BP1 interaction.

The human eIF4E:4E-BP2 complex structure for studying hyperphosphorylation

“…1), which has also been observed by NMR experiments. 69 There is one stable HBond between H78 4E and the residue at Y +29 in eIF4G (L641 4G ), 4E-BP1 (S83 BP1 ) and 4E-BP3 (T69 BP3 ). In eIF4G, N645 4G (Y +33 ) forms another two HBonds with N77 4E and H78 4E observed in one of three simulations.…”