Download MendeleyStructural basis for nematode eIF4E binding an m2,2,7G-Cap and its implications for translation initiation.
Liu, W., Jankowska-Anyszka, M., Piecyk, K., Dickson, L., Wallace, A., Niedzwiecka, A., Stepinski, J., Stolarski, R., Darzynkiewicz, E., Kieft, J., Zhao, R., Jones, D.N., Davis, R.E.(2011) Nucleic Acids Res 39: 8820-8832
- PubMed: 21965542
- DOI: https://doi.org/10.1093/nar/gkr650
- Primary Citation of Related Structures:
3M93, 3M94 - PubMed Abstract:
Metazoan spliced leader (SL) trans-splicing generates mRNAs with an m(2,2,7)G-cap and a common downstream SL RNA sequence. The mechanism for eIF4E binding an m²²⁷G-cap is unknown. Here, we describe the first structure of an eIF4E with an m(2,2,7)G-cap and compare it to the cognate m⁷G-eIF4E complex. These structures and Nuclear Magnetic Resonance (NMR) data indicate that the nematode Ascaris suum eIF4E binds the two different caps in a similar manner except for the loss of a single hydrogen bond on binding the m(2,2,7)G-cap. Nematode and mammalian eIF4E both have a low affinity for m(2,2,7)G-cap compared with the m⁷G-cap. Nematode eIF4E binding to the m⁷G-cap, m(2,2,7)G-cap and the m(2,2,7)G-SL 22-nt RNA leads to distinct eIF4E conformational changes. Additional interactions occur between Ascaris eIF4E and the SL on binding the m(2,2,7)G-SL. We propose interactions between Ascaris eIF4E and the SL impact eIF4G and contribute to translation initiation, whereas these interactions do not occur when only the m(2,2,7)G-cap is present. These data have implications for the contribution of 5'-UTRs in mRNA translation and the function of different eIF4E isoforms.
Organizational Affiliation:
Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045, USA.
