[2015.1.29] We publish a research paper about the interaction between translationally-controlled tumor protein (TCTP) and eukaryotic elongation factor 1B (eEF1B) onJ. Biol. Chem.

TCTP is a highly conserved abundant protein in eukaryotes and many interaction partners with various functions have been reported. However, no structural information has been reported for these interactions, and many of the reported interactions involve binding partners that are not conserved in eukaryotes, thus may be specific to particular organisms or tissues and cannot be considered primary conserved functions of TCTP. Therefore, the primary function of TCTCP remains unclear. In this paper, we found that that a newly identified central acidic region (CAR) domain of eEF1Bδ is responsible for TCTP binding. We determined the structure of the CAR domain, and identified the binding surfaces of TCTP and the eEF1Bδ CAR domain. The key residues for the binding were confirmed by mutagenesis, and the structure of the complex of TCTP and the eEF1Bδ CAR domain was determined by HADDOCK using chemical shift mapping, paramagnetic relaxation enhancement, and mutagenesis data. We found that the CAR domain is conserved in all GEFs of eEF1B in eukaryotes and the key residues for the binding on TCTP and eEF1B GEFs are also conserved. The interactions were further confirmed using TCTP and eEF1Bα homologues from two lower eukaryotic species (fission yeast and unicellular photosynthetic microalga). Therefore, the interaction of TCTP and eEF1B GEFs is conserved in eukaryotes, implying that TCTP is involved in the protein translation process and that this function represents the primary function of TCTP.

This research is a collaboration between us and Prof. Sarah Perrett group in Institute of Bipohysics, CAS. The research project is supported by Ministry of Science and Technology of China, the National Natural Science Foundation of China , and the Beijing Natural Science Foundation.

NCBI PubMed 

Huiwen Wu, Weibin Gong, Xingzhe Yao, Jinfeng Wang, Sarah Perrett* and Yingang Feng* (2015) Evolutionarily conserved binding of translationally-controlled tumor protein to eukaryotic elongation factor 1B.J. Biol. Chem.290(14), 8694-8710. [Full text (Publisher website)]