New insights on the interaction between the isoforms 1 and 2 of human translation elongation factor 1A

Area of Science:

• Molecular Biology
• Cell Biology

Background:

• The eukaryotic translation elongation factor 1A (eEF1A) is a moonlighting protein involved in protein synthesis, cell survival, and apoptosis.
• Previous research identified eEF1A phosphorylation sites regulating its half-life and cancer cell apoptosis, suggesting a role for eEF1A isoforms.

Purpose of the Study:

• To investigate the cellular localization and interaction between the two eEF1A isoforms, eEF1A1 and eEF1A2.
• To explore the potential formation of regulatory eEF1A heterodimers.

Main Methods:

• Development of fluorescent chimera proteins by fusing mCerulean and mVenus to the N-termini of eEF1A1 and eEF1A2, respectively.
• Expression of these fluorescent chimeras in COS-7 cells.
• Utilizing Förster Resonance Energy Transfer (FRET) to detect interactions between labeled eEF1A isoforms.

Main Results:

• Fluorescently labeled eEF1A1 and eEF1A2 were found to co-localize in the cytoplasm, specifically at cellular membranes.
• Förster Resonance Energy Transfer (FRET) was detected between the N-termini of the eEF1A isoforms.
• Intra-molecular FRET within the chimera constructs reached approximately 17%.

Conclusions:

• The study provides novel information regarding the intracellular distribution and interaction of eEF1A isoforms.
• Co-localization and FRET suggest a physical interaction between eEF1A1 and eEF1A2, supporting the hypothesis of regulatory heterodimer formation.