Eukaryotic elongation factor-2 (eEF2): its regulation and peptide chain elongation.

Area of Science:

• Molecular Biology
• Cellular Biology
• Biochemistry

Background:

• Eukaryotic mRNA has a longer lifespan, enabling translational regulation.
• Protein synthesis elongation is energy-intensive and relies on eukaryotic elongation factors (eEFs).
• eEF2 facilitates GTP-dependent translocation of nascent protein chains on ribosomes.

Purpose of the Study:

• To elucidate the regulatory mechanisms of eEF2 kinase.
• To understand how cells control protein synthesis during nutrient deprivation.
• To explore the role of eEF2 in milk protein synthesis.

Main Methods:

• Investigated eEF2 regulation through phosphorylation/dephosphorylation by eEF2 kinase.
• Examined the calcium/calmodulin dependence of eEF2 kinase activity.
• Analyzed the influence of MAP kinase and mTOR signaling pathways on eEF2 kinase.

Main Results:

• eEF2 kinase activity is modulated by calcium, calmodulin, MAP kinase, and mTOR signaling.
• Cellular stimuli can inhibit or activate eEF2, controlling peptide chain elongation.
• eEF2 regulation conserves energy under nutrient-poor conditions.
• eEF2 appears to be a limiting factor in milk protein synthesis in lactating cows.

Conclusions:

• Regulation of eEF2 provides molecular insights into eukaryotic protein translocation.
• eEF2 is a key regulator of protein synthesis, particularly under stress conditions.
• Elongation factors like eEF2 are potential targets for synthetic biology applications, including milk protein production.