Eef2

Definition

Eukaryotic elongation factor 2 (eef2) is a protein that plays a critical role in the elongation phase of protein synthesis within eukaryotic cells. It facilitates the translocation of the ribosome along the mRNA strand during translation, ensuring that amino acids are added in the correct sequence to form proteins. This factor is essential for proper protein synthesis and cellular function, as it helps maintain the speed and accuracy of translation.

5 Must Know Facts For Your Next Test

1. Eef2 binds to the ribosome and is essential for moving the ribosome along the mRNA during translation.
2. It works in conjunction with eef1, another elongation factor, which brings aminoacyl-tRNA to the ribosome for incorporation into the growing polypeptide chain.
3. Eef2 is regulated by phosphorylation, specifically by a kinase known as eEF2K, which can inhibit its activity under stress conditions.
4. The function of eef2 is vital for maintaining proper translation rates, as any dysfunction can lead to errors in protein synthesis and potentially harmful cellular consequences.
5. Certain toxins, like diphtheria toxin, can modify eef2, leading to inhibition of protein synthesis and ultimately causing cell death.

Review Questions

• How does eef2 contribute to the process of translation within eukaryotic cells?
  • Eef2 plays a crucial role during the elongation phase of translation by facilitating the movement of the ribosome along the mRNA strand. This translocation allows for the proper positioning of tRNAs, ensuring that amino acids are added in the correct order to form proteins. Without eef2, ribosomes would stall on mRNA, disrupting protein synthesis and impacting overall cell function.
• Discuss the significance of eef2 regulation through phosphorylation and its implications for cellular stress responses.
  • Eef2 is regulated by phosphorylation through eEF2K, which inhibits its function under stress conditions. This regulation is significant because it helps the cell conserve resources when under duress, slowing down protein synthesis to prioritize survival. Understanding how this mechanism works can provide insights into how cells adapt to stress and how dysregulation might lead to diseases like cancer.
• Evaluate how modifications of eef2 by toxins such as diphtheria toxin affect protein synthesis and overall cellular health.
  • Modifications of eef2 by toxins like diphtheria toxin can lead to severe consequences for protein synthesis. The toxin ADP-ribosylates eef2, effectively inhibiting its ability to facilitate ribosomal translocation. This results in halted protein production, which can lead to cell death. Evaluating these effects highlights the importance of eef2 in maintaining cellular health and underscores potential therapeutic targets for diseases associated with impaired translation.

Related terms

Ribosome: A molecular machine composed of ribosomal RNA and proteins that assembles amino acids into proteins based on the sequence of mRNA.

Translation: The process by which ribosomes synthesize proteins by translating the information encoded in messenger RNA (mRNA) into a specific amino acid sequence.

GTPase: An enzyme that hydrolyzes guanosine triphosphate (GTP) to guanosine diphosphate (GDP), playing a role in signal transduction and energy transfer in cellular processes.