eEF1Bγ binds the Che-1 and TP53 gene promoters and their transcripts

Area of Science:

• Molecular Biology
• Cell Biology
• Genetics

Background:

• The eukaryotic elongation factor subunit 1B gamma (eEF1Bγ) interacts with RNA polymerase II (pol II) and binds vimentin gene promoter and mRNA.
• These interactions are crucial for vimentin transcript localization, translation, and proper mitochondrial network formation.

Purpose of the Study:

• To identify additional transcripts that complex with the eEF1Bγ protein.
• To investigate the role of eEF1Bγ in cellular stress responses and its interaction with key regulatory transcripts.

Main Methods:

• Ribonucleoprotein immunoprecipitation (RIP) assays were performed on a mitochondria-enriched heavy membrane (HM) fraction.
• Doxorubicin (Dox)-induced DNA damage assays were conducted to assess protein accumulation upon eEF1Bγ depletion.

Main Results:

• eEF1Bγ was found to complex with mRNA encoding Che-1/AATF and the tumor suppressor p53.
• eEF1Bγ binds to the transcripts and promoters of Che-1 and p53.
• Depletion of eEF1Bγ disrupts mitochondrial network and Che-1 localization, and impairs p53 accumulation during DNA damage.

Conclusions:

• eEF1Bγ functions as an RNA-binding protein involved in cellular stress responses beyond its canonical role in translation.
• eEF1Bγ acts as a link between transcription control and local translation, suggesting a role as a primordial transcription/translation factor.