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Isolation of Translating Ribosomes Containing Peptidyl-tRNAs for Functional and Structural Analyses
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The race to decipher the top secrets of TOP mRNAs

Oded Meyuhas1, Tamar Kahan2

  • 1Department of Biochemistry and Molecular Biology, Institute for Medical Research - Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel.

Biochimica Et Biophysica Acta
|September 20, 2014
PubMed

Insights

Cells under stress, such as in tumors, reduce protein synthesis by repressing 5' Terminal OligoPyrimidine (5'TOP) mRNAs. Research focuses on identifying TOP mRNA family members and the regulators controlling this translational repression.

Area of Science:

  • Molecular Biology
  • Cellular Stress Response
  • Cancer Biology

Background:

  • Cells in harsh environments, like solid tumors, conserve energy by limiting protein synthesis.
  • This involves downregulating the translation of specific messenger RNAs (mRNAs).
  • A key mechanism utilizes the 5' Terminal OligoPyrimidine (5'TOP) motif present in these mRNAs, termed TOP mRNAs.

Purpose of the Study:

  • To review the current understanding of TOP mRNAs.
  • To highlight research progress in identifying TOP mRNA family members.
  • To discuss the pathways and factors regulating TOP mRNA translational repression during cellular stress.

Main Methods:

  • Literature review and critical analysis of existing research on TOP mRNAs.
  • Focus on studies investigating the scope of TOP mRNA family members.
  • Examination of research defining stress-induced translational control pathways and regulatory factors.

Main Results:

  • The research landscape of TOP mRNAs has expanded significantly.
  • Progress has been made in identifying the full range of TOP mRNA targets.
  • Understanding of the signaling pathways and proximal regulators governing TOP mRNA repression is advancing.

Conclusions:

  • TOP mRNAs represent a crucial mechanism for cellular resource conservation under stress.
  • Further research is needed to fully elucidate the complete set of TOP mRNAs and their precise regulatory mechanisms.
  • Understanding TOP mRNA regulation is vital for insights into cancer biology and therapeutic strategies.
Keywords:
4E-BPLARP1S6KTIA-1TOP mRNAsmiR-10a

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