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SnoRNA U50 levels are regulated by cell proliferation and rRNA transcription

Annalisa Pacilli1, Claudio Ceccarelli, Davide Treré

  • 1Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Sant'Orsola-Malpighi University Hospital, Bologna 40138, Italy. annalisa.pacilli@gmail.com

International Journal of Molecular Sciences
|July 23, 2013
PubMed

Insights

Small nucleolar RNA U50 (U50) downregulation in colon cancer correlates with reduced ribosomal RNA methylation and impaired ribosome function. This suggests U50’s role in regulating cell proliferation and its potential as a tumor suppressor.

Area of Science:

  • Molecular Biology
  • Cancer Research
  • RNA Biology

Background:

  • Post-transcriptional modifications of ribosomal RNA (rRNA) are crucial for ribosomal function and implicated in cancer development.
  • Small nucleolar RNA U50 (U50) targets C2848 methylation in 28S rRNA and has been proposed as a tumor suppressor in various cancers.

Purpose of the Study:

  • To investigate the role of U50 in colon cancer and its impact on cellular proliferation and ribosome function.
  • To explore the mechanisms underlying U50 downregulation in cancer.

Main Methods:

  • Analysis of U50 levels in colon cancer cell lines and tumors.
  • Investigating U50 expression and C2848 methylation in phytohemagglutinin-stimulated lymphocytes.
  • Assessing U50 stability and consumption under conditions of blocked ribosome biogenesis.
  • Evaluating the effect of U50 modulation on IRES-mediated translation.

Main Results:

  • U50 was found to be downregulated in colon cancer cell lines and tumors.
  • Decreased U50 levels in lymphocytes correlated with reduced C2848 methylation and were linked to altered U50 stability and increased consumption.
  • Blockade of ribosome biogenesis led to an initial decrease in U50, followed by stabilization.
  • U50 modulation was shown to affect ribosome efficiency in IRES-mediated translation.

Conclusions:

  • The study links U50 to cellular proliferation rates and ribosome biogenesis.
  • Findings suggest that reduced U50 levels contribute to altered ribosome function and may explain its downregulation in cancers.
  • U50's role in regulating ribosome efficiency highlights its potential significance in cancer development.

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