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Horizontal Gel Electrophoresis for Enhanced Detection of Protein-RNA Complexes
Published on: July 28, 2017
The RNA-binding protein La contributes to cell proliferation and CCND1 expression.
G Sommer1, J Dittmann, J Kuehnert
1Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA.
Oncogene
|September 22, 2010
Summary
The La protein regulates cell proliferation by controlling cyclin D1 (CCND1) levels. La protein depletion halts proliferation, while its restoration reverses this effect, highlighting its role in cancer.
Area of Science:
- Molecular Biology
- Cell Biology
- Oncology
Background:
- The La protein is a crucial RNA-binding protein involved in RNA metabolism.
- Its precise role in cell proliferation and cancer, particularly in relation to cyclin D1, requires further elucidation.
Purpose of the Study:
- To investigate the role of the La protein in cell proliferation and cyclin D1 (CCND1) expression.
- To explore the association between La protein, CCND1, and their impact on cell growth.
- To examine La protein expression in cervical cancer tissues.
Main Methods:
- Small interfering RNA (siRNA)-mediated depletion of La protein in various cell lines.
- Exogenous La protein expression in depleted cells to assess rescue effects.
- Analysis of CCND1 protein levels and cell proliferation rates.
- Reversible in vivo crosslinking and ribonucleoprotein (RNP) immunoprecipitation to study RNA-protein interactions.
- Western blot analysis of cervical cancer tissue lysates.
Main Results:
- La protein depletion significantly reduced cell proliferation and CCND1 protein levels.
- Exogenous La expression restored proliferation and CCND1 levels in depleted cells.
- La depletion did not affect the proliferation of CCND1 knockout cells, confirming functional coherence.
- Direct association between La protein and CCND1 mRNA was demonstrated.
- La protein levels were found to modulate CCND1 internal ribosome entry site (IRES)-dependent translation.
- Elevated La protein expression was observed in cervical cancer tissues, correlating with aberrant CCND1 levels.
Conclusions:
- The La protein plays a significant role in regulating cell proliferation, partly through its control over CCND1 expression.
- La protein directly interacts with CCND1 mRNA, influencing its translation.
- Overexpression of the La protein is a novel finding in solid tumors, specifically cervical cancer, suggesting its potential as a biomarker or therapeutic target.
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