Binase cleaves cellular noncoding RNAs and affects coding mRNAs

Area of Science:

• Biochemistry
• Molecular Biology
• Cancer Research

Background:

• Bacterial RNases show potential as anticancer agents by targeting RNA accumulation in neoplastic cells.
• Cancer cells exhibit altered RNA expression, including rRNA, tRNA, and regulatory noncoding RNAs.
• Exogenic RNases induce cytotoxicity in cancer cells primarily through RNA cleavage.

Purpose of the Study:

• To investigate the effects of binase, a cytotoxic ribonuclease from Bacillus intermedius, on intracellular RNA levels and gene expression in cancer cells.
• To determine the correlation between binase-induced RNA reduction, cell viability, and apoptosis.
• To explore binase's role in regulating RNA-dependent processes of cell proliferation and apoptosis.

Main Methods:

• Utilized fluorescence microscopy to visualize cellular RNA in four cell lines.
• Employed flow cytometry to quantify RNA levels, cell viability, and apoptosis.
• Conducted quantitative RT-PCR to analyze mRNA expression of key apoptotic and antiapoptotic genes.

Main Results:

• Binase treatment significantly decreased intracellular RNA levels in sensitive cell lines (e.g., 44% in HEKhSK4 cells).
• The most substantial RNA decrease was observed in apoptotic cell subpopulations, though not directly correlated with apoptosis.
• Binase altered the expression of apoptosis-related genes, reducing bcl-2 mRNA and increasing p53 and hSK4 mRNA.

Conclusions:

• Binase effectively reduces intracellular RNA levels and modulates the expression of proapoptotic and antiapoptotic genes.
• Binase's impact on RNA levels and gene expression suggests its potential as a regulator of cancer cell proliferation and apoptosis.
• The study highlights binase as a promising candidate for developing novel RNA-targeting anticancer therapies.