Cobra Three-Finger Toxins Interact with RNA and DNA: Nucleic Acids as Their Putative Biological Targets

Area of Science:

• Biochemistry
• Toxicology
• Molecular Biology

Background:

• Three-finger toxins (TFTs) are a large family of snake venom proteins.
• TFTs are known to interact with protein receptors (neurotoxins) and cell membranes (cytotoxins).
• No prior data existed on TFTs' interaction with nucleic acids.

Purpose of the Study:

• To investigate the potential interaction between TFTs and nucleic acids (RNA and DNA).
• To explore if nucleic acid interaction is a common property of TFTs.
• To determine if this interaction could mediate known biological effects of TFTs.

Main Methods:

• Spectrophotometry to detect changes in RNA optical density.
• Ion-paired High-Performance Liquid Chromatography (HPLC) to assess changes in RNA charge.
• Electrophoretic Mobility Shift Assay (EMSA) to detect shifts in RNA and DNA mobility.

Main Results:

• Spectrophotometry showed TFTs increase RNA optical density over time.
• Ion-paired HPLC revealed a decrease in RNA's negative charge upon interaction with neurotoxin II.
• EMSA demonstrated reduced electrophoretic mobility of both RNA and DNA with various TFTs.

Conclusions:

• TFTs interact with both RNA and DNA.
• Nucleic acid interaction may be a common characteristic of the TFT family.
• This interaction could be responsible for certain TFT biological activities, including cytotoxin-induced apoptosis.