Regulation of ribozyme activity by engineered protein switch

Area of Science:

• Biochemistry
• Molecular Biology
• RNA catalysis

Background:

• The ribonuclease P (RNase P) ribozyme is a crucial enzyme in RNA processing.
• The P3 domain of RNase P is known to be important for its catalytic activity.
• Previous studies demonstrated the possibility of in vitro truncation and replacement of the P3 domain.

Purpose of the Study:

• To engineer the P3 domain of the Escherichia coli ribonuclease P ribozyme.
• To investigate the functional consequences of replacing the P3 domain with a heterologous sequence (HIV TAR).
• To assess the interaction of the engineered ribozyme with HIV tat protein.

Main Methods:

• Construction of a P3-replaced variant of the E. coli ribonuclease P ribozyme using the HIV TAR sequence.
• Assay of ribonuclease P activity of the engineered ribozyme.
• Evaluation of the inhibition of the engineered ribozyme by an HIV tat protein fragment.

Main Results:

• The P3-replaced ribozyme exhibited significant ribonuclease P activity.
• The engineered ribozyme's activity was inhibited by the presence of the HIV tat protein fragment.
• This demonstrates successful engineering of the P3 domain and potential for heterologous protein subunit interaction.

Conclusions:

• The P3 domain of E. coli ribonuclease P ribozyme is amenable to engineering.
• Replacing the P3 domain with heterologous sequences like HIV TAR is feasible.
• The engineered P3 domain can interact with specific protein subunits, such as HIV tat protein, influencing ribozyme activity.