Synthetic Pentatricopeptide Repeat Proteins: Building a Toolkit for Precise RNA Control

Area of Science:

• Molecular Biology
• RNA Biology
• Biotechnology

Background:

• Pentatricopeptide repeat (PPR) proteins naturally direct RNA editing (cytidine-to-uridine and uridine-to-cytidine) in plants via a specific recognition code.
• This code allows for the rational design of synthetic PPR (synPPR) proteins with programmable RNA-binding specificity and stability.

Purpose of the Study:

• To review the structural and mechanistic principles of PPR-mediated RNA editing.
• To highlight advances in the design and application of synthetic PPR proteins as RNA engineering tools.

Main Methods:

• Leveraging the amino acid-nucleotide recognition code of PPR proteins to design synthetic variants.
• Fusing synthetic PPR scaffolds to DYW deaminase domains to create active RNA editors.
• Utilizing these engineered enzymes across bacteria, plants, and human cells.

Main Results:

• Synthetic PPR proteins can be programmed for specific RNA binding and stability.
• Fusions with DYW domains create customizable enzymes for precise C-to-U or U-to-C base conversion.
• Applications include RNA stabilization, translational regulation, and targeted RNA editing.

Conclusions:

• Synthetic PPR proteins are versatile RNA engineering tools with broad applications in research, biotechnology, and medicine.
• Emerging therapeutic potential for RNA-mediated diseases is significant.
• Further refinements in specificity, efficiency, and modularity will enhance their utility in synthetic biology and RNA therapeutics.