RNA editing-associated protein 1 is an RNA binding protein with specificity for preedited mRNA

Area of Science:

• Molecular Biology
• Genetics
• Biochemistry

Background:

• Kinetoplastid mitochondrial RNA editing involves uridine addition/deletion guided by guide RNAs (gRNAs).
• Ribonucleoprotein (RNP) complexes are known to perform this posttranscriptional RNA processing.
• REAP-1, a protein primarily found in mRNA editing complexes, has an uncharacterized function.

Purpose of the Study:

• To characterize the function of REAP-1 within RNA editing complexes.
• To determine the RNA binding properties of REAP-1.
• To elucidate the role of REAP-1 in the RNA editing process.

Main Methods:

• RNA binding assays were performed to assess REAP-1's interaction with various RNA substrates.
• The specific RNA binding domain within REAP-1 was mapped.
• Binding preferences of REAP-1 for different RNA types, including preedited RNAs, were analyzed.

Main Results:

• REAP-1 was identified as an RNA binding protein.
• RNA binding activity was localized to the amino-terminal third of REAP-1.
• REAP-1 exhibits binding to poly(G) and guanosine-rich single-stranded RNAs.
• Preedited mRNAs were found to be the preferred substrate for REAP-1 binding.

Conclusions:

• REAP-1 plays a crucial role in the RNA editing machinery of kinetoplastids.
• The findings suggest REAP-1 functions by binding to preedited mRNAs.
• This binding activity likely facilitates the recruitment of preedited mRNAs into the editing complex.