Quantitative analyses of interactions between SpoVG and RNA/DNA.

Area of Science:

• Microbiology
• Molecular Biology
• Biochemistry

Background:

• The Borrelia burgdorferi SpoVG protein is known to bind both DNA and RNA.
• Understanding the specific interactions of SpoVG with nucleic acids is crucial for elucidating its function.

Purpose of the Study:

• To determine the binding affinities of the SpoVG protein to various RNA and DNA sequences.
• To identify potential ligand motifs and structural determinants of SpoVG-nucleic acid interactions.

Main Methods:

• Binding and competition assays were performed using various RNA and single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA) targets.
• Specific loci including spoVG, glpFKD, erpAB, bb0242, flaB, and ospAB were analyzed, with a focus on 5' untranslated regions of mRNAs.
• Mutagenesis studies were conducted on SpoVG RNA and ssDNA sequences.

Main Results:

• The 5' end of spoVG mRNA exhibited the highest binding affinity for the SpoVG protein.
• The 5' end of flaB mRNA showed the lowest binding affinity.
• SpoVG-nucleic acid complex formation was not solely dependent on specific sequences or structures.
• Substitution of uracil with thymine in ssDNAs did not alter protein-nucleic acid complex formation.

Conclusions:

• The SpoVG protein displays differential binding affinities towards various nucleic acid targets, with a preference for its own mRNA's 5' end.
• Nucleic acid binding by SpoVG is influenced by factors beyond mere sequence or secondary structure.
• These findings contribute to understanding the regulatory roles of SpoVG in Borrelia burgdorferi.