The ubiquitous pyridoxal 5'-phosphate-binding protein is also an RNA-binding protein

Area of Science:

• Biochemistry
• Molecular Biology
• Genetics

Background:

• Pyridoxal 5 '-phosphate binding protein (PLP-BP) is vital for PLP homeostasis across all kingdoms of life.
• Human PLP-BP variants are linked to neonatal epilepsy, yet its precise function remains unknown.
• Escherichia coli YggS is a well-studied PLP-BP homolog.

Purpose of the Study:

• To elucidate the function of PLP-BP in cellular metabolism.
• To investigate the interaction between YggS and RNA.
• To determine the role of PLP in modulating this interaction.

Main Methods:

• Investigated RNA binding by YggS.
• Analyzed the effect of PLP on RNA binding affinity.
• Utilized RNA-seq to identify co-purified RNAs.
• Examined evolutionary conservation of the RNA binding site.

Main Results:

• YggS directly binds RNA, and PLP modulates this interaction.
• Lys137 is crucial for RNA binding.
• The RNA binding site is conserved in human PLP-BP.
• SsrA and RnpB RNAs were identified as major binding partners.
• PLP likely influences RNA binding affinity by altering protein conformation.

Conclusions:

• PLP-BP's function may involve RNA interaction modulated by PLP.
• This interaction suggests a role in an uncharacterized regulatory mechanism.
• The findings open new avenues for understanding PLP-BP's role in cellular processes.