Inherent protein structural flexibility at the RNA-binding interface of L30e

Area of Science:

• Molecular Biology
• Structural Biology
• Biochemistry

Background:

• Ribosomal protein L30 in Saccharomyces cerevisiae autoregulates its expression.
• This autoregulation involves binding to a purine-rich internal loop in its pre-mRNA and mRNA.

Purpose of the Study:

• To elucidate the structural basis of Saccharomyces cerevisiae ribosomal protein L30 autoregulation.
• To investigate the conformational changes in L30 and its RNA target upon binding.

Main Methods:

• Nuclear Magnetic Resonance (NMR) spectroscopy to study the L30-RNA complex.
• X-ray crystallography to determine the crystal structure of an MBP-L30 fusion protein.
• Structure prediction algorithms.

Main Results:

• NMR and crystal structures reveal that both L30 and the RNA loop become more ordered upon complex formation.
• The crystal structure identified two distinct conformations for the flexible RNA-binding region of L30.
• Structure prediction algorithms struggled to accurately model the flexible RNA-binding region, consistent with experimental findings.

Conclusions:

• The inherent conformational flexibility of the L30 RNA-binding region is crucial for its function.
• This flexibility may be a general characteristic of protein regions involved in intermolecular interactions.
• Structural insights provide a basis for understanding ribosomal protein autoregulation.