Impact of the CYP27B1 p.R389H mutation on protein stability and function: implications for multiple sclerosis...

Area of Science:

• Genetics and Molecular Biology
• Biochemistry
• Computational Biology

Background:

• The CYP27B1 gene is vital for vitamin D metabolism, influencing immune system regulation.
• Genetic variations in CYP27B1, such as the p.R389H mutation (rs118204009), are investigated for their potential impact on health, including links to multiple sclerosis (MS).

Purpose of the Study:

• To computationally assess the structural and functional consequences of the CYP27B1 p.R389H mutation.
• To evaluate the potential role of this mutation in the pathogenesis of multiple sclerosis.

Main Methods:

• 3D protein structure prediction using AlphaFold and PyMOL.
• Structural validation via ERRAT2, VERIFY3D, and Ramachandran analysis.
• Stability prediction using I-Mutant, Mcsm, DDGun, DynaMut, and Mupro.
• Functional impact assessment using PolyPhen-2, PhD-SNP, SNPs&GO, and SIFT.
• Evolutionary conservation analysis with ConSurf.
• Molecular dynamics simulations.

Main Results:

• AlphaFold generated a high-confidence CYP27B1 structure, localizing the p.R389H mutation (Arginine to Histidine substitution) in a conserved region.
• Stability analyses predicted a destabilizing effect of the mutation (ΔΔG: -0.3 to -2.038 kcal/mol).
• Functional prediction tools classified p.R389H as 'probably damaging' and disease-associated, supported by molecular dynamics simulations showing reduced protein stability and flexibility.

Conclusions:

• The p.R389H mutation in CYP27B1 is predicted to be destabilizing and functionally damaging.
• This mutation may impair vitamin D metabolism, suggesting a potential role in the pathogenesis of multiple sclerosis.