Structural basis of glycoform selectivity in prion strains

Area of Science:

• Neuroscience
• Structural Biology
• Biochemistry

Background:

• Prion diseases involve misfolding of cellular prion protein (PrPC) into neurotoxic PrPSc aggregates.
• Prion strains, distinct PrPSc conformations, cause varied disease phenotypes and transmission.
• Glycosylation, especially sialylation, influences PrPSc replication and prion disease propagation.

Purpose of the Study:

• To elucidate the molecular basis of glycoform preferences in distinct prion strains (RML and ME7).
• To understand how glycosylation impacts prion strain characteristics and disease phenotypes.

Main Methods:

• Utilized high-resolution cryo-electron microscopy (cryo-EM) structural data.
• Performed all-atom molecular dynamics simulations.
• Analyzed glycoform preferences in RML and ME7 mouse prion strains.

Main Results:

• Identified differential engagement of the major basic patch and palindromic region of PrP as key determinants of glycoform preference.
• Demonstrated that these interactions explain the distinct glycoform preferences observed in RML and ME7 strains.
• Provided molecular insights into how glycosylation influences prion strain behavior.

Conclusions:

• Glycoform preferences are fundamentally determined by specific interactions between prion strains and the PrP structure.
• This finding illuminates a crucial, previously poorly understood aspect of prion biology and disease mechanisms.
• Understanding these molecular interactions may offer new avenues for therapeutic strategies against prion diseases.