Structural Assembly of Mink Enteritis Virus and Its Evolutionary Relationship Among Mammalian Parvoviruses

Mink enteritis virus (MEV), a member of Protoparvovirus genus within the Parvovirinae , induces severe hemorrhagic enteritis and leukopenia in minks, posing a substantial economic threat to mink farming. MEV, feline panleukopenia virus (FPV) and canine parvovirus (CPV) are closely related Protoparvovirus members, with CPV and FPV infecting hosts by binding to transferrin receptor 1 (TfR1). However, the structural mechanism underlying MEV entry remains poorly understood. This study employs cryo-electron microscopy (cryo-EM) and structural bioinformatics to investigate MEV through determining the structure of MEV virus-like particles (VLPs) at 2.5 Å in resolution. The analysis reveals that MEV shares a highly conserved capsid structure with CPV and FPV, particularly in the β-barrel core and three-fold protrusions. Notably, MEV utilizes the mink TfR1 for host entry, similar to CPV and FPV. Structural superposition and sequence alignment identify key residues in MEV VP2 protein critical for mink TfR1 interaction. This research provides structural and evolutionary insights into MEV’s host tropism, offering valuable information for mitigating zoonotic risks of mammalian parvoviruses.