The First Report of Genetic Characteristics and Polymorphisms in the Shadow of Prion Protein Gene (SPRN) in Bats

The shadow of prion protein (Sho), encoded by the shadow of prion protein gene (SPRN), is a prion-like protein that shares structural and cellular localization similarities with the prion protein (PrP).Emerging evidence suggests that Sho may act as a modulator of PrP misfolding.However, prion diseases have not been reported in bats, and the role of SPRN genetic variation in this potential resistance remains unexplored.Genomic DNA was extracted from 100 bat samples, and the SPRN gene was amplified and sequenced to identify variations.Genetic analysis, including genotype, allele, haplotype frequencies, and linkage disequilibrium (LD), was performed to characterize the bat SPRN gene.Comparative protein sequence alignment across several species was conducted to assess evolutionary conservation.The structural properties of bat Sho and the impact of non-synonymous substitutions on bat Sho were evaluated using structural modeling tools.The functional effects of identified variants were predicted using multiple in-silico approaches.A total of 20 polymorphisms were identified in the coding region of the bat SPRN gene, including 11 non-synonymous variants.Notably, the bat SPRN gene displayed a distinct polymorphism pattern compared to both prion-susceptible species and putatively prion-resistant species.Comparative analysis demonstrated that bat Sho shares high sequence similarity with other mammalian Sho.Computational analyses predicted that certain low-frequency variants, including W9R, G68E, and G76E, may influence protein stability and Sho-PrP interactions.This study represents the first report describing SPRN gene polymorphisms in bats, offering baseline insights for future studies on prion biology.