Excessive replacement changes drive evolution of global sheep prion protein (PRNP) sequences
Küçük Resim Yok
Tarih
2022
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Springernature
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Sheep prion protein (PRNP) is the major host genetic factor responsible for susceptibility to scrapie. We aimed to understand the evolutionary history of sheep PRNP, and primarily focused on breeds from Turkey and Ethiopia, representing genome-wise ancient sheep populations. Population molecular genetic analyses are extended to European, South Asian, and East Asian populations, and for the first time to scrapie associated haplotypes. 1178 PRNP coding region nucleotide sequences were analyzed. High levels of nucleotide diversity driven by extensive low-frequency replacement changes are observed in all populations. Interspecific analyses were conducted using mouflon and domestic goat as outgroup species. Despite an abundance of silent and replacement changes, lack of silent or replacement fixations was observed. All scrapie-associated haplotype analyses from all populations also showed extensive low-frequency replacement changes. Neutrality tests did not indicate positive (directional), balancing or strong negative selection or population contraction for any of the haplotypes in any population. A simple negative selection history driven by prion disease susceptibility is not supported by the population and haplotype based analyses. Molecular function, biological process enrichment, and protein-protein interaction analyses suggested functioning of PRNP protein in multiple pathways, and possible other functional constraint selections. In conclusion, a complex selection history favoring excessive replacement changes together with weak purifying selection possibly driven by frequency-dependent selection is driving PRNP sequence evolution. Our results is not unique only to the Turkish and Ethiopian samples, but can be generalized to global sheep populations.
Açıklama
Anahtar Kelimeler
Gene Prnp, Haplotype Reconstruction, Statistical Properties, Molecular Evolution, Scrapie, Neutrality, Resistance, Bovine, Tests, Mice
Kaynak
Heredity
WoS Q Değeri
Q2
Scopus Q Değeri
Q2
Cilt
128
Sayı
5
