Nucleotide structure of prion protein gene in Egyptian camels

Abstract

The prion protein is coded by the PRP gene which is active in the brain and several other tissues. The functions of normal PrPs are related to energy production, protein degradation and DNA replication. Prions are the essential factor for the transmissible spongiform encephalopathies (TSEs) in different mammalian species. The present study aimed to identify the nucleotide characterization of the PRP gene in six camel breeds reared in Egypt. Genomic DNA which was extracted from 80 camels belonging to six breeds reared in Egypt was used to amplify fragments at 725-bp using a specific primer for PRP gene. Alignment of Egyptian camel PRP nucleotide sequences with those of other mammalian species declared the similarity 100% between PRP sequences of Egyptian and Iranian camels and 99.7% similarity with English, German and Chinese camel populations. The nucleotide sequence of Egyptian camel was submitted to GenBank under the accession no.: MF685344. The comparison between PRP amino acids of Camelus species with other mammalian species showed two missing amino acids in Camelus and Lama glama species; Glycine at position 83 and Leucine at position 229 whereas there is a unique amino acid addition-Glycine at position 89in Camelus species.

Genetic characterization of the prion protein gene in camels (Camelus) with comments on the evolutionary history of prion disease in Cetartiodactyla

“…All 50 individuals representing eight breeds of Ethiopian C. dromedarius were monomorphic for the PRNP gene and were 100% identical to the nucleotide sequences reported for the CPD–positive individuals in Algeria ( Babelhadj et al, 2018 ). Most studies ( Abdel-Aziem et al, 2019 ; Adeola et al, 2024 ; Babelhadj et al, 2018 ; Kaluz, Kaluzova & Flint, 1997 ; Tahmoorespur & Jelokhani Niaraki, 2014 ; Tahmoorespur & Jelokhani Niaraki, 2014 ; Xu et al, 2012 ; Zoubeyda et al, 2020 ) report low variability in the PRNP gene among Camelus (0.42% reported herein). Three synonymous nucleotide substitutions (T231C, T243A, and T264C), identified as phylogenetically informative by Parsimony analyses, differentiated the two Camelus species.…”

“…Previous genetic studies of dromedary camels in Algeria, Egypt, and Ethiopia ( Cherifi et al, 2017 ; Legesse et al, 2018 ) reported a lack of morphological, genetic variation, and population structure indicating homogeneity in the nuclear genome of C. dromedarius . In addition, low variability of camel PRNP sequences has been reported compared to other sequences representative of dromedary camels ( Abdel-Aziem et al, 2019 ; Babelhadj et al, 2018 ; Kaluz, Kaluzova & Flint, 1997 ; Tahmoorespur & Jelokhani Niaraki, 2014 ; Xu et al, 2012 ; Zoubeyda et al, 2020 ). Given the broad distribution of camel breeds across northern Africa and the apparent lack of genetic variation among breeds, it is hypothesized that Ethiopian dromedary camels will have similar PRNP genotypes to other dromedary camels.…”

Single nucleotide polymorphisms (SNPs) in the open reading frame (ORF) of prion protein gene (PRNP) in Nigerian livestock species

“…Contrarily, previous studies on polymorphism of PRNP gene in Nigerian small ruminants, 29 SNPs (14 non-synonymous and 23 novel SNPs) and 19 SNPs (14 non-synonymous SNPs with T718C as a novel SNP) were revealed in Nigerian goats and sheep, respectively [ 30 , 34 ]. Recent studies have reported low variation in dromedary PRNP gene in Egypt and Iran [ 53 , 54 ]. Two non-synonymous SNPs (G205A and G401A) were identified in PRNP gene in Algerian dromedary [ 55 ] but not detected in the present study for Nigerian camel.…”