Palaeogenomics reveal a hybrid origin of the world's largest Camelus species

The extinct Camelus knoblochi is known as the largest camel in genus Camelus, but its relationship to modern Camelus species remains unclear. In this study, we reported the first mitochondrial and nuclear analyses of seven Late Pleistocene C. knoblochi samples from Northeastern China. We found that they are inseparable to wild Bactrian camel on the matrilineal side, but belong to a distinct cluster on the biparental nuclear side. Further admixture proportion analyses suggested hybrid ancestry between both the ancestors of the modern wild and domesticated Bactrian camels, with ~65% contribution from the former and ~35% from the later. By calculating the coalescence time for three Camelus species above, we estimated the hybridization event occurred between approximately 0.8 and 0.33 Ma. We also used Bayesian skyline to reconstruct the maternal demographic trajectories for different Camelus to better compare their evolutionary histories. Our results provide molecular insights into C. knoblochi and fill in a vital piece in understanding the genus Camelus.

Expression of the NSE, SP, NFH and DβH in Normal and Cryptorchid Testes of Bactrian Camel

Background: Neuroendocrine substances play important roles in regulating the normal physiological functions of testicles.The purpose of this study is to explore the localization and effects of four neuroendocrine markers(NSE, SP, NFH and DβH) in normal and cryptorchid testes of Bactrian camels.Methods: The cryptorchid testes were located in the abdominal cavity and were collected by orchiectomy. Fresh testes tissues were processed into small pieces and then divided into three samples. One sample was frozen in liquid nitrogen for western blotting hybridization reaction, while the other sample was fixed with 4% paraformaldehyde solution for histochemical analysis, and the third fixed in glutaraldehyde for transmission electron microscopy observation.Results: The results showed that cryptorchidism caused a reduction in layers of spermatogenic epithelium and decreased glycogen positivity in the basement membrane.The ultrastructure revealed that macrophages were always found around the Leydig cells, which were crowded with swelling mitochondria in cryptorchidism. Expression of NSE in the Leydig cells of cryptorchidism was significantly weakened compared to that in the normal group(p<0.01). We found that SP was always distributed along the nerve fibers in normal testes and was expressed in the Leydig cells of cryptorchidism. However, expression of NFH in the cryptorchidic tissue was strongly positive in spermatogenic epithelium, with limited expression in Leydig cells and no expression in peritubular myoid cells. Therefore, expression of DβH in the Sertoli cells was comparatively strong in both the normal and cryptorchidism groups.NFH and DβH expression was significantly increased in the cryptorchidism group compared with the nomal group(p<0.01).Conclusions: These findings indicated that the underdeveloped seminiferous epithelium and pathological changes in cryptorchid tissue in Bactrian camels were potentially related to a disorder in glycoprotein metabolism.Our results suggest that NSE and SP could helpful to judge the pathological changes of cryptorchidism. The present study provides the first evidence at the protein level for the existence of NFH and DβH in Sertoli and Leydig cells in Bactrian camel cryptorchidism and provides a more in-depth understanding of neuroendocrine regulation is crucial for animal cryptorchidism.

Generation of a Bactrian camel hepatitis E virus by a reverse genetics system

Bactrian camel hepatitis E virus (HEV) is a novel HEV belonging to genotype 8 (HEV-8) in the Orthohepevirus A species of the genus Hepevirus in the family Hepeviridae. HEV-8 cross-transmits to cynomolgus monkeys and has a potential risk for zoonotic infection. Until now, neither a cell-culture system to grow the virus nor a reverse genetics system to generate the virus has been developed. To generate replication-competent HEV-8 and to establish a cell-culture system, we synthesized capped genomic HEV-8 RNAs by in vitro transcription and used them to transfect into PLC/PRF/5 cells. A HEV-8 strain, HEV-8M2, was recovered from the capped HEV-8 RNA–transfected cell-culture supernatants and subsequently passaged in the cells, demonstrating that PLC/PRF/5 cells were capable of supporting the replication of the HEV-8, and that a cell-culture system for HEV-8 was successfully established. In addition to PLC/PRF/5 cells, A549 and Caco-2 cells appeared to be competent for the replication, but HepG2 C3/A, Vero, Hela S3, HEp-2C, 293T and GL37 cells were incompetent. The HEV-8M2 strain was capable of infecting cynomolgus monkeys by an intravenous inoculation, indicating that HEV-8 was infectious and again carried a risk for zoonotic infection. In contrast, HEV-8 did not infect nude rats and BALB/c nude mice, suggesting that the reservoir of HEV-8 was limited. In addition, the replication of the HEV-8M2 strain was efficiently abrogated by ribavirin but not by favipiravir, suggesting that ribavirin is a drug candidate for therapeutic treatment of HEV-8-induced hepatitis. The infectious HEV-8 produced by a reverse genetics system would be useful to elucidate the mechanisms of HEV replication and the pathogenesis of type E hepatitis.

On the dynastic cult of the rulers of Bukhara Sogd in the Early Middle Ages (to the interpretation of the murals of the Varakhsha palace)

Varakhsha hillfort is located in the Bukhara oasis (Uzbekistan). From the 6th to 8th c., it was the residence of the rulers of Bukhara Sogd. Archaeological investigations of the Varakhsha were carried out in the late 1930s, and then later in 1947 and 1949–1954. During the excavations of the palace, wall paintings were discovered in the Red (Hindu) and East (Blue) Halls (7th–8th c.). In the East Hall, the center of the art composition on the south wall was dominated by a massive figure of a ‘king’ with a golden sword, seated on a throne with protomas of winged camels. Depicted next to him was a group of five people sitting on their knees — the king's family. The elder man is making an offering to the fire on an altar. On the base of the altar, there is a male figure, seated on a throne in the form of a lying camel. This figure represents Vretragna, the Avestan deity of Victory. Mythogenically, Vretragna is close to the Vedic god of thunder Indra. In Avesta, Vretragna appears in various guises: a Bactrian camel; the bird of prey Varagn; a man with a golden sword. In Sogdian iconography, the image of the Bactrian camel is most often associated with Vretragna. The characters of the murals in the Blue Hall (the king’s family) bring offering to the fire lit in tribute to the deity — to Vretragna. The central figure of this composition was identi-fied by V.A. Shishkin as a king. In our opinion, it rather depicts Vretragna. This is implicitly indicated by the protomas of the throne in the form of winged camels and by the image of ‘the king with the golden sword’. The walls of the Red Hall of Varakhsha were decorated with a scene of hunters riding elephants. Each elephant was ridden by a servant-mahout and a lord, whose figure would be disproportionately large. They are slaying huge monsters. According to researchers, an image of the Sogdian deity Adbag is repeated here. The epithet ‘Adbag’ — ‘Supreme deity’ is associated with Ahuramazda. B.I. Marshak and A.M. Belenitsky note, that here Adbag-Ahuramazda is likened to Indra riding a white elephant. It seems to us quite probable that such an epithet could be applied to various gods of a high status. Notably, it could be Vretragna depicted here, who is akin to Indra. We think that the image of Vretragna held a special place in the visual arts of Varakhsha, as the patron deity of the Bukhar-Khudat dynasty. He was depicted in the center of the com-position in the Blue Hall in his Avestan hypostasis, and in the Red Hall he was depicted in the form of Indra.

The Affects of Genital Myiasis on the Diversity of Vaginal Flora in Female Bactrian Camels

Background: One of the most important diseases that affect the reproductive organs of Bactrian camels is called Genital Myiasis. It can cause serious mechanical damage to the vaginal tissue of female Bactrian camels. The accumulation of bacteria in the vagina of female camels can affect their health and reproductive ability. The effect of this damage is commonly found in the vaginal flora and vaginal mucosal immune system. Therefore, this research is a study of the diversity of the vaginal flora and the differences between healthy Bactrian camels and those suffering from Genital Myiasis.Results: Vaginal microbiota samples were collected from two groups of female Bactrian camels of the same age. Illumina Miseq was used to sequence V3-V4 hypervariable genes of 16S rRNA in the samples, and the results showed that the vaginal microflora of the infected camel had a significantly greater OTU value. According to the Alpha diversity index and the level of vaginal pH, the diversity index of the infected camel flora were higher than that of the normal camel flora, and the pH were lower than that of the normal camel flora (P=0.006). There was no significant difference between the two groups in the abundance of dominant genera of Bactrian camel vaginal (P＞0.05), indicating that the structure of dominant flora of Bactrian camel vagina had a certain stability.Conclusions: Overall this comparison revealed the differences and similarities between vaginal flora Bactrian camels in various health states. In addition, this data provides a reference point for understanding the types of bacteria that cause genital myiasis that damages healthy development of Bactrian camels.

Exploring the genomic resources of seven domestic Bactrian camel populations in China through restriction site-associated DNA sequencing

The domestic Bactrian camel is a valuable livestock resource in arid desert areas. Therefore, it is essential to understand the roles of important genes responsible for its characteristics. We used restriction site-associated DNA sequencing (RAD-seq) to detect single nucleotide polymorphism (SNP) markers in seven domestic Bactrian camel populations. In total, 482,786 SNPs were genotyped. The pool of all remaining others were selected as the reference population, and the Nanjiang, Sunite, Alashan, Dongjiang, Beijiang, Qinghai, and Hexi camels were the target populations for selection signature analysis. We obtained 603, 494, 622, 624, 444, 588, and 762 selected genes, respectively, from members of the seven target populations. Gene Ontology classifications and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed, and the functions of these genes were further studied using Genecards to identify genes potentially related to the unique characteristics of the camel population, such as heat resistance and stress resistance. Across all populations, cellular process, single-organism process, and metabolic process were the most abundant biological process subcategories, whereas cell, cell part, and organelle were the most abundant cellular component subcategories. Binding and catalytic activity represented the main molecular functions. The selected genes in Alashan camels were mainly enriched in ubiquitin mediated proteolysis pathways, the selected genes in Beijiang camels were mainly enriched in MAPK signaling pathways, the selected genes in Dongjiang camels were mainly enriched in RNA transport pathways, the selected genes in Hexi camels were mainly enriched in endocytosis pathways, the selected genes in Nanjiang camels were mainly enriched in insulin signaling pathways, while the selected genes in Qinghai camels were mainly enriched in focal adhesion pathways; these selected genes in Sunite camels were mainly enriched in ribosome pathways. We also found that Nanjiang (HSPA4L and INTU), and Alashan camels (INO80E) harbored genes related to the environment and characteristics. These findings provide useful insights into the genes related to the unique characteristics of domestic Bactrian camels in China, and a basis for genomic resource development in this species.