A novel sheep gene, MMP7, differentially expressed in muscles from black-boned sheep and local common sheep

An ethnobiological study on traditional knowledge associated with black-boned sheep (Ovis aries) in Northwest Yunnan, China

BACKGROUND

Black-boned sheep is a precious genetic resource with black quality traits cultivated by the Pumi people in Tongdian Town, Lanping County, Nujiang Lisu Autonomous Prefecture, Northwest Yunnan, China. It has been included in the "National Breed List of Livestock and Poultry Genetic Resources." The local communities have a deep understanding of black-boned sheep. The traditional knowledge of black-boned sheep is essential to their conservation and sustainable development. In spite of this, there was no information on traditional knowledge associated with black-boned sheep so far. The aim of this study wasaimed to document traditional knowledge and culture, to elucidate information about forage plants, and to investigate the conservation strategy of black-boned sheep.

METHOD

Four field surveys were conducted from July 2019 to May 2021. A total of seven villages and the Pumi Culture Museum in Lanping County are being investigated. A semi-structured interview method was used to interview 67 key informants. During the investigation, we also participated in the grazing activities of black-boned sheep, observed the appearance characteristics and the herd structure of the black-boned sheep, and demonstrated traditional knowledge regarding black-boned sheep, including grazing methods, forage plants, and related customs and habits.

RESULTS

We assumed that a majority of people in the current study sites were able to could distinguish black-boned sheep from their relatives by their black bones, blue-green gums, and blue-purple anus. The local people manage their black-boned sheep based on the number of sheep by sex, age, and role in a flock in the different breeding environments. Different grazing strategies have been adopted in different seasons. Through ethnobotanical investigations, 91 species of forage plants in 30 families were identified, including herbaceous, shrubs, lianas, and trees. Among all the plant species consumed by the black-boned sheep, Rosaceae species make up the greatest number, with 16, followed by Asteraceae, with 9, and 8 species of Fabaceae and Poaceae. Considering the abundance of forage plants and the preference for black-boned sheep, Prinsepia utilis and the plants of Rubus, Berberis, and Yushania occupy dominant positions. Plants used for foraging are divided into two categories: wild and cultivated. Due to the lack of forage plants in fall and winter, the local people mainly cultivate crops to feed their black-boned sheep. In addition, the black-boned sheep is an influential cultural species in the local community and plays a prominent role in the cultural identity of the Pumi people.

CONCLUSION

Sheep play an essential role in the inheritance of the spiritual culture and material culture of the Pumi ethnic group. The formation of the black-boned sheep is inseparable from the worship of sheep by the Pumi people. With a long-term grazing process, the locals have developed a variety of traditional knowledge related to black-boned sheep. This is the experience that locals have accumulated when managing forests and grasslands. Therefore, both the government and individuals should learn from the local people when it comes to protecting black-boned sheep. No one knows black-boned sheep better than them. The foremost evidence of this is the rich traditional knowledge of breeding black-boned sheep presented by key informants.

Characterization, expression profile, polymorphism and association of porcine NAT9 gene

The N-acetyltransferase 9 (NAT9) is an important reproduction related gene. In this study, we cloned the full-length cDNA sequence of porcine NAT9 gene through the rapid amplification of cDNA ends method. The porcine NAT9 gene encodes a protein of 206 amino acids which shares high homology with the NAT9 of seven species: rhesus monkey (87%), chimpanzee (87%), human (87%), horse (86%), rat (80%), mouse (79%) and gray short-tailed opossum (79%). This gene is structured in six exons and five introns as revealed by computer-assisted analysis. Tissue transcription profile analysis indicated that the porcine NAT9 gene is generally but differentially expressed in the detected tissues including spleen, large intestine, lung, fat, muscle, heart, liver, kidney and ovary. PCR-Alu I-RFLP was established to detect an A/G mutation on the position of 699-bp of mRNA and eight pig breeds display obvious genotype and allele frequency differences at this mutation locus. Association of this SNP with litter size traits was assessed in Large White (n = 100) and Landrace (n = 100) pig populations, and results demonstrated that this polymorphic locus is significantly associated with the litter size of first parity (P < 0.05). This suggests that the NAT9 gene can be an useful candidate gene in selection for increasing litter size in pigs.

A novel porcine gene, LIPC, differentially expressed in the liver tissues from Meishan and Large White pigs

The mRNA differential display technique was performed to investigate the differences in gene expression in the liver tissues from Meishan and Large White pigs. One novel gene that was differentially expressed was identified through semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and the cDNA complete sequence was then obtained using the rapid amplification of cDNA ends (RACE) method. The nucleotide sequence of the gene is not homologous to any of the known porcine genes. The sequence prediction analysis revealed that the open reading frame of this gene encoding a protein of 501 amino acids has high homology with the lipase, hepatic (LIPC) of seven species--cattle (82%), rhesus monkey (79%), chimpanzee (78%), rabbit (77%), human (78%), mouse (73%) and rat (72%)--so that it can be defined as the swine LIPC gene. Phylogenetic analysis revealed that the swine LIPC gene has a closer genetic relationship with the LIPC of cattle. Tissue expression profile analysis indicated that the swine LIPC gene is also differentially expressed in other detected tissues from Meishan and Large White pigs. Our experiment suggested that the swine LIPC gene might play an important role in the superabundant fat deposition of Chinese pigs.