The melanocortin receptor 1 (MC1R) plays a central role in regulation of animal coat color formation. In this study, we sequenced the complete coding region and parts of the 5′‐ and 3′‐untranslated regions of the MC1R gene in Chinese sheep with completely white (Large‐tailed Han sheep), black (Minxian Black‐fur sheep), and brown coat colors (Kazakh Fat‐Rumped sheep). The results showed five single nucleotide polymorphisms (SNPs): two non‐synonymous mutations previously associated with coat color (c.218 T>A, p.73 Met>Lys. c.361 G>A, p.121 Asp>Asn) and three synonymous mutations (c.429 C>T, p.143 Tyr>Tyr; c.600 T>G, p.200 Leu>Leu. c.735 C>T, p.245 Ile>Ile). Meanwhile, all mutations were detected in Minxian Black‐fur sheep. However, the two nonsynonymous mutation sites were not in all studied breeds (Large‐tailed Han, Small‐tailed Han, Gansu Alpine Merino, and China Merino breeds), all of which are in white coat. A single haplotype AATGT (haplotype3) was uniquely associated with black coat color in Minxian Black‐fur breed (P = 9.72E − 72, chi‐square test). The first and second A alleles in this haplotype 3 represent location at 218 and 361 positions, respectively. Our results suggest that the mutations of MC1R gene are associated with black coat color phenotype in Chinese sheep.
18 September 2018 in Indian Journal of Animal Research
Animal coloration is a powerful model for studying the genetic mechanisms that determine animal phenotypes. But, there has not been comprehensive characterization of the molecular basis of the complex patterns of coat color phenotype variation in wild boars. This study results indicated that the wild-type allele E+ of the MC1R gene was a dominant allele in wild boars and was not responsible for black, brown or other coat color phenotypes. A novel mutation c.695 T > C was identified in the 3¢-UTR of the ASIP gene. The association analysis showed that the C mutation allele was highly significantly associated with wild-type coat colors between wild boars and Western pig breeds (P=1.35E-33). A non-synonymous g.2254 G > A substitution was found in exon 2 of the TYRP1 gene (p.143His>Arg). The association analysis demonstrated that the G mutation allele was also significantly associated with wild-type coat colors between wild boars and Western pig breeds (P = 5.09E-10). In short, a few mutation sites in MC1R, ASIP, and TYRP1 genes were identified and surveyed several polymorphisms molecular variations in Chinese wild boars. In our identified mutations have caused the morphological diversity in wild boars, but did not influence coat color phenotype variation in some domesticated pig breeds. The conclusion was obtained that some mutations in color-associated genes were associated with wild-type coat colors in wild boar population, and that similar coat colorations observed in domesticated pig and wild boars can be the product of underlying differences in the genetic basis of color variants.
A detailed understanding of microbial ecology in different supraglacial habitats is important due to the unprecedented speed of glacier retreat. Differences in bacterial diversity and community structure between glacial snow and glacial soil on the Chongce Ice Cap were assessed using 454 pyrosequencing. Based on rarefaction curves, Chao1, ACE, and Shannon indices, we found that bacterial diversity in glacial snow was lower than that in glacial soil. Principal coordinate analysis (PCoA) and heatmap analysis indicated that there were major differences in bacterial communities between glacial snow and glacial soil. Most bacteria were different between the two habitats; however, there were some common bacteria shared between glacial snow and glacial soil. Some rare or functional bacterial resources were also present in the Chongce Ice Cap. These findings provide a preliminary understanding of the shifts in bacterial diversity and communities from glacial snow to glacial soil after the melting and inflow of glacial snow into glacial soil.
Commensal microorganisms are essential to the normal development and function of many aspects of animal biology, including digestion, nutrient absorption, immunological development, behaviors, and evolution. The specific microbial composition and evolution of the intestinal tracts of wild pigs remain poorly characterized. This study therefore sought to assess the composition, distribution, and evolution of the intestinal microbiome of wild pigs. For these analyses, 16S rRNA V3-V4 regions from five gut sections prepared from each of three wild sows were sequenced to detect the microbiome composition. These analyses revealed the presence of 6,513 operational taxonomic units (OTUs) mostly distributed across 17 phyla and 163 genera in these samples, with Firmicutes and Actinobacteria being the most prevalent phyla of microbes present in cecum and jejunum samples, respectively. Moreover, the abundance of Actinobacteria in wild pigs was higher than that in domestic pigs. At the genus level the Bifidobacterium and Allobaculum species of microbes were most abundant in all tested gut sections, with higher relative abundance in wild pigs relative to domestic pigs, indicating that in the process of pig evolution, the intestinal microbes also evolved, and changes in the intestinal microbial diversity could have been one of the evolutionary forces of pigs. Intestinal microbial functional analyses also revealed the microbes present in the small intestine (duodenum, jejunum, and ileum) and large intestine (cecum and colon) of wild pigs to engage distinct metabolic spatial structures and pathways relative to one another. Overall, these results offer unique insights that would help to advance the current understanding of how the intestinal microbes interact with the host and affect the evolution of pigs.
The intestinal microbiota plays significant role in the physiology and functioning of host organisms. However, there is limited knowledge of the composition and evolution of microbiota-host relationships from wild ancestors to modern domesticated species. In this study, the 16S rRNA gene V3–V4 in the intestinal contents of different pig breeds was analyzed and was compared using high-throughput sequencing. This identified 18 323 amplicon sequence variants, of which the Firmicutes and Actinobacteria phyla and Bifidobacterium and Allobaculum genera were most prevalent in wild pigs (WP). In contrast, Proteobacteria and Firmicutes predominated in Chinese Shanxi Black pigs (CSB), while Firmicutes were the most prevalent phylum in Large White pigs (LW) and Iberian pigs (IB), followed by Bacteroidetes in IB and Proteobacteria in LW. At the genus level, Shigella and Lactobacillus were most prevalent in CSB and LW, while Actinobacillus and Sarcina predominated in IB. Differential gene expression together with phylogenetic and functional analyses indicated significant differences in the relative abundance of microbial taxa between different pig breeds. Although many microbial taxa were common to both wild and domestic pigs, significant diversification was observed in bacterial genes that potentially influence host phenotypic traits. Overall, these findings suggested that both the composition and functions of the microbiota were closely associated with domestication and the evolutionary changes in the host. The members of the microbial communities were vertically transmitted in pigs, with evidence of co-evolution of both the hosts and their intestinal microbial communities. These results enhance our understanding and appreciation of the complex interactions between intestinal microbes and hosts and highlight the importance of applying this knowledge in agricultural and microbiological research.
Tail adipose deposition in sheep is an economically significant trait that has an impact on meat quality and reproductive performance. This study elucidates the regulatory mechanism of FGFBP1 in the proliferation and differentiation of ovine tail-derived preadipocytes. Overexpression and knockdown methods were used to establish gain- and loss-of-function models, and the biological effects of FGFBP1 on adipocyte dynamics were systematically assessed. FGFBP1 overexpression significantly inhibited cellular proliferation by cell cycle arrest in the G2/M phase, and, at the same time, promoted adipocyte differentiation by upregulating key adipogenic markers (PPARγ, Adiponectin, C/EBPα, and FABP4). In contrast, gene silencing enhanced the proliferative capacity and decreased lipid droplet accumulation, confirming its inhibitory role in adipogenesis. Our findings indicate that FGFBP1 is a key regulator of tail adipogenesis. This discovery enhances our understanding of the mechanisms of adipocyte differentiation and provides theoretical bases and potential therapeutic targets for optimizing lipid deposition traits in livestock production.