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Introduction: The ban on antibiotics in animal husbandry underscores the crucial need for safe, natural feed additives. This study investigates the effects of Ampelopsis grossedentata flavonoids (AGF) and Tween 80 on the growth performance, blood indexes, and rumen microbiota of Nubian goats, evaluating their potential as alternative feed additives in livestock management. Methods: Thirty-two goats were randomly divided into four groups. The control group (CON group) was provided with a basal diet, while the experimental groups received diets supplemented with various dietary additives for a duration of 100 days: either a basal diet supplemented with 25 mg/kg of monensin (MN group), a basal diet containing 2.0 g/kg of Ampelopsis grossedentata flavonoids (AGF group), or a basal diet containing 7.5 mL/kg of Tween 80 (TW group). Blood and rumen fluid samples were collected for analysis at the end of the feeding period. Growth performance was monitored through regular weighing and feed intake measurements. Blood indexes were analyzed using standard biochemical techniques, while the microbial composition of the rumen fluid was determined through high throughput 16S rRNA gene sequencing to assess microbial diversity and function. The effects of the dietary treatments on growth performance, blood indexes, and rumen microbial composition were then evaluated. Results: The AGF group exhibited significantly increased average daily gain, and decreased feed-to-gain ratio (p < 0.05). Blood indexes analysis revealed no differences between the CON and AGF groups, with both showing higher concentrations of triglyceride, low-density lipoprotein cholesterol, glutamic-pyruvic transaminase, alkaline phosphatase, and lactate dehydrogenase compared to the monensin group (p < 0.05). The TW group had significantly higher glucose, glutamic-oxaloacetic transaminase, and glutamic-pyruvic transaminase levels than the MN group (p < 0.05). Microbial diversity analysis revealed that the TW group had significantly greater alpha-diversity than other groups, while beta-diversity analysis showed closer similarity between the rumen microbiota of the AGF and CON groups. LEfSe analysis identified Proteobacteria, Deferribacteres, Ehryarchaeoia, and Elusimicrobia as biomarkers distinguishing the rumen microbiota among the groups. In conclusion, AGF supplementation increased the relative abundance of beneficial bacteria in the rumen of Nubian goats, and thus enhanced the growth performance. TW supplementation significantly increased rumen microbial diversity and abundance, suggesting benefits for rumen health despite poor palatability. These findings highlight the potential of AGF as a new green additive with important implications for the efficiency and development of animal husbandry.
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At present, there are few reports about the proteomics changes provoked by butylated hydroxytoluene (BHT) supplementation on cryopreserved semen in mammals. Thus, we aimed to evaluate the effects of different concentrations of BHT on goat sperm and to investigate the proteomics changes of adding BHT to cryopreserved goat (Capra hircus) sperm. Firstly, semen samples were collected from four goats, and frozen in the basic extenders containing different concentrations of BHT (0.5 mM, 1.0 mM, 2.0 mM) and a control without BHT, respectively. After thawing, the protective effects of dose-dependent replenished BHT to the freezing medium on post-thaw sperm motility, integrities of plasma membrane and acrosome, reactive oxygen species levels were confirmed, with 0.5 mM BHT being the best (B group) as compared to the control (without BHT, C group). Afterwards, TMT-based quantitative proteomic technique was performed to profile proteome of the goat sperm between C group and B group. Parallel reaction monitoring was used to confirm reliability of the data. Overall, 2,476 proteins were identified and quantified via this approach. Comparing the C and B groups directly (C vs. B), there were 17 differentially abundant proteins (DAPs) po-tentially associated with sperm characteristics and functions were identified, wherein three were upregulated and 14 were downregulated, respectively. GO annotation analysis demonstrated the potential involvement of the identified DAPs in metabolic process, multi-organism process, reproduction, reproductive process, and cellular process. KEGG enrichment analysis further indicated their potential roles in renin-angiotensin system and glutathione metabolism pathways. Together, this novel study clearly shows that BHT can effectively improve quality parameters and fertility potential of post-thawed goat sperm at the optimal concentration, and its cryoprotection may be realized through regulation of sperm metabolism and antioxidative capability from the perspective of sperm proteomic modification.
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Antioxydants , Butylhydrotoluène , Cryoconservation , Capra , Protéomique , Conservation de semence , Mobilité des spermatozoïdes , Spermatozoïdes , Animaux , Mâle , Cryoconservation/méthodes , Cryoconservation/médecine vétérinaire , Butylhydrotoluène/pharmacologie , Spermatozoïdes/effets des médicaments et des substances chimiques , Spermatozoïdes/métabolisme , Conservation de semence/méthodes , Conservation de semence/médecine vétérinaire , Protéomique/méthodes , Antioxydants/pharmacologie , Antioxydants/métabolisme , Mobilité des spermatozoïdes/effets des médicaments et des substances chimiques , Espèces réactives de l'oxygène/métabolisme , Protéome/effets des médicaments et des substances chimiques , Protéome/métabolismeRÉSUMÉ
Beef is a major global source of protein, playing an essential role in the human diet. The worldwide production and consumption of beef continue to rise, reflecting a significant trend. However, despite the critical importance of beef cattle resources in agriculture, the diversity of cattle breeds faces severe challenges, with many breeds at risk of extinction. The initiation of the Beef Cattle Genome Project is crucial. By constructing a high-precision functional annotation map of their genome, it becomes possible to analyze the genetic mechanisms underlying important traits in beef cattle, laying a solid foundation for breeding more efficient and productive cattle breeds. This review details advances in genome sequencing and assembly technologies, iterative upgrades of the beef cattle reference genome, and its application in pan-genome research. Additionally, it summarizes relevant studies on the discovery of functional genes associated with key traits in beef cattle, such as growth, meat quality, reproduction, polled traits, disease resistance, and environmental adaptability. Finally, the review explores the potential of telomere-to-telomere (T2T) genome assembly, structural variations (SVs), and multi-omics techniques in future beef cattle genetic breeding. These advancements collectively offer promising avenues for enhancing beef cattle breeding and improving genetic traits.
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Génome , Animaux , Bovins/génétique , Génomique/méthodes , Sélection/méthodes , Séquençage du génome entier/méthodes , Viande rouge , Locus de caractère quantitatifRÉSUMÉ
The Chungtien schizothoracin (Ptychobarbus chungtienensis), an endangered fish species endemic to the Zhongdian Plateau, remains underexplored in terms of transcriptomic sequencing. This investigation used tissues from five distinct organs (heart, liver, spleen, kidney, and brain) of the Chungtien schizothoracin for PacBio Iso-seq and RNA-seq analyses, yielding a repertoire of 16,598 full-length transcripts spanning lengths from 363 bp to 7,157 bp. Gene family clustering and phylogenetic analysis encompassed a comprehensive set of 13 fish species, all of which were cyprinids, including the zebrafish and the examined species Ptychobarbus chungtienensis. Moreover, the identification of long non-coding RNAs (lncRNAs) and coding sequences was accomplished across all five tissues. Comprehensive analyses of gene expression profiles and differentially expressed genes among the above five tissues were performed. In summary, the obtained full-length transcripts and detailed gene expression profiles of the Chungtien schizothoracin tissues furnish crucial expression data and genetic sequences, laying the groundwork for future investigations and fostering a holistic comprehension of the adaptive mechanisms inherent in the Chungtien schizothoracin under various conditions.
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Cyprinidae , Phylogenèse , Transcriptome , Animaux , Cyprinidae/génétique , RNA-Seq , ARN long non codant/génétique , Espèce en voie de disparitionRÉSUMÉ
Multi-omics-integrated analysis, known as panomics, represents an advanced methodology that harnesses various high-throughput technologies encompassing genomics, epigenomics, transcriptomics, proteomics, and metabolomics. Sheep, playing a pivotal role in agricultural sectors due to their substantial economic importance, have witnessed remarkable advancements in genetic breeding through the amalgamation of multiomics analyses, particularly with the evolution of high-throughput technologies. This integrative approach has established a robust theoretical foundation, enabling a deeper understanding of sheep genetics and fostering improvements in breeding strategies. The comprehensive insights obtained through this approach shed light on diverse facets of sheep development, including growth, reproduction, disease resistance, and the quality of livestock products. This review primarily focuses on the application of principal omics analysis technologies in sheep, emphasizing correlation studies between multiomics data and specific traits such as meat quality, wool characteristics, and reproductive features. Additionally, this paper anticipates forthcoming trends and potential developments in this field.
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Preadipocyte differentiation represents a critical stage in adipogenesis, with mitochondria playing an undeniable pivotal role. Given the intricate interplay between transcription and metabolic signaling during adipogenesis, the regulation of sirtuin 5 (SIRT5) on mitochondrial function and lipid metabolism was revealed via multiple omics analysis. The findings suggest that SIRT5 plays a crucial role in promoting mitochondrial biosynthesis and maintaining mitochondrial function during preadipocyte differentiation. Moreover, SIRT5 modulates the metabolic levels of numerous bioactive substances by extensively regulating genes expression associated with differentiation, energy metabolism, lipid synthesis, and mitochondrial function. Finally, SIRT5 was found to suppress triacylglycerols (TAG) accumulation while enhancing the proportion and diversity of unsaturated fatty acids, and providing conditions for the expansion and stability of membrane structure during mitochondrial biosynthesis through numerous gene regulations. Our findings provide a foundation for the identification of crucial functional genes, signaling pathways, and metabolic substances associated with adipose tissue differentiation and metabolism.
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Métabolisme lipidique , Sirtuines , Bovins , Animaux , Sirtuines/génétique , Sirtuines/métabolisme , Adipogenèse , Mitochondries/génétique , Tissu adipeux/métabolismeRÉSUMÉ
The solute transport protein family 11 A1 (SLC11A1), also recognized as natural resistance-associated macrophage protein 1 (NRAMP1), represents a transmembrane protein encoded by the SLC11A1 gene. A variety of prior investigations have illuminated its involvement in conferring resistance or susceptibility to bacterial agents, positioning it as a promising candidate gene for breeding disease-resistant animals. Yaks (Bos grunniens), renowned inhabitants of the Qinghai-Tibet Plateau in China, stand as robust ruminants distinguished by their adaptability and formidable disease resistance. Notwithstanding these unique traits, there is scant literature on the SLC11A1 gene in the yak population. Our inquiry commences with the cloning of the 5' regulatory region sequence of the Zhongdian yak SLC11A1 gene. We employ bioinformatics tools to identify transcription factor binding sites, delineating pivotal elements like enhancers and cis-acting elements. To ascertain the promoter activity of this region, we amplify four distinct promoter fragments within the 5' regulatory region of the yak SLC11A1 gene. Subsequently, we design a luciferase reporter gene vector containing four site-specific deletion mutations and perform transient transfection experiments. Through these experiments, we measure and compare the activity of disparate gene fragments located within the 5' regulatory region, revealing regions bearing promoter functionality and discerning key regulatory elements. Our findings validate the promoter functionality of the 5' regulatory region, offering preliminary insights into the core and principal regulatory segments of this promoter. Notably, we identified single nucleotide polymorphisms (SNPs) that may be associated with important regulatory elements such as NF-1 and NF-1/L. This study provides a theoretical framework for in-depth research on the function and expression regulation mechanism of the yak SLC11A1 gene.
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Bovine spongiform encephalopathy (BSE) is a fatal disease in cattle caused by misfolded prion proteins and linked to indel polymorphisms in the promoter and intron 1 of the PRNP gene. The aim of this study was to determine the allele, genotype, and haplotype frequencies of PRNP indel polymorphisms and to investigate the effect of PRNP gene expressions of 23 bp and 12 bp indels via polymerase chain reaction (PCR) in Zhongdian Yak (Bos-grunniens) (YK), Zhongdian Yellow cattle (Bos-taurus) (YC), and Zhongdian Yakow (Bos-primigenius taurus × Bos-grunniens) (PK). Resultant high allelic frequencies were found in 23- and 12+, while haplotype frequencies were very low in 23+/12 in YK, YC, and PK. PRNP expression was higher in the +-/-- diplotype of the PK and (mean ± SE) was 3.6578 ± 1.85964. Furthermore, two variable sites were investigated-a 23 bp indel polymorphism holding AP1 binding site and a 12 bp indel polymorphism holding SP1 binding site. Additionally, reporter gene assays revealed a link between two proposed transcription factors and lower expression levels of the +/+ allele compared with the -/- allele. The expression level of PRNP was shown to be dependent on two indel polymorphisms in the bovine PRNP promoter, which includes binding sites for RP58 and SP1 transcription factors. These findings raised the possibility that the PRNP genotype may contribute to the high variation in PRNP expression.
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As an exemplary model for examining molecular mechanisms responsible for extreme phenotypic variations, plumage color has garnered significant interest. The Cygnus genus features two species, Cygnus olor and Cygnus atratus, that exhibit striking disparities in plumage color. However, the molecular foundation for this differentiation has remained elusive. Herein, we present two high-quality genomes for C. olor and C. atratus, procured using the Illumina and Nanopore technologies. The assembled genome of C. olor was 1.12 Gb in size with a contig N50 of 26.82 Mb, while its counterpart was 1.13 Gb in size with a contig N50 of 21.91 Mb. A comparative analysis unveiled three genes (TYR, SLC45A2, and SLC7A11) with structural variants in the melanogenic pathway. Notably, we also identified a novel gene, PWWP domain containing 2A (PWWP2A), that is related to plumage color, for the first time. Using targeted gene modification analysis, we demonstrated the potential genetic effect of the PWWP2A variant on pigment gene expression and melanin production. Finally, our findings offer insight into the intricate pattern of pigmentation and the role of polygenes in birds. Furthermore, these two high-quality genome references provide a comprehensive resource and perspective for comparative functional and genetic studies of evolution within the Cygnus genus.
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Oiseaux , Génome , Animaux , GénomiqueRÉSUMÉ
Introduction: Body measurement traits are integral in cattle production, serving as pivotal criteria for breeding selection. Wenshan cattle, a local breed in China's Yunnan province, exhibit remarkable genetic diversity. However, the molecular mechanisms regulating body measurement traits in Wenshan cattle remain unexplored. Methods: In this study, we performed a genome-wide association method to identify genetic architecture for body height body length hip height back height (BAH), waist height and ischial tuberosity height using the Bovine 50 K single nucleotide polymorphism Array in 1060 Wenshan cattles. Results: This analysis reveals 8 significant SNPs identified through the mixed linear model (MLM), with 6 SNPs are associated with multiple traits and 4 SNPs are associated with all 6 traits. Furthermore, we pinpoint 21 candidate genes located in proximity to or within these significant SNPs. Among them, Scarb1, acetoacetyl-CoA synthetase and HIVEP3 were implicated in bone formation and rarely encountered in livestock body measurement traits, emerge as potential candidate genes regulating body measurement traits in Wenshan cattle. Discussion: This investigation provides valuable insights into the genetic mechanisms underpinning body measurement traits in this unique cattle breed, paving the way for further research in this domain.
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Chinese indicine cattle harbor a much higher genetic diversity compared with other domestic cattle, but their genome architecture remains uninvestigated. Using PacBio HiFi sequencing data from 10 Chinese indicine cattle across southern China, we assembled 20 high-quality partially phased genomes and integrated them into a multiassembly graph containing 148.5 Mb (5.6%) of novel sequence. We identified 156,009 high-confidence nonredundant structural variants (SVs) and 206 SV hotspots spanning â¼195 Mb of gene-rich sequence. We detected 34,249 archaic introgressed fragments in Chinese indicine cattle covering 1.93 Gb (73.3%) of the genome. We inferred an average of 3.8%, 3.2%, 1.4%, and 0.5% of introgressed sequence originating, respectively, from banteng-like, kouprey-like, gayal-like, and gaur-like Bos species, as well as 0.6% of unknown origin. Introgression from multiple donors might have contributed to the genetic diversity of Chinese indicine cattle. Altogether, this study highlights the contribution of interspecies introgression to the genomic architecture of an important livestock population and shows how exotic genomic elements can contribute to the genetic variation available for selection.
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Bovins , Ruminants , Animaux , Bovins/génétique , Chine , Génome , Génomique , Ruminants/génétiqueRÉSUMÉ
This study was conducted to evaluate the influences of supplementing Ampelopsis grossedentata flavonoids (AGF) on the rumen bacterial microbiome, plasma physiology and biochemistry, and growth performance of goats. Twenty-four Nubian kids were randomly allocated to three dietary treatments: the control (CON, basal diet), the 1.0 g/kg AGF treatment (AGF), and the 12.5 mg/kg monensin treatment (MN). This trial consisted of 10 days for adaptation and 90 days for data and sample collection. The results reveal that Bacteroidetes, Firmicutes, and Proteobacteria are the dominant phyla in kids' rumen. Compared with the CON group, the alpha diversity in the MN and AGF groups significantly increased (p < 0.01). Beta-diversity shows that rumen microbial composition is more similar in the MN and AGF groups. LEfSe analysis shows that Prevotella_1 in the AGF group were significantly higher than those in the MN and CON group. The high-density lipoprotein cholesterol and glucose levels in the AGF group were significantly higher than those in the CON group (p < 0.05), whereas the low-density lipoprotein cholesterol, glutamic-pyruvic transaminase, and alkaline phosphatase levels exhibited the opposite trend. The average daily gains in the AGF and MN groups significantly increased, while the feed-to-gain ratios were significantly decreased (p < 0.05). The results suggest that adding AGF to the diet improves microbial composition and has important implications for studying juvenile livestock growth and improving economic benefits.
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Structural variations (SVs) are a major contributor to genetic diversity and phenotypic variations, but their prevalence and functions in domestic animals are largely unexplored. Here we generated high-quality genome assemblies for 15 individuals from genetically diverse sheep breeds using Pacific Biosciences (PacBio) high-fidelity sequencing, discovering 130.3 Mb nonreference sequences, from which 588 genes were annotated. A total of 149,158 biallelic insertions/deletions, 6531 divergent alleles, and 14,707 multiallelic variations with precise breakpoints were discovered. The SV spectrum is characterized by an excess of derived insertions compared to deletions (94,422 vs. 33,571), suggesting recent active LINE expansions in sheep. Nearly half of the SVs display low to moderate linkage disequilibrium with surrounding single-nucleotide polymorphisms (SNPs) and most SVs cannot be tagged by SNP probes from the widely used ovine 50K SNP chip. We identified 865 population-stratified SVs including 122 SVs possibly derived in the domestication process among 690 individuals from sheep breeds worldwide. A novel 168-bp insertion in the 5' untranslated region (5' UTR) of HOXB13 is found at high frequency in long-tailed sheep. Further genome-wide association study and gene expression analyses suggest that this mutation is causative for the long-tail trait. In summary, we have developed a panel of high-quality de novo assemblies and present a catalog of structural variations in sheep. Our data capture abundant candidate functional variations that were previously unexplored and provide a fundamental resource for understanding trait biology in sheep.
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Étude d'association pangénomique , Queue , Animaux , Ovis/génétique , Régions 5' non traduites , Allèles , PhénotypeRÉSUMÉ
Determining the functional consequences of karyotypic changes is invariably challenging because evolution tends to obscure many of its own footprints, such as accumulated mutations, recombination events, and demographic perturbations. Here, we describe the assembly of a chromosome-level reference genome of the gayal (Bos frontalis) thereby revealing the structure, at base-pair-level resolution, of a telo/acrocentric-to-telo/acrocentric Robertsonian translocation (2;28) (T/A-to-T/A rob[2;28]). The absence of any reduction in the recombination rate or genetic introgression within the fusion region of gayal served to challenge the long-standing view of a role for fusion-induced meiotic dysfunction in speciation. The disproportionate increase noted in the distant interactions across pro-chr2 and pro-chr28, and the change in open-chromatin accessibility following rob(2;28), may, however, have led to the various gene expression irregularities observed in the gayal. Indeed, we found that many muscle-related genes, located synthetically on pro-chr2 and pro-chr28, exhibited significant changes in expression. This, combined with genome-scale structural variants and expression alterations in genes involved in myofibril composition, may have driven the rapid sarcomere adaptation of gayal to its rugged mountain habitat. Our findings not only suggest that large-scale chromosomal changes can lead to alterations in genome-level expression, thereby promoting both adaptation and speciation, but also illuminate novel avenues for studying the relationship between karyotype evolution and speciation.
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Chromatine , Génome , Animaux , BovinsRÉSUMÉ
Among the numerous transmissible spongiform encephalopathies (TSEs), bovine spongiform encephalopathy (BSE) is the most well-known TSEs. It is a potential Creutzfeldt-Jakob (CJD) disease mutation that can be transferred through cattle to humans. In several animals, the prion protein gene (PRNP) is recognized to take active part in TSE vulnerability or tolerance. Previous studies have found indels polymorphism in PRNP gene promoter and intron1 region linked to BSE vulnerability. It's linked with 23 bp indels polymorphism in putative promoter and 12 bp indel in intron 1 of the PRNP gene. The aim of this study was to compare the allele, genotype and haplotype frequencies of PRNP indel polymorphisms in Zhongdian Yak (Bos grunniens) (YK), Zhongdian Yellow cattle (Bos taurus) (YC) and Zhongdian Yakow (Bos primigenius taurus × Bos grunniens) (PK) with worldwide reported healthy or affected BSE cattle, in order to assess their potential resistance to BSE. A comparison of Chinese bovine populations with healthy and BSE-affected German and Swiss cattle from globally was conducted, and result indicating significant difference (p < .001) between healthy and affected cattle. Additionally, as compared to prior studies with Chinese bovine population, the significant results were found. In this study, the allelic frequency D23 finding high deletion in all analyzed Chinese bovine species, and haplotype D12-D23 exhibited a less significant inclination toward susceptibility to BSE.
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Maladies des bovins , Encéphalopathie spongiforme bovine , Prions , Animaux , Bovins/génétique , Encéphalopathie spongiforme bovine/génétique , Fréquence d'allèle/génétique , Polymorphisme génétique/génétique , Protéines prion/génétique , Prions/génétiqueRÉSUMÉ
The Y chromosome plays key roles in male fertility and reflects the evolutionary history of paternal lineages. Here, we present a de novo genome assembly of the Hu sheep with the first draft assembly of ovine Y chromosome (oMSY), using nanopore sequencing and Hi-C technologies. The oMSY that we generated spans 10.6 Mb from which 775 Y-SNPs were identified by applying a large panel of whole genome sequences from worldwide sheep and wild Iranian mouflons. Three major paternal lineages (HY1a, HY1b and HY2) were defined across domestic sheep, of which HY2 was newly detected. Surprisingly, HY2 forms a monophyletic clade with the Iranian mouflons and is highly divergent from both HY1a and HY1b. Demographic analysis of Y chromosomes, mitochondrial and nuclear genomes confirmed that HY2 and the maternal counterpart of lineage C represented a distinct wild mouflon population in Iran that diverge from the direct ancestor of domestic sheep, the wild mouflons in Southeastern Anatolia. Our results suggest that wild Iranian mouflons had introgressed into domestic sheep and thereby introduced this Iranian mouflon specific lineage carrying HY2 to both East Asian and Africa sheep populations.
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Évolution biologique , Ovis aries/génétique , Séquençage du génome entier/méthodes , Chromosome Y/génétique , Animaux , Variation génétique , Mâle , PhylogenèseRÉSUMÉ
Lanping black-boned sheep was first discovered in the 1950s in Lanping county of China and characterized by black pigmentation on skin and internal organs. Due to the novel and unique trait, the genetic background of Lanping black-boned sheep is of great interest. Here, we genotyped genome-wide SNPs (single nucleotide polymorphisms) of Lanping black-boned sheep and Lanping normal sheep using Illumina OvineSNP50 BeadChip to investigate the genetic diversity and genetic origin of Lanping black-boned sheep. We also downloaded a subset SNP dataset of two Tibet-lineage sheep breeds and four other sheep breeds from the International Sheep Genomics Consortium (ISGC) as a reference for interpreting. Lanping black-boned sheep had a lower genetic diversity level when compared to seven other sheep breeds. Principal component analysis (PCA) showed that Lanping black-boned sheep and Lanping normal sheep were clustered into the Asian group, but there was no clear separation between the two breeds. Structure analysis demonstrated a high ancestry coefficient in Lanping black-boned sheep and Lanping normal sheep. However, the two populations were separated into two distinct branches in a neighbor-joining (NJ) tree. We further evaluated the genetic divergence using population F ST , which showed that the genetic differentiation that existed between Lanping black-boned sheep and Lanping normal sheep was higher than that between Tibet sheep and Changthangi sheep, which revealed that Lanping black-boned sheep is a different breed from Lanping normal sheep on the genetic level. In addition, structure analysis and NJ tree showed that Lanping black-boned sheep had a relatively close relation with Tibet sheep. The results reported herein are a first step toward understanding the genetic background of Lanping black-boned sheep, and it will provide informative knowledge on the unique genetic resource conservation and mechanism of novel breed formation.
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Divergence of gene expression and alternative splicing is a crucial driving force in the evolution of species; to date, however the molecular mechanism remains unclear. Hybrids of closely related species provide a suitable model to analyze allele-specific expression (ASE) and allele-specific alternative splicing (ASS). Analysis of ASE and ASS can uncover the differences in cis-regulatory elements between closely related species, while eliminating interference of trans-regulatory elements. Here, we provide a detailed characterization of ASE and ASS from 19 and 10 transcriptome datasets across five tissues from reciprocal-cross hybrids of horse×donkey (mule/hinny) and cattle×yak (dzo), respectively. Results showed that 4.8%-8.7% and 10.8%-16.7% of genes exhibited ASE and ASS, respectively. Notably, lncRNAs and pseudogenes were more likely to show ASE than protein-coding genes. In addition, genes showing ASE and ASS in mule/hinny were found to be involved in the regulation of muscle strength, whereas those of dzo were involved in high-altitude adaptation. In conclusion, our study demonstrated that exploration of genes showing ASE and ASS in hybrids of closely related species is feasible for species evolution research.
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Allèles , Épissage alternatif , Bovins/génétique , Equidae/génétique , Hybridation génétique/génétique , Animaux , Séquence nucléotidique , Régulation de l'expression des gènes , ARN/génétique , ARN/métabolismeRÉSUMÉ
Resistance to fatal disease bovine spongiformencephalopathy (BSE), due to misfolded prion protein in cattle, is associated with a 23-bp indel polymorphism in the putative promoter and a 12-bp indel in intron 1 of the PRNP gene. Gayal (Bos frontalis) is an important semiwild bovid species and of great conservation concern, but till today these indel polymorphisms have not been evaluated in gayals. Therefore, we collected 225 samples of gayals and evaluated the genetic indel polymorphism in the two regions of this PRNP gene. The results revealed high allelic frequencies of insertions at these indel sites: 0.909 and 0.667 for, respectively, the 23 bp and 12 bp indels, both also with significant genotype frequencies (χ2: 9.81; 23 bp and χ2: 43.56; 12 bp). At the same time, the haplotype data showed indel polymorphisms with extremely low deletion (0.01) in both regions of the PRNP gene. We compared these data with those reported for healthy and BSE-affected cattle (Bos taurus) breeds from two European countries, Germany and Switzerland, and significant difference (P <0.001) was observed between BSE-affected as well as the healthy cattle. Further, our data were also extensively compared with previous reports on BSE and highly significant (P<0.001) outcomes were observed. This result suggested negligible genetic susceptibility to BSE in gayals. To the best of our knowledge, this study is the first comprehensive deciphering information about the PRNP indel polymorphisms of 23 bp and 12 bp in gayals, a semiwild species of China.
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Encéphalopathie spongiforme bovine/génétique , Prédisposition génétique à une maladie , Mutation de type INDEL , Polymorphisme génétique , Protéines prion/génétique , Animaux , Bovins , Chine , HaplotypesRÉSUMÉ
BACKGROUND: Black bone sheep was first discovered in Yunnan province of China in 1970, with unique black pigmentation on the body and internal organs. Endothelin 3 (EDN3) has been known as a key gene causing hyperpigmentation in black bone chicken, the Silky fowl. METHODS: In this study, EDN3 was employed as a candidate gene for regulating black color pigmentation. First, EDN3 was cloned from sheep to obtain the full-length cDNA by using the rapid amplification of cDNA ends (RACE). Genomic EDN3 was screened and a total of thirty predicted single nucleotide polymorphisms (SNPs) were genotyped for allele and genotype frequency analysis in a case-control study involving two black bone sheep populations. Genomic copy number analysis of EDN3 in sheep was conducted to measure the variation in copy number. EDN3 expression levels were observed among the groups in adult liver, lymph node, and kidney tissues, as well as embryo kidney samples. Also, among the tissues of black bone and non-black bone sheep. RESULTS: The size of the full-length cDNA was 1,578 bp, which included 426 bp of 5'-untranslated region (5'-UTR), an open reading frame (ORF) of 639 bp encoding a protein of 212 amino acids, and a 3'-UTR of 513 bp. Genotype and allele frequencies of all the discovered SNPs were found insignificantly different in black bone and non-black bone sheep (P > 0.05). Genomic copy number analysis of EDN3 in sheep revealed no significant difference between the two sheep groups. No significant variations were found in the adult liver and kidney embryo samples. However, the expression in lymph node and kidney tissue was significantly higher in black bone sheep than that in non-black bone sheep (P < 0.05). Significant variations in the EDN3 expression levels were observed among the tissues of non-black bone sheep. CONCLUSIONS: The findings of the present study indicate that unlike in Silky chickens, EDN3 is not responsible for hyperpigmentation but may play a key functional role in immune and excretory systems of black bone sheep.