Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Sci Food Agric ; 100(1): 325-334, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31584699

RESUMO

BACKGROUND: Meat fraud and adulteration incidents occur frequently in almost all regions of the globe, especially with the increase in the world's population. To ensure the authenticity of meat products, we developed a 10-plex xMAP assay to simultaneously detect ten animal materials: bovine, caprine, poultry, swine, donkey, deer, horse, dog, fox and mink. RESULTS: This method was investigated by analyzing DNA extracts from raw muscle, muscle mixtures, meat products and animal feeds. Our results indicated that the species of interest can be identified, differentiated and detected down to 1 g kg-1 in binary mixtures or 0.01-0.001 ng of genomic DNA from specific species. Testing of 125 commercial samples showed a 97.4% coincidence rate with the method used in routine testing in our lab. CONCLUSION: These results indicated that the method established in this study could detect ten animal materials simultaneously within 3 h, which provides a new, useful tool for animal ingredient analysis in meat products and animal feeds. © 2019 Society of Chemical Industry.


Assuntos
DNA Mitocondrial/genética , Contaminação de Alimentos/análise , Produtos da Carne/análise , Técnicas de Amplificação de Ácido Nucleico/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Ração Animal/análise , Animais , Bovinos , Cervos , Cães , Raposas , Cabras , Cavalos , Vison , Técnicas de Amplificação de Ácido Nucleico/instrumentação , Aves Domésticas , Suínos
2.
Biomed Pharmacother ; 117: 108986, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31387172

RESUMO

Chemokine-like factor 1 (CKLF1) is a cytokine, which has a detrimental effect on the multiple disease progression. Our previous studies reported that arterial injury induced the upregulation of CKLF1 expression in artery at 7-14 days after injury. Here, using a rat carotid balloon injury model, we found that CKLF1 knockdown in the injured site abolished neointimal formation and even decreased medial area; contrarily, CKLF1 overexpression developed a thicker neointima than controls, demonstrating that CKLF1 exerted positive effects on neointimal hyperplasia and the accumulation of vascular smooth muscle cells (VSMC). The mechanism study indicated that CKLF1 reduced susceptibility to the cell cycle G2/M arrest and apoptosis, and thereby speeding up VSMC accumulation. This role of CKLF1 was tightly associated with phosphatidylinositol (PI) 3-kinase signaling pathway. CKLF1 increased the expression of four isoforms of the PI3-kinase catalytic subunits, which in turn activated its downstream targets Akt and an effector NF-κB accepted as critical transcription factors of cell survival and proliferation. Furthermore, RNA-sequencing analysis revealed that CKLF1 had wide-ranging roles in regulating the expression of genes that mainly engaged in cell apoptosis and innate immune response. Collectively, the data allow us to conclude that high level CKLF1 after artery injury switches the balance of VSMC proliferation and apoptosis through PI3K/AKT/NF-κB signaling and consequently leads to neointimal hyperplasia. The findings shed insight into new treatment strategies to limit restenosis based on CKLF1 as a future target.


Assuntos
Apoptose/fisiologia , Quimiocinas/metabolismo , Hiperplasia/metabolismo , Proteínas com Domínio MARVEL/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Neointima/metabolismo , Transdução de Sinais/fisiologia , Animais , Divisão Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Pontos de Checagem da Fase G2 do Ciclo Celular/fisiologia , Hiperplasia/patologia , Masculino , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , NF-kappa B/metabolismo , Neointima/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley
3.
Appl Microbiol Biotechnol ; 103(11): 4575-4584, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31001745

RESUMO

The identification of animal species in feed and feedstuffs is important for detecting contamination and fraudulent replacement of animal components that might cause health and economic problems. A novel multiplex assay, based on xMAP technology and the generic detection of closely related species, was developed for the simultaneous differential detection of avian, fish, and ruminant DNA in products. Universal primers and probes specific to avian, fish, or ruminant species were designed to target a conserved mitochondrial DNA sequence in the 12S ribosomal RNA gene (rRNA). The assay specificity was validated using samples of 27 target and 10 nontarget animal species. The limits of detection of the purified DNA were determined to be 0.2 pg/µL-0.1 ng/µL by testing the meat samples of six species and four feedstuffs. The detection sensitivity of the experimental mixtures was demonstrated to be 0.01% (weight percentage). The assay's suitability for practical application was evaluated by testing feed samples; unlabeled animal ingredients were detected in 32% of the 56 samples. The assay differentially detected the three targeted categories of animal species in less than 2 h, reflecting improvements in speed and efficiency. Based on these results, this novel multiplex xMAP assay provides a reliable and highly efficient technology for the routine detection of animal species in feed and other products for which this information is needed.


Assuntos
Ração Animal/análise , DNA/isolamento & purificação , Contaminação de Alimentos , Hibridização de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase/métodos , Animais , Aves , DNA/genética , Primers do DNA/genética , Peixes , Sondas de Oligonucleotídeos/genética , RNA Ribossômico/genética , Ruminantes , Sensibilidade e Especificidade
4.
Int J Biol Sci ; 14(6): 667-681, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29904281

RESUMO

Vertnin (VRTN) variants are associated with thoracic vertebral number (TVN) in pigs. However, the biological function of VRTN remains poorly understood. Here we first conducted a range of experiments to demonstrate that VRTN is a responsible gene for TVN and two causative variants in the regulatory region of VRTN additively regulate TVN. Then, we show that VRTN is a novel DNA-binding transcription factor as it localizes exclusively in the nucleus, binds to DNA on a genome-wide scale and regulates the transcription of a set of genes that harbor VRTN binding motifs. Next, we illustrate that VRTN is essential for the development of thoracic vertebrae. Vrtn-null embryos display somitogenesis defect with the failure of axial rotation and fewer somites at the thoracic somite stage. Half of Vrtn heterozygous mice show abnormal spinal development with fewer thoracic vertebrae and ribs than their wild-type littermates. Lastly, we reveal that VRTN could modulate somite segmentation via the Notch signaling pathway. The findings advance our understanding of the mechanisms underlying the development of thoracic vertebrate in mammals, and VRTN causative variants provide a robust tool to improve pork production by selecting the alleles increasing the number of thoracic vertebrae and ribs.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Animais , Linhagem Celular , Recuperação de Fluorescência Após Fotodegradação , Imunofluorescência , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Células HEK293 , Heterozigoto , Humanos , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase em Tempo Real , Suínos
5.
Int J Biol Sci ; 13(5): 669-681, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28539839

RESUMO

Peroxisome proliferator-activated receptor beta/delta (PPARD) is an important determinant of multiple biological processes. Our previous studies identified a missense mutation in the PPARD gene that significantly reduces its transcription activity, and consequently causes enlarged external ears in pigs. However, the mechanisms underlying the causality has remained largely unknown. Here, we show that PPARD retards the development of auricular cartilage by accelerating the apoptosis of cartilage stem/progenitor cells (CSPCs), the terminal differentiation of cartilage cells and the degradation of cartilage extracellular matrix in the auricle. At the transcription level, PPARD upregulates a set of genes that are associated with CSPCs apoptosis and chondrogenic differentiation, chondroblast differentiation and extracellular matrix degradation. ChIP-seq identified direct target genes of PPARD, including a well-documented gene for cartilage development: PPARG. We further show that compared to wild-type PPARD, the G32E mutant up-regulates the expression of PPARG and subsequently leads to the downregulation of critical genes that inhibit cartilage growth. These findings allow us to conclude that PPARD is an inhibitor of auricular cartilage growth in pigs. The causative mutation (G32E) in the PPARD gene attenuates the PPARD-mediated retardation of cartilage growth in the auricle, contributing to enlarged ears in pigs. The findings advance our understanding of the mechanisms underlying auricular development in mammals, and shed insight into the studies of innate pinna disorders and cartilage regeneration medicine in humans.


Assuntos
Cartilagem/citologia , Orelha Externa/citologia , PPAR delta/farmacologia , Animais , Cartilagem/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Orelha Externa/efeitos dos fármacos , Humanos , Mutação/genética , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Suínos , Fatores de Transcrição/efeitos dos fármacos , Fatores de Transcrição/metabolismo
6.
J Vis Exp ; (122)2017 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-28448056

RESUMO

Studies on skeletal muscle physiology face the technical challenge of appropriately processing the specimens to obtain sections with clearly visible cytoplasmic compartments. Another hurdle is the tight apposition of myofibers to the surrounding tissues. Because the process of tissue fixation and paraffin embedding leads to the shrinkage of muscle fibers, freezing is an optimal means of hardening muscle tissue for sectioning. However, a commonly encountered issue, the formation of ice crystals, occurs during the preparation of frozen sections because of the high water content of muscle. The protocol presented here first describes a simple and efficient method for properly freezing muscle tissues by immersing them in liquid nitrogen. The problem with using liquid nitrogen alone is that it causes the formation of a nitrogen gas barrier next to the tissue, which acts as an insulator and inhibits the cooling of the tissues. To avoid this "vapor blanket" effect, a new cryovial was designed to increase the speed of liquid flow around the tissue surface. This was achieved by punching a total of 14 inlet holes in the wall of the vial. According to bubble dynamics, a higher rate of liquid flow results in smaller bubbles and fewer chances to form a gas barrier. When liquid nitrogen flows into the cryovial through the inlet holes, the flow velocity around the tissue is fast enough to eliminate the gas barrier. Compared to the method of freezing muscle tissues using pre-chilled isopentane, this protocol is simpler and more efficient and can be used to freeze muscle in a throughput manner. Furthermore, this method is optimal for institutions that do not have access to isopentane, which is extremely flammable at room temperature.


Assuntos
Artefatos , Congelamento , Secções Congeladas , Músculo Esquelético , Fixação de Tecidos/métodos , Preservação de Tecido/instrumentação , Preservação de Tecido/métodos , Desenho de Equipamento
7.
Physiol Genomics ; 48(8): 573-9, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27260842

RESUMO

Blood cell counts are important clinical indicators for health status. The liver plays a crucial role in food digestion and metabolism and is also a blood-forming organ. Here, we conducted a whole-genome quantitative trait transcript (QTT) analysis on 497 liver samples for 16 hematological traits in a White Duroc × Erhualian F2 pig resource population. A total of 20,108 transcripts were explored to detect their association with hematological traits. By using Spearman correlation coefficients, we identified 1,267 QTTs for these 16 hematological traits at the significance threshold of P < 0.001. We found 31 candidate genes for erythrocyte and leukocyte-related traits by a look-up of human and pig genome-wide association study results. Furthermore, we constructed coexpression networks for leukocyte-related QTTs using weighted gene coexpression analysis. These QTTs were clustered into two to eight modules. The highest connection strength in intramodules was identified in a module for white blood cell count. In the module, USP18, RSAD2, and OAS1 appeared to be important genes involved in interferon-stimulated innate immune system. The findings improve our understanding of intrinsic relationships between the liver and blood cells and provide novel insights into the potential therapeutic targets of hematologic diseases.


Assuntos
Células Sanguíneas/metabolismo , Fígado/metabolismo , Locos de Características Quantitativas/genética , Suínos/genética , Animais , Cruzamentos Genéticos , Eritrócitos/metabolismo , Feminino , Expressão Gênica/genética , Estudo de Associação Genômica Ampla/métodos , Doenças Hematológicas/genética , Leucócitos/metabolismo , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único/genética
8.
PLoS One ; 10(10): e0139583, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26430891

RESUMO

Sex determining region Y-box 9 (SOX9) is an important regulator of sex and skeletal development and is expressed in a variety of embryonal and adult tissues. Loss or gain of function resulting from mutations within the coding region or chromosomal aberrations of the SOX9 locus lead to a plethora of detrimental phenotypes in humans and animals. One of these phenotypes is the so-called male-to-female or female-to-male sex-reversal which has been observed in several mammals including pig, dog, cat, goat, horse, and deer. In 38,XX sex-reversal French Large White pigs, a genome-wide association study suggested SOX9 as the causal gene, although no functional mutations were identified in affected animals. However, besides others an 18 bp indel had been detected in the 5'-untranslated region of the SOX9 gene by comparing affected animals and controls. We have identified the same indel (Δ18) between position +247 bp and +266 bp downstream the transcription start site of the porcine SOX9 gene in four other pig breeds; i.e., German Large White, Laiwu Black, Bamei, and Erhualian. These animals have been genotyped in an attempt to identify candidate genes for porcine inguinal and/or scrotal hernia. Because the 18 bp segment in the wild type 5'-UTR harbours a highly conserved cAMP-response element (CRE) half-site, we analysed its role in SOX9 expression in vitro. Competition and immunodepletion electromobility shift assays demonstrate that the CRE half-site is specifically recognized by CREB. Both binding of CREB to the wild type as well as the absence of the CRE half-site in Δ18 reduced expression efficiency in HEK293T, PK-15, and ATDC5 cells significantly. Transfection experiments of wild type and Δ18 SOX9 promoter luciferase constructs show a significant reduction of RNA and protein levels depending on the presence or absence of the 18 bp segment. Hence, the data presented here demonstrate that the 18 bp indel in the porcine SOX9 5'-UTR is of functional importance and may therefore indeed be a causative variation in SOX9 associated traits.


Assuntos
Regiões 5' não Traduzidas/genética , Expressão Gênica , Mutação INDEL , Fatores de Transcrição SOX9/genética , Animais , Sequência de Bases , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Regulação da Expressão Gênica/fisiologia , Dados de Sequência Molecular , Biossíntese de Proteínas/genética , Fatores de Transcrição SOX9/metabolismo , Homologia de Sequência do Ácido Nucleico , Suínos , Transcrição Genética/genética
9.
PLoS One ; 8(9): e75925, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24058710

RESUMO

Peroxisome proliferator-activated receptor beta/delta (PPARD) is a crucial and multifaceted determinant of diverse biological functions including lipid metabolism, embryonic development, inflammatory response, wound healing and cancer. Recently, we proposed a novel function of porcine PPARD (sPPARD) in external ear development. A missense mutation (G32E) in an evolutionary conservative domain of sPPARD remarkably increases external ear size in pigs. Here, we investigated the underlying molecular mechanism of the causal mutation at the cellular level. Using a luciferase reporter system, we showed that the G32E substitution reduced transcription activity of sPPARD in a ligand-dependent manner. By comparison of the subcellular localization of wild-type and mutated sPPARD in both PK-15 cells and pinna cartilage-derived primary chondrocytes, we found that the G32E substitution promoted CRM-1 mediated nuclear exportation of sPPARD. With the surface plasmon resonance technology, we further revealed that the G32E substitution had negligible effect on its ligand binding affinity. Finally, we used co-immunoprecipitation and luciferase reporter assays to show that the G32E substitution greatly reduced ubiquitination level by blocking ubiquitination of the crucial A/B domain and consequently decreased transcription activity of sPPARD. Taken together, our findings strongly support that G32E is a functional variant that plays a key role in biological activity of sPPARD, which advances our understanding of the underlying mechanism of sPPARD G32E for ear size in pigs.


Assuntos
Núcleo Celular/metabolismo , Condrócitos/metabolismo , Mutação de Sentido Incorreto , PPAR delta/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Transporte Ativo do Núcleo Celular/fisiologia , Substituição de Aminoácidos , Animais , Linhagem Celular , Núcleo Celular/genética , Condrócitos/citologia , Orelha/anatomia & histologia , Orelha/crescimento & desenvolvimento , Humanos , Tamanho do Órgão/fisiologia , PPAR delta/genética , Suínos , Transcrição Genética/fisiologia
10.
Diagn Microbiol Infect Dis ; 77(1): 53-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23867326

RESUMO

A new assay with the combination of multiplex polymerase chain reaction and denaturing high-performance liquid chromatography analysis was developed for simultaneous detection of Mycobacterium genus and identification of the Mycobacterium tuberculosis complex (MTC). Targeting at genus-specific 16S rRNA sequence of Mycobacterium and specific insertion elements IS6110 and IS1081 of MTC, the assay was validated with 84 strains covering 23 mycobacteria species and 30 strains of non-mycobacteria species. No cross reactivity was observed. Clinical application was carried out on 198 specimens (155 human sputum and 43 bovine tissue samples) and compared with culture. The multiplex assay detected all culture-positive (36 in number) and 35.2% (57/162) culture-negative specimens. The molecular assay was fast that could be completed within 1 h on purified DNA, with the limit of detection as 0.8-1.6 pg per reaction on DNA template. This work provided a useful laboratory tool for rapid identification of Mycobacterium and differentiation of MTC and nontuberculous mycobacteria.


Assuntos
Técnicas Bacteriológicas/métodos , Cromatografia Líquida de Alta Pressão/métodos , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/diagnóstico , Tuberculose/microbiologia , Elementos de DNA Transponíveis , Humanos , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/genética , RNA Ribossômico 16S/genética , Sensibilidade e Especificidade , Fatores de Tempo
11.
PLoS One ; 8(5): e64047, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23724019

RESUMO

Thousands of QTLs for meat quality traits have been identified by linkage mapping studies, but most of them lack precise position or replication between populations, which hinder their application in pig breeding programs. To localize QTLs for meat quality traits to precise genomic regions, we performed a genome-wide association (GWA) study using the Illumina PorcineSNP60K Beadchip in two swine populations: 434 Sutai pigs and 933 F2 pigs from a White Duroc×Erhualian intercross. Meat quality traits, including pH, color, drip loss, moisture content, protein content and intramuscular fat content (IMF), marbling and firmness scores in the M. longissimus (LM) and M. semimembranosus (SM) muscles, were recorded on the two populations. In total, 127 chromosome-wide significant SNPs for these traits were identified. Among them, 11 SNPs reached genome-wise significance level, including 1 on SSC3 for pH, 1 on SSC3 and 3 on SSC15 for drip loss, 3 (unmapped) for color a*, and 2 for IMF each on SSC9 and SSCX. Except for 11 unmapped SNPs, 116 significant SNPs fell into 28 genomic regions of approximately 10 Mb or less. Most of these regions corresponded to previously reported QTL regions and spanned smaller intervals than before. The loci on SSC3 and SSC7 appeared to have pleiotropic effects on several related traits. Besides them, a few QTL signals were replicated between the two populations. Further, we identified thirteen new candidate genes for IMF, marbling and firmness, on the basis of their positions, functional annotations and reported expression patterns. The findings will contribute to further identification of the causal mutation underlying these QTLs and future marker-assisted selection in pigs.


Assuntos
Cruzamentos Genéticos , Estudo de Associação Genômica Ampla , Carne/normas , Sus scrofa/genética , Adiposidade/genética , Animais , China , Cor , Feminino , Concentração de Íons de Hidrogênio , Desequilíbrio de Ligação/genética , Masculino , Proteínas Musculares/metabolismo , Músculos/metabolismo , Polimorfismo de Nucleotídeo Único/genética
12.
BMC Genet ; 14: 46, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23725562

RESUMO

BACKGROUND: Porcine chromosome X harbors four QTL strongly affecting backfat thickness (BFT), ham weight (HW), intramuscular fat content (IMF) and loin eye area (LEA). The confidence intervals (CI) of these QTL overlap and span more than 30 cM, or approximately 80 Mb. This study therefore attempts to fine map these QTL by joint analysis of two large-scale F2 populations (Large White × Meishan and White Duroc × Erhualian constructed by INRA and JXAU respectively) and furthermore, to determine whether these QTL are caused by mutations in three positional candidate genes (ACSL4, SERPINA7 and IRS4) involved in lipid biosynthesis. RESULTS: A female-specific linkage map with an average distance of 2 cM between markers in the initial QTL interval (SW2456-SW1943) was created and used here. The CI of QTL for BFT, HW and LEA were narrowed down to 6-7 cM, resulting from the joint analysis. For IMF, two linked QTL were revealed in the INRA population but not in the JXAU population, causing a wider CI (13 cM) for IMF QTL. Linkage analyses using two subsets of INRA F1 dam families demonstrate that the BFT and HW QTL were segregating in the Meishan pigs. Moreover, haplotype comparisons between these dams suggest that within the refined QTL region, the recombination coldspot (~34 Mb) flanked by markers MCSE3F14 and UMNP1218 is unlikely to contain QTL genes. Two SNPs in the ACSL4 gene were identified and showed significant association with BFT and HW, but they and the known polymorphisms in the other two genes are unlikely to be causal mutations. CONCLUSION: The candidate QTL regions have been greatly reduced and the QTL are most likely located downstream of the recombination coldspot. The segregation of SSCX QTL for BFT and HW within Meishan breed provides an opportunity for us to make effective use of Meishan chromosome X in crossbreeding. Further studies should attempt to identify the impact of additional DNA sequence (e.g. CNV) and expression variation in the three genes or their surrounding genes on these traits.


Assuntos
Tecido Adiposo , Locos de Características Quantitativas , Suínos/genética , Cromossomo X , Animais , Sequência de Bases , Primers do DNA , Haplótipos , Reação em Cadeia da Polimerase
13.
J Sci Food Agric ; 93(5): 1206-10, 2013 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-23165775

RESUMO

BACKGROUND: Purchasing pork that is boned within 1 h postmortem and not aged is customary in China, and final pork color would not be fully realized. The relationship between early postmortem, pre-rigor meat color and 24 h postmortem, post-rigor pork color was investigated and related to the rate of pH and temperature decline within the longissimus dorsi (LD) and the semimembranosus (SM) muscles of pork carcasses. Muscle color, pH and temperature were measured at 45 min and at 3, 9, 15 and 24 h postmortem in carcasses of F2 White Duroc and Chinese Erhualian pigs. RESULTS: Pork color at 45 min postmortem was not indicative of that at 24 h postmortem in LD and SM, although muscle pH values and temperature at 45 min postmortem were significantly correlated with the LD and SM ultimate color. High muscle pH was associated with decreased L*, whereas high muscle temperature increased L*. Muscle pH and temperature had little effect on a* and b* in LD and color evolution in SM. CONCLUSIONS: Results indicated that meat color inspected shortly after slaughter does not reflect post-rigor meat quality.


Assuntos
Dieta/etnologia , Qualidade dos Alimentos , Armazenamento de Alimentos , Carne/análise , Modelos Químicos , Músculo Esquelético/química , Animais , Castração , China , Cruzamentos Genéticos , Feminino , Concentração de Íons de Hidrogênio , Masculino , Pigmentação , Análise de Regressão , Sus scrofa , Temperatura Ambiente , Fatores de Tempo
14.
PLoS Genet ; 7(5): e1002043, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21573137

RESUMO

Chinese Erhualian is the most prolific pig breed in the world. The breed exhibits exceptionally large and floppy ears. To identify genes underlying this typical feature, we previously performed a genome scan in a large scale White Duroc × Erhualian cross and mapped a major QTL for ear size to a 2-cM region on chromosome 7. We herein performed an identical-by-descent analysis that defined the QTL within a 750-kb region. Historically, the large-ear feature has been selected for the ancient sacrificial culture in Erhualian pigs. By using a selective sweep analysis, we then refined the critical region to a 630-kb interval containing 9 annotated genes. Four of the 9 genes are expressed in ear tissues of piglets. Of the 4 genes, PPARD stood out as the strongest candidate gene for its established role in skin homeostasis, cartilage development, and fat metabolism. No differential expression of PPARD was found in ear tissues at different growth stages between large-eared Erhualian and small-eared Duroc pigs. We further screened coding sequence variants in the PPARD gene and identified only one missense mutation (G32E) in a conserved functionally important domain. The protein-altering mutation showed perfect concordance (100%) with the QTL genotypes of all 19 founder animals segregating in the White Duroc × Erhualian cross and occurred at high frequencies exclusively in Chinese large-eared breeds. Moreover, the mutation is of functional significance; it mediates down-regulation of ß-catenin and its target gene expression that is crucial for fat deposition in skin. Furthermore, the mutation was significantly associated with ear size across the experimental cross and diverse outbred populations. A worldwide survey of haplotype diversity revealed that the mutation event is of Chinese origin, likely after domestication. Taken together, we provide evidence that PPARD G32E is the variation underlying this major QTL.


Assuntos
Orelha Externa/anatomia & histologia , Mutação de Sentido Incorreto/genética , PPAR delta/genética , Locos de Características Quantitativas/genética , Suínos/anatomia & histologia , Suínos/genética , Alelos , Sequência de Aminoácidos , Animais , Cruzamento , China , Mapeamento Cromossômico , Regulação para Baixo/genética , Feminino , Regulação da Expressão Gênica/genética , Frequência do Gene , Estudos de Associação Genética , Variação Genética/genética , Haplótipos , Masculino , Dados de Sequência Molecular , PPAR delta/química , Alinhamento de Sequência , Transdução de Sinais/genética , beta Catenina/genética , beta Catenina/metabolismo
15.
BMC Genomics ; 11: 159, 2010 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-20211033

RESUMO

BACKGROUND: Variations in recombination fraction (theta) among chromosomal regions, individuals and families have been observed and have an important impact on quantitative trait loci (QTL) mapping studies. Such variations on porcine chromosome X (SSC-X) and on other mammalian chromosome X are rarely explored. The emerging assembly of pig sequence provides exact physical location of many markers, facilitating the study of a fine-scale recombination landscape of the pig genome by comparing a clone-based physical map to a genetic map. Using large offspring of F1 females from two large-scale resource populations (Large White male symbol x Chinese Meishan female symbol, and White Duroc male symbol x Chinese Erhualian female symbol), we were able to evaluate the heterogeneity in theta for a specific interval among individual F1 females. RESULTS: Alignments between the cytogenetic map, radiation hybrid (RH) map, genetic maps and clone map of SSC-X with the physical map of human chromosome X (HSA-X) are presented. The most likely order of 60 markers on SSC-X is inferred. The average recombination rate across SSC-X is of approximately 1.27 cM/Mb. However, almost no recombination occurred in a large region of approximately 31 Mb extending from the centromere to Xq21, whereas in the surrounding regions and in the Xq telomeric region a recombination rate of 2.8-3.3 cM/Mb was observed, more than twice the chromosome-wide average rate. Significant differences in theta among F1 females within each population were observed for several chromosomal intervals. The largest variation was observed in both populations in the interval UMNP71-SW1943, or more precisely in the subinterval UMNP891-UMNP93. The individual variation in theta over this subinterval was found associated with F1 females' maternal haplotypes (Chinese pig haplotypes) and independent of paternal haplotype (European pig haplotypes). The theta between UMNP891 and UMNP93 for haplotype 1122 and 4311 differed by more than fourteen-fold (10.3% vs. 0.7%). CONCLUSIONS: This study reveals marked regional, individual and haplotype-specific differences in recombination rate on SSC-X. Lack of recombination in such a large region makes it impossible to narrow QTL interval using traditional fine-mapping approaches. The relationship between recombination variation and haplotype polymorphism is shown for the first time in pigs.


Assuntos
Recombinação Genética , Sus scrofa/genética , Cromossomo X/genética , Animais , Feminino , Ligação Genética , Variação Genética , Genética Populacional , Haplótipos , Humanos , Meiose , Repetições de Microssatélites , Mapeamento de Híbridos Radioativos , Alinhamento de Sequência
16.
Behav Genet ; 39(2): 213-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19130209

RESUMO

Maternal behavior around parturition is important to piglet survival. An extreme form of failure of maternal behavior, also called maternal infanticide, often occurs in some sows. This is defined as an active attack to piglets using the jaws, resulting in serious or fatal bite wounds within 24 h of birth. It leads to considerable economic losses to the pig industry and severe problems in pig welfare. In this study, maternal behaviors from 5 h before to 24 h after parturition were recorded in detail on 288 White Duroc x Erhualian intercross F(2) sows over their three continuous farrowings. In the F(2) population 12.8% gilts showed maternal infanticide in their first litter, while the incidences of maternal infanticide at their second and third farrowing reduced to 7.5% and 4.5%, respectively. All F(2) sows were genotyped for 194 microsatellite markers spanning the whole pig genome. A whole genome linkage analysis was performed using the non-parametric linkage test by SimWalk2 software. The results identified that seven chromosome regions on SSC2, SSC6, SSC14, SSC15 and SSCX were significantly linked with maternal infanticide (P < 0.05). The quantitative trait loci (QTL) on SSC2 and SSCX achieved P < 0.01 significance level. The most promising QTLs, however, were detected on X chromosome where three peaks of negative logarithm of P-value located at marker SW980, SW2456 and SW1608. QTLs on SSC2 and SSCX from this experiment were consistent with published results from the Western commercial lines.


Assuntos
Comportamento Animal , Locos de Características Quantitativas , Sus scrofa/genética , Animais , Cruzamentos Genéticos , Feminino , Genoma , Genótipo , Comportamento Materno , Repetições de Microssatélites , Modelos Genéticos , Fenótipo , Software
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA