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1.
J Dairy Sci ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39004123

RESUMEN

The bovine Major Histocompatibility Complex (MHC), also known as the Bovine Leucocyte Antigen (BoLA) complex, is the genomic region that encodes the most important molecules for antigen presentation to initiate immune responses. The first evidence of MHC in bovines pointed to a locus containing 2 antigens, one detected by cytotoxic antiserum (MHC class I) and another studied by mixed lymphocyte culture tests (MHC class II). The most studied gene in the BoLA region is the highly polymorphic BoLA-DRB3, which encodes a ß chain with a peptide groove domain involved in antigen presentation for T cells that will develop and co-stimulate cellular and humoral effector responses. BoLA-DRB3 alleles have been associated with outcomes in infectious diseases such as mastitis, trypanosomiasis, and tick loads, and with production traits. To catalog these alleles, 2 nomenclature methods were proposed, and the current use of both systems makes it difficult to list, comprehend and apply these data effectively. In this review we have organized the knowledge available in all of the reports on the frequencies of BoLA-DRB3 alleles. It covers information from studies made in at least 26 countries on more than 30 breeds; studies are lacking in countries that are important producers of cattle livestock. We highlight practical applications of BoLA studies for identification of markers associated with resistance to infectious and parasitic diseases, increased production traits and T cell epitope mapping, in addition to genetic diversity and conservation studies of commercial and creole and locally adapted breeds. Finally, we provide support for the need of studies to discover new BoLA alleles and uncover unknown roles of this locus in production traits.

2.
Trop Anim Health Prod ; 55(6): 413, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37994941

RESUMEN

The aim of this study was to evaluate the effect of the polymorphic FecGE allele on reproductive traits in Santa Inês and Morada Nova ewes. The traits evaluated were as follows: total progeny weights at birth (PWB) and weaning (PWW) and progeny survival rates at birth (PSRB) and weaning (PSRW). A total of 389 animals, belonging to two Santa Inês herds and one Morada Nova herd, were genotyped. There was a difference between the averages for all the traits studied regarding type of parturition, herd/breed, genotype/herd, and genotype/type of parturition. For each additional progeny, if the female was FecGE/E, the PWB decreased by 1.02 kg and the PWW by 3.16 kg, also with a 0.04% reduction in PSRB and no change in PSRW. If the female was FecGE/+, the reduction in PWB was 0.24 kg, with an increase in PSRW by 0.11%, but no change in PWW and PSRB. In general, these results demonstrate that FecG+/+ females have a better ability to increase their number of progenies without reducing PWB and PWW (also similar to FecGE/+). Thus, it is suggested that further studies on the association between the traits of interest and candidate genes in sheep should be carried out so that the regions which have the greatest effect on the expression of these traits are actually identified. It was not possible to verify the effect of the FecGE allele on the PWB, PWW, PSRB, and PSRW in these Morada Nova and Santa Inês herds.


Asunto(s)
Parto , Femenino , Animales , Ovinos/genética , Embarazo , Brasil , Genotipo , Fenotipo , Alelos
3.
Genet Mol Biol ; 43(3): e20190324, 2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32870232

RESUMEN

Cross-species hybridizations have been extensively used to generate animals and plants better suited for draft and food and fiber production since Roman times, and are still important in current agricultural practices with growing uses especially in aquaculture. Diagnostic tools based on marker panels with sufficient numbers of markers for accurate identification of cross-species hybrid individuals from intercrossed and backcrossed populations are increasingly necessary for practical, accurate species-purity certification and management of commercial broodstocks. Minimal numbers of di-allelic markers with species-specific alleles required to accurately identify hybrid individuals in intercrossed and advanced backcrossed populations were estimated using power analysis, and ranged from 5 to 191 (α = .05), and from 7 to 293 (α = .01), considering backcross 1 (BC1) to BC6 populations, respectively. Numbers of markers required for accurate hybrid identification observed in simulated BC1 to BC6 populations ranged from 5 to 1,131 and 7 to 8,065, considering error rates ≤ 5% and ≤ 1%, respectively. Estimated and observed numbers of diagnostic markers required for accurate hybrid identification up to four generations of backcrossing fall within practical operational limits of most commercial platforms currently available for genotyping low-density SNP marker panels. Therefore, cost-effective assay panels could be developed to provide practical tools for accurate species-purity certification.

4.
Genet Mol Biol ; 43(4): e20200006, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33174977

RESUMEN

In the present study, the complete characterization of cDNA and genomic sequences of IL-1ß and IL-8, as well as the expression profile of these genes in the South American fish pacu (Piaractus mesopotamicus) is provided. The full-length pmIL-1ß cDNA was composed of 1208 nucleotides that would produce a precursor peptide with 273 amino acid residues. A putative caspase-1 cleavage site, similar to what is found in mammalian IL-1ß, was identified producing a mature peptide with a theoretical molecular weight of 17.21 kDa. The pmIL-8 cDNA sequence consisted of 1019 nucleotides which encoded a 95-amino acid protein with a theoretical molecular weight of 10.43 kDa that showed all typical CXC chemokine features, including a 20-residue signal peptide and four conserved cysteine residues. Constitutive mRNA expression was detected for both genes in the liver, head kidney, gill, intestine, skin and spleen. After a bacterial challenge, up-regulation was detected for both pmIL-1ß and pmIL-8 in the spleen and head kidney at 12 h post-infection. At 24 h post-infection there was a decrease in the expression of both genes, with pmIL-8 showing a significant down-regulation in the liver and head kidney when compared to the control groups.

5.
Reprod Domest Anim ; 54(9): 1217-1229, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31269288

RESUMEN

This study aimed to characterize the gene expression, lipid composition and DNA methylation reprogramming during in vitro maturation (IVM) of pig oocytes with different developmental competencies. We used prepubertal gilts and cycling sows as a model to obtain oocytes with different levels of competency. We found that genes involved in lipid metabolism, SLC27A4, CPT2 and PLIN2, and DNA methylation, DNMT3A, TET1 and TET3, possessed altered transcript expression levels during IVM. Specifically, SLC27A4 mRNA (p = 0.05) increased in oocytes from cycling females, whereas CPT2 (p = 0.05), PLIN2 (p = 0.02) and DNMT3A (p = 0.02) increased in oocytes from prepubertal females during IVM. Additionally, TET3 mRNA increased during IVM in oocytes from prepubertal (p = 0.0005) and cycling females (p = 0.02). The TET1 transcript decreased (p = 0.05) during IVM in oocytes from cycling sows. Regarding lipid composition, mass spectrometry revealed a cluster of ions, with molecular masses higher than m/z 700, which comprises a group of complex phospholipids, was identified in all groups of oocytes, except in those from prepubertal gilts. With respect to DNA methylation reprogramming, it was noted that the less competent oocytes were not able to reprogramme the XIST gene during IVM. We conclude that the maternal mRNA store, lipid composition and epigenetic reprogramming are still being established during maturation and are related to oocyte competence. In addition, we propose that the methylation pattern of the XIST may be used as molecular marker for oocyte competence in pigs.


Asunto(s)
Metilación de ADN , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Oocitos/metabolismo , Porcinos/crecimiento & desarrollo , Animales , Femenino , Regulación del Desarrollo de la Expresión Génica , Lípidos/análisis , Oocitos/citología , Fosfolípidos/análisis , ARN Mensajero/metabolismo , Maduración Sexual , Porcinos/genética , Porcinos/metabolismo
6.
Fish Shellfish Immunol ; 74: 94-100, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29277697

RESUMEN

Nitric oxide (NO) is an important effector molecule which is involved in a myriad of biological processes, including immune responses against pathogens such as parasites, virus and bacteria. During the inflammatory processes in vertebrates, NO is produced by the inducible nitric oxide synthase (iNOS) enzyme in practically all nucleated cells to suppress or kill intracellular pathogens. The aim of the present study was to characterize the full coding region of the iNOS gene of pacu (Piaractus mesopotamicus), an economically and ecologically important South American fish species, and to analyze mRNA expression levels following intraperitoneal infection with the pathogenic bacterium Aeromonas dhakensis by means of quantitative real time PCR (qPCR). The results showed that the pacu iNOS transcript is 3237 bp in length, encoding a putative protein composed of 1078 amino acid residues. The amino acid sequence showed similarities ranging from 69.03% to 94.34% with other teleost fish and 57.70% with the human iNOS, with all characteristic domains and cofactor binding sites of the enzyme detected. Phylogenetic analysis showed that the iNOS from the red-bellied piranha, another South American characiform, was the closest related sequence to the pacu iNOS. iNOS transcripts were constitutively detected in the liver, spleen and head kidney, and there was a significant upregulation in the liver and spleen at 12, 24 and 48 h after infection with A. dhakensis. No significant variations were observed in the head kidney during the periods analyzed. These results show that iNOS expression was induced by A. dhakensis infection and suggest that this enzyme may be involved in the response to this bacterium in pacu.


Asunto(s)
Characiformes/genética , Characiformes/inmunología , Enfermedades de los Peces/inmunología , Regulación de la Expresión Génica/inmunología , Inmunidad Innata/genética , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/inmunología , Inmunidad Adaptativa , Aeromonas/inmunología , Secuencia de Aminoácidos , Animales , Proteínas de Peces/química , Proteínas de Peces/genética , Proteínas de Peces/inmunología , Perfilación de la Expresión Génica , Infecciones por Bacterias Gramnegativas/inmunología , Óxido Nítrico Sintasa de Tipo II/química , Filogenia , Distribución Aleatoria , Alineación de Secuencia/veterinaria
7.
Genetica ; 145(1): 51-66, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28160169

RESUMEN

The cachara (Pseudoplatystoma reticulatum) is a Neotropical freshwater catfish from family Pimelodidae (Siluriformes) native to Brazil. The species is of relative economic importance for local aquaculture production and basic biological information is under development to help boost efforts to domesticate and raise the species in commercial systems. The complete cachara mitochondrial genome was obtained by assembling Illumina RNA-seq data from pooled samples. The full mitogenome was found to be 16,576 bp in length, showing the same basic structure, order, and genetic organization observed in other Pimelodidae, with 13 protein-coding genes, 2 rNA genes, 22 trNAs, and a control region. Observed base composition was 24.63% T, 28.47% C, 31.45% A, and 15.44% G. With the exception of NAD6 and eight tRNAs, all of the observed mitochondrial genes were found to be coded on the H strand. A total of 107 SNPs were identified in P. reticulatum mtDNA, 67 of which were located in coding regions. Of these SNPs, 10 result in amino acid changes. Analysis of the obtained sequence with 94 publicly available full Siluriformes mitogenomes resulted in a phylogenetic tree that generally agreed with available phylogenetic proposals for the order. The first report of the complete Pseudoplatystoma reticulatum mitochondrial genome sequence revealed general gene organization, structure, content, and order similar to most vertebrates. Specific sequence and content features were observed and may have functional attributes which are now available for further investigation.


Asunto(s)
Bagres/clasificación , Bagres/genética , Genoma Mitocondrial , Filogenia , Animales , Composición de Base , Secuencia de Bases , Codón , Biología Computacional/métodos , Genes Mitocondriales , Secuenciación de Nucleótidos de Alto Rendimiento , Anotación de Secuencia Molecular , Polimorfismo de Nucleótido Simple
8.
BMC Genomics ; 17: 454, 2016 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-27297173

RESUMEN

BACKGROUND: Copy number variations (CNVs) have been shown to account for substantial portions of observed genomic variation and have been associated with qualitative and quantitative traits and the onset of disease in a number of species. Information from high-resolution studies to detect, characterize and estimate population-specific variant frequencies will facilitate the incorporation of CNVs in genomic studies to identify genes affecting traits of importance. RESULTS: Genome-wide CNVs were detected in high-density single nucleotide polymorphism (SNP) genotyping data from 1,717 Nelore (Bos indicus) cattle, and in NGS data from eight key ancestral bulls. A total of 68,007 and 12,786 distinct CNVs were observed, respectively. Cross-comparisons of results obtained for the eight resequenced animals revealed that 92 % of the CNVs were observed in both datasets, while 62 % of all detected CNVs were observed to overlap with previously validated cattle copy number variant regions (CNVRs). Observed CNVs were used for obtaining breed-specific CNV frequencies and identification of CNVRs, which were subsequently used for gene annotation. A total of 688 of the detected CNVRs were observed to overlap with 286 non-redundant QTLs associated with important production traits in cattle. All of 34 CNVs previously reported to be associated with milk production traits in Holsteins were also observed in Nelore cattle. Comparisons of estimated frequencies of these CNVs in the two breeds revealed 14, 13, 6 and 14 regions in high (>20 %), low (<20 %) and divergent (NEL > HOL, NEL < HOL) frequencies, respectively. CONCLUSIONS: Obtained results significantly enriched the bovine CNV map and enabled the identification of variants that are potentially associated with traits under selection in Nelore cattle, particularly in genome regions harboring QTLs affecting production traits.


Asunto(s)
Variaciones en el Número de Copia de ADN , Genoma , Genómica , Sitios de Carácter Cuantitativo , Carácter Cuantitativo Heredable , Animales , Bovinos , Mapeo Cromosómico , Biología Computacional/métodos , Estudio de Asociación del Genoma Completo , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Anotación de Secuencia Molecular , Polimorfismo de Nucleótido Simple , Reproducibilidad de los Resultados
9.
Genet Mol Biol ; 37(1): 54-60, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24688291

RESUMEN

Brazilian goats are generally kept in small herds and extensive rearing systems, mainly in the northeastern region of the country. Despite production improvement in recent years, the lack of pedigree control has affected genetic progress. This study aimed to validate a panel of 16 microsatellites for parentage testing in locally adapted and commercial goats breeds raised in Brazil, as well as to compare its efficiency with the panel recommended by the Brazilian Ministry of Agriculture, Livestock and Supplies (MAPA) in 2004. The number of alleles and expected heterozygosity (He) per marker ranged from four to 18, and from 0.051 to 0.831, respectively. Using all markers, 100% of parentage cases of the validation dataset were resolved with a strict confidence level of 95%. The 16 microsatellites panel showed adequate exclusion power (99.99%) and identity accuracy (99.99%). Suggestions for improvement of the marker panel endorsed by MAPA are provided.

10.
Infect Genet Evol ; 121: 105599, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38679113

RESUMEN

Whopping cough (or Pertussis) is an acute infectious respiratory disease caused by Bordetella pertussis bacteria. The disease is highly transmissible and can be fatal in children under two years old. Since the introduction of vaccine immunization in 1940, Pertussis incidence decreased worldwide. In Brazil, the immunization was introduced in 1977 using the whole cell (wP) vaccine. Despite the high vaccination coverage, an unexpected increase in the number of observed Pertussis cases was observed in 2012. In this year, 2257 cases were reported exceeding the average incidence rate of <1000 cases per year until 2010. This outbreak reached a peak level in 2014 and ended in 2018 according to the Brazilian National Surveillance System (SINAN). To understand the relationship between the outbreak and the vaccination, bacterial isolates (n = 136) from the Brazilian Midwest region obtained during the outbreak were submitted to genotyping of two vaccine loci: ptxP and fim3. Most of isolates (102) were obtained from nursing children (29 days to 2 years old). Genotyping of 94 isolates revealed that fim3-24/ptxP-3 was the most prevalent genotype (68%) associated with the outbreak peak. Two additional genotypes were also observed: fim3-1/ptxP-3 (15%) and fim3-3/ptxP-3 (17%). Conversely, the fim3-1/ptxP-2 genotype, which is harbored by the strain used in the wP vaccine (Bp137), was not observed. These results showed that B. pertussis circulating strains in the outbreak analyzed were different from the strain used for Pertussis immunization in Brazil. These observations provide insights that could be used to target vaccination programs to prevent future whooping cough outbreaks in Brazil.


Asunto(s)
Bordetella pertussis , Brotes de Enfermedades , Genotipo , Vacuna contra la Tos Ferina , Tos Ferina , Brasil/epidemiología , Humanos , Tos Ferina/epidemiología , Tos Ferina/prevención & control , Tos Ferina/microbiología , Bordetella pertussis/genética , Bordetella pertussis/inmunología , Bordetella pertussis/clasificación , Vacuna contra la Tos Ferina/inmunología , Vacuna contra la Tos Ferina/administración & dosificación , Lactante , Preescolar , Femenino , Masculino , Recién Nacido , Niño , Antígenos Bacterianos , Factores de Virulencia de Bordetella , Proteínas Fimbrias
11.
J Equine Vet Sci ; 126: 104251, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36796740

RESUMEN

Optimization of DNA collection for National gene bank and conservation programs requires information on spatial and genetic distribution of animals countrywide. The relationship between genetic and geographic distances were examined in 8 Brazilian horse breeds (Baixadeiro, Crioulo, Campeiro, Lavradeiro, Marajoara, Mangalarga Marchador, Pantaneiro and Puruca) using Single Nucleotide Polymorphism markers and collection point locations. Mantel correlations, Genetic Landscape Shape Interpolation, Allelic Aggregation Index Analyses and Spatial autocorrelation tests indicated a nonrandom distribution of horses throughout the country. Minimum collection distances for the national Gene Bank should be 530km, with clear divisions seen in genetic structure of horse populations in both North/South and East/West directions. Comparing Pantaneiro and North/Northeastern breeds, physical distance is not necessarily the defining factor for genetic differentiation. This should be considered when sampling these local breeds. These data can help optimise GenBank collection routines and conservation strategies for these breeds.


Asunto(s)
Variación Genética , Animales , Caballos/genética , Variación Genética/genética , Brasil
12.
Anim Reprod ; 20(1): e20220076, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36938311

RESUMEN

The establishment of epigenetic marks during the reprogramming window is susceptible to environmental influences, and stimuli during this critical stage can cause altered DNA methylation in offspring. In a previous study, we found that low levels of sulphur and cobalt (low S/Co) in the diet offered to oocyte donors altered the DNA methylome of bovine embryos. However, due to the extensive epigenetic reprogramming that occurs during embryogenesis, we hypothesized that the different methylation regions (DMRs) identified in the blastocysts may not maintain in adulthood. Here, we aimed to characterize DMRs previously identified in embryos, in the blood and sperm of adult progenies of two groups of heifers (low S/Co and control). We used six bulls and characterized the DNA methylation levels of KDM2A, KDM5A, KMT2D, and DOT1L genes. Our results showed that all DMRs analysed in both groups and tissues were hypermethylated unlike that noticed in the embryonic methylome profiles. These results suggest that embryo DMRs were reprogrammed during the final stages of de novo methylation during embryogenesis or later in development. Therefore, due to the highly dynamic epigenetic state during early embryonic development, we suggest that is essential to validate the DMRs found in embryos in adult individuals.

13.
Zygote ; 20(3): 281-90, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21492504

RESUMEN

The embryonic developmental block occurs at the 8-cell stage in cattle and is characterized by a lengthening of the cell cycle and an increased number of embryos that stop development. The maternal-embryonic transition arises at the same stage resulting in the transcription of many genes. Gene expression studies during this stage may contribute to the understanding of the physiological mechanisms involved in the maternal-embryonic transition. Herein we identified genes differentially expressed between embryos with high or low developmental competence to reach the blastocyst stage using differential display PCR. Embryos were analysed according to developmental kinetics: fast cleavage embryos showing 8 cells at 48 h post insemination (hpi) with high potential of development (F8), and embryos with slow cleavage presenting 4 cells at 48 hpi (S4) and 8 cells at 90 hpi (S8), both with reduced rates of development to blastocyst. The fluorescence DDPCR method was applied and allowed the recovery of 176 differentially expressed bands with similar proportion between high and low development potential groups (52% to F8 and 48% in S4 and S8 groups). A total of 27 isolated fragments were cloned and sequenced, confirming the expected primer sequences and allowing the identification of 27 gene transcripts. PI3KCA and ITM2B were chosen for relative quantification of mRNA using real-time PCR and showed a kinetic and a time-related pattern of expression respectively. The observed results suggest the existence of two different embryonic genome activation mechanisms: fast-developing embryos activate genes related to embryonic development, and slow-developing embryos activate genes related to cellular survival and/or death.


Asunto(s)
Embrión de Mamíferos/metabolismo , Regulación del Desarrollo de la Expresión Génica , Animales , Bovinos , Ciclo Celular , Femenino , Fertilización In Vitro , Perfilación de la Expresión Génica , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , ARN Mensajero/metabolismo
14.
iScience ; 25(4): 104005, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35313691

RESUMEN

Commercial poultry operations produce and crowd billions of birds every year, which is a source of inexpensive animal protein. Commercial poultry is intensely bred for desirable production traits, and currently presents very low variability at the major histocompatibility complex. This situation dampens the advantages conferred by the MHC's high genetic variability, and crowding generates immunosuppressive stress. We address the proteins of influenza A viruses directly and indirectly involved in host specificities. We discuss how mutants with increased virulence and/or altered host specificity may arise if few class I alleles are the sole selective pressure on avian viruses circulating in immunocompromised poultry. This hypothesis is testable with peptidomics of MHC ligands. Breeding strategies for commercial poultry can easily and inexpensively include high variability of MHC as a trait of interest, to help save billions of dollars as a disease burden caused by influenza and decrease the risk of selecting highly virulent strains.

15.
Genes (Basel) ; 14(1)2022 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-36672811

RESUMEN

Small ruminant lentiviruses (SRLVs) affect sheep and goats worldwide. The major gene related to SRLV infections is the Transmembrane Protein Gene 154 (TMEM154). We estimated the haplotype frequencies of TMEM154 in the USA (USDA-ARS) and Brazil (Embrapa) Gene Banks by using two different SNP genotyping methodologies, FluidigmTM and KASPTM. We also genotyped the ZNF389_ss748775100 deletion variant in Brazilian flocks. A total of 1040 blood samples and 112 semen samples from 15 Brazilian breeds were genotyped with Fluidigm for the SNP ZNF389_ss748775100 and 12 TMEM154 SNPs. A total of 484 blood samples from the Santa Inês breed and 188 semen samples from 14 North American sheep breeds were genotyped with KASP for 6 TMEM154 SNPs. All the Brazilian samples had the "I/I" genotype for the ZNF389_ss748775100 mutation. There were 25 TMEM154 haplotypes distributed across the Brazilian breeds, and 4 haplotypes in the US breeds. Haplotypes associated with susceptibility were present in almost all breeds, which suggests that genetic testing can help to improve herd health and productivity by selecting non-susceptible animals as founders of the next generations. Fluidigm and KASP are reliable assays when compared with Beadchip arrays. Further studies are necessary to understand the unknown role of TMEM154 mutations, host-pathogen interaction and new genes associated with the clinical condition.


Asunto(s)
Lentivirus , Enfermedades de las Ovejas , Ovinos/genética , Animales , Lentivirus/genética , Brasil , Enfermedades de las Ovejas/genética , Mutación , Pruebas Genéticas
16.
Immunogenetics ; 63(5): 319-24, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21301827

RESUMEN

Bovines present contrasting, heritable phenotypes of infestations with the cattle tick, Rhipicephalus (Boophilus) microplus. Tick salivary glands produce IgG-binding proteins (IGBPs) as a mechanism for escaping from host antibodies that these ectoparasites ingest during blood meals. Allotypes that occur in the constant region of IgG may differ in their capacity to bind with tick IGBPs; this may be reflected by the distribution of distinct allotypes according to phenotypes of tick infestations. In order to test this hypothesis, we investigated the frequency of haplotypes of bovine IgG2 among tick-resistant and tick-susceptible breeds of bovines. Sequencing of the gene coding for the heavy chain of IgG2 from 114 tick-resistant (Bos taurus indicus, Nelore breed) and tick-susceptible (B. t. taurus, Holstein breed) bovines revealed SNPs that generated 13 different haplotypes, of which 11 were novel and 5 were exclusive of Holstein and 3 of Nelore breeds. Alignment and modeling of coded haplotypes for hinge regions of the bovine IgG2 showed that they differ in the distribution of polar and hydrophobic amino acids and in shape according to the distribution of these amino acids. We also found that there was an association between genotypes of the constant region of the IgG2 heavy chain with phenotypes of tick infestations. These findings open the possibility of investigating if certain IgG allotypes hinder the function of tick IGBPs. If so, they may be markers for breeding for resistance against tick infestations.


Asunto(s)
Enfermedades de los Bovinos/genética , Bovinos/genética , Predisposición Genética a la Enfermedad , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas gamma de Inmunoglobulina/genética , Infestaciones por Garrapatas/veterinaria , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bovinos/inmunología , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/parasitología , Haplotipos , Masculino , Datos de Secuencia Molecular , Polimorfismo de Nucleótido Simple , Glándulas Salivales/inmunología , Infestaciones por Garrapatas/genética , Infestaciones por Garrapatas/inmunología , Garrapatas/inmunología
17.
Front Immunol ; 11: 1905, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33013839

RESUMEN

Bovine babesiosis is a tick-borne disease caused by intraerythrocytic protozoa and leads to substantial economic losses for the livestock industry throughout the world. Babesia bovis is considered the most pathogenic species, which causes bovine babesiosis in Brazil. Genomic data could be used to evaluate the viability of improving resistance against B. bovis infection level (IB) through genomic selection, and, for that, knowledge of genetic parameters is needed. Furthermore, genome-wide association studies (GWAS) could be conducted to provide a better understanding of the genetic basis of the host response to B. bovis infection. No previous work in quantitative genetics of B. bovis infection was found. Thus, the objective of this study was to estimate the genetic correlation between IB and tick count (TC), evaluate predictive ability and applicability of genomic selection, and perform GWAS in Hereford and Braford cattle. The single-step genomic best linear unbiased prediction method was used, which allows the estimation of both breeding values and marker effects. Standard phenotyping was conducted for both traits. IB quantifications from the blood of 1,858 animals were carried using quantitative PCR assays. For TC, one to three subsequent tick counts were performed by manually counting adult female ticks on one side of each animal's body that was naturally exposed to ticks. Animals were genotyped using the Illumina BovineSNP50 panel. The posterior mean of IB heritability, estimated by the Bayesian animal model in a bivariate analysis, was low (0.10), and the estimations of genetic correlation between IB and TC were also low (0.15). The cross-validation genomic prediction accuracy for IB ranged from 0.18 to 0.35 and from 0.29 to 0.32 using k-means and random clustering, respectively, suggesting that genomic predictions could be used as a tool to improve genetics for IB, especially if a larger training population is developed. The top 10 single nucleotide polymorphisms from the GWAS explained 5.04% of total genetic variance for IB, which were located on chromosomes 1, 2, 5, 6, 12, 17, 18, 16, 24, and 26. Some candidate genes participate in immunity system pathways indicating that those genes are involved in resistance to B. bovis in cattle. Although the genetic correlation between IB and TC was weak, some candidate genes for IB were also reported in tick infestation studies, and they were also involved in biological resistance processes. This study contributes to improving genetic knowledge regarding infection by B. bovis in cattle.


Asunto(s)
Vectores Artrópodos , Babesia bovis/patogenicidad , Babesiosis/genética , Babesiosis/parasitología , Bovinos/parasitología , Genómica , Polimorfismo de Nucleótido Simple , Garrapatas/parasitología , Animales , Babesia bovis/genética , Babesiosis/diagnóstico , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Herencia , Carga de Parásitos , Fenotipo , Carácter Cuantitativo Heredable , Índice de Severidad de la Enfermedad
18.
PLoS One ; 15(10): e0233941, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33108378

RESUMEN

We aimed to estimate the rate of germline mutations in the offspring of individuals accidentally exposed to Cesium-137 ionizing radiation. The study included two distinct groups: one of cases, consisting of males and females accidentally exposed to low doses of ionizing radiation of Cs137, and a control group of non-exposed participants. The cases included 37 people representing 11 families and 15 children conceived after the accident. Exposed families incurred radiation absorbed doses in the range of 0.2 to 0.5 Gray. The control group included 15 families and 15 children also conceived after 1987 in Goiânia with no history of radiation exposure. DNA samples from peripheral blood were analyzed with the Affymetrix GeneChip® CytoScanHD™ to estimate point mutations in autosomal SNPs. A set of scripts previously developed was used to detect de novo mutations by comparing parent and offspring genotypes at the level of each SNP marker. Overall numbers of observed Mendelian deviations were statistically significant between the exposed and control groups. Our retrospective transgenerational DNA analysis showed a 44.0% increase in the burden of SNP mutations in the offspring of cases when compared to controls, based on the average of MFMD for the two groups. Parent-of-origin and type of nucleotide substitution were also inferred. This proved useful in a retrospective estimation of the rate of de novo germline mutations in a human population accidentally exposed to low doses of radiation from Cesium-137. Our results suggested that observed burden of germline mutations identified in offspring was a potentially useful biomarker of effect to estimate parental exposure to low doses of IR and could become an important marker suitable for biomonitoring human population exposed to environmental mutagens.


Asunto(s)
Radioisótopos de Cesio/efectos adversos , Técnicas de Genotipaje/métodos , Mutación de Línea Germinal , Polimorfismo de Nucleótido Simple , Exposición a la Radiación/efectos adversos , Adolescente , Adulto , Sustitución de Aminoácidos , Estudios de Casos y Controles , Niño , Preescolar , Desastres , Femenino , Humanos , Lactante , Masculino , Análisis de la Aleatorización Mendeliana , Persona de Mediana Edad , Linaje , Radiación Ionizante , Liberación de Radiactividad Peligrosa , Estudios Retrospectivos , Adulto Joven
19.
Placenta ; 88: 52-60, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31671312

RESUMEN

INTRODUCTION: The expression of retroviral envelope proteins in the placenta facilitates generation of the multinuclear syncytiotrophoblast as an outer cellular layer of the placenta by fusion of the trophoblastic cells. This process is essential for placenta development in eutherians and for successful pregnancy. METHODS: We tested the hypothesis that alterations in DNA methylation and gene expression profiles of the endogenous retroviruses (ERVs) and genes related to epigenetic reprogramming in placenta of cloned calves result in abnormal offspring phenotypes. The fetal cotyledons in 13 somatic cell nuclear transfer (SCNT) pregnancies were collected. DNA methylation level of Fematrin-1 was analyzed using bisulfite PCR and mRNA levels of Fematrin-1, Syncytin-Rum1, DNMT1, DNMT3A, DNMT3B, TET1, TET2 and TET3 measured by RT-qPCR. RESULTS: Methylation of Fematrin-1 in placenta of control animals produced by artificial insemination (AI) was similar to live SCNT-produced calves, but hypermethylated than dead SCNT-produced calves. The levels of mRNA differed between SCNT-produced calves and AI animals for all genes, except TET3. However, no differences were observed between the live and dead cloned calves for all genes. Moreover, no differences were found between mRNA levels of Fematrin-1 and Syncytin-Rum1. DISCUSSION: Our results suggest that this altered DNA methylation, deregulation in the expression of ERVs and in the genes of epigenetic machinery in fetal cotyledons of cloned calves may be associated with abnormal placentogenesis found in SCNT-produced animals. Further studies characterizing other mechanisms involved in the regulation of ERVs are important to support the development of new strategies to improve the efficiency of cloning.


Asunto(s)
Metilación de ADN , Retrovirus Endógenos/metabolismo , Productos del Gen env/metabolismo , Técnicas de Transferencia Nuclear , Placentación , Proteínas Gestacionales/metabolismo , Animales , Bovinos , Clonación de Organismos , Retrovirus Endógenos/genética , Femenino , Productos del Gen env/genética , Placenta/virología , Embarazo , Proteínas Gestacionales/genética
20.
Epigenetics ; 14(6): 568-588, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30925851

RESUMEN

XIST, in association with the shorter ncRNA RepA, are essential for the initiation of X chromosome inactivation (XCI) in mice. The molecular mechanisms controlling XIST and RepA expression are well characterized in that specie. However, little is known in livestock. We aimed to characterize the DNA methylation status along the 5' portion of XIST and to characterize its transcriptional profile during early development in cattle. Three genomic regions of XIST named here as promoter, RepA and DMR1 had their DNA methylation status characterized in gametes and embryos. Expression profile of XIST was evaluated, including sense and antisense transcription. Oocytes showed higher levels of methylation than spermatozoa that was demethylated. DMR1 was hypermethylated throughout oogenesis. At the 8-16-cell embryo stage DMR1 was completed demethylated. Interestingly, RepA gain methylation during oocyte maturation and was demethylated at the blastocyst stage, later than DMR1. These results suggest that DMR1 and RepA are transient differentially methylated regions in cattle. XIST RNA was detected in matured oocytes and in single cells from the 2-cell to the morula stage, confirming the presence of maternal and embryonic transcripts. Sense and antisense transcripts were detected along the XIST in blastocyst. In silico analysis identified 63 novel transcript candidates at bovine XIST locus from both the plus and minus strands. Taking together these results improve our understanding of the molecular mechanisms involved in XCI initiation in cattle. This information may be useful for the improvement of assisted reproductive technologies in livestock considering that in vitro conditions may impair epigenetic reprogramming.


Asunto(s)
Biomarcadores/análisis , Metilación de ADN , Embrión de Mamíferos/metabolismo , Desarrollo Embrionario/genética , Regulación del Desarrollo de la Expresión Génica , Oogénesis/genética , ARN Largo no Codificante/genética , Animales , Bovinos , Embrión de Mamíferos/citología , Femenino , Células Germinativas/citología , Células Germinativas/metabolismo , Técnicas In Vitro , Oocitos/citología , Oocitos/metabolismo , Regiones Promotoras Genéticas , Análisis de la Célula Individual
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