Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.094
Filtrar
1.
BMC Plant Biol ; 19(1): 340, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31382873

RESUMO

BACKGROUND: Circular RNAs (circRNAs) are known to play an important role in the regulation of gene expression in eukaryotes. Photo-thermosensitive genic male sterile (PTGMS) is a very important germplasm resource in two-line hybrid rice breeding. Although many circRNAs have been identified in rice (Oryza sativa L.), little is known about the biological roles of circRNAs in the fertility transition of the PTGMS rice line. RESULTS: In the present study, RNA-sequencing libraries were constructed from the young panicles of the Wuxiang S sterile line rice (WXS (S)) and its fertile line rice (WXS (F)) at three development stages with three biological replicates. A total of 9994 circRNAs were obtained in WXS rice based on high-throughput strand-specific RNA sequencing and bioinformatic approaches, of which 5305 were known circRNAs and 4689 were novel in rice. And 14 of 16 randomly selected circRNAs were experimentally validated with divergent primers. Our results showed that 186 circRNAs were significantly differentially expressed in WXS (F) compared with WXS (S), of which 97, 87 and 60 circRNAs were differentially expressed at the pollen mother cell (PMC) formation stage (P2), the meiosis stage (P3) and the microspore formation stage (P4), respectively. Fertility specific expression patterns of eight circRNAs were analysis by qRT-PCR. Gene ontology (GO) and KEGG pathway analysis of the parental genes of differentially expressed circRNAs (DECs) revealed that they mainly participated in various biological processes such as development, response to stimulation, hormonal regulation, and reproduction. Furthermore, 15 DECs were found to act as putative miRNA sponges to involved in fertility transition in PTGMS rice line. CONCLUSION: In the present study, the abundance and characteristics of circRNAs were investigated in the PTGMS rice line using bioinformatic approaches. Moreover, the expression patterns of circRNAs were different between WXS (F) and WXS (S). Our findings primarily revealed that circRNAs might be endogenous noncoding regulators of flower and pollen development, and were involved in the fertility transition in the PTGMS rice line, and guide the production and application of two-line hybrid rice.


Assuntos
Oryza/genética , RNA/genética , Fertilidade/genética , Fertilidade/fisiologia , Flores/crescimento & desenvolvimento , Genes de Plantas/genética , Genes de Plantas/fisiologia , Resposta ao Choque Térmico , Sequenciamento de Nucleotídeos em Larga Escala , Oryza/fisiologia , Pólen/crescimento & desenvolvimento , RNA/fisiologia
2.
Yi Chuan ; 41(8): 703-715, 2019 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-31447421

RESUMO

Hybrid rice has contributed greatly to global food security. Cytoplasmic male sterility (CMS) and photo/ thermo sensitive genic male sterility (P/TGMS) are genetic bases for three-line and two-line hybrid rice production, respectively. In contrast, (sub-) specific hybrid sterility (HS) is a major barrier for utilization of hybrid vigor of distant hybrid rice. Therefore, understanding the molecular regulatory mechanism of rice fertility is a key technical issue for hybrid rice industry, and a long-standing basic scientific issue for nuclear-cytoplasmic interaction and reproductive isolation. Chinese geneticists of plant sciences have made tremendous contributions on the molecular genetic basis of rice fertility related to hybrid rice production. Here, we review the development of hybrid rice production systems in China and summarize current advance on genetic basis and molecular mechanism of CMS, P/TGMS, and HS involved in hybrid rice. We also discuss problems of hybrid rice production in China and point out new direction for future utilization of heterosis in rice.


Assuntos
Hibridização Genética , Oryza/genética , Oryza/fisiologia , Infertilidade das Plantas/genética , China , Fertilidade/genética , Vigor Híbrido
3.
Nat Commun ; 10(1): 3042, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31316054

RESUMO

Stress resistance and longevity are positively correlated but emerging evidence indicates that they are physiologically distinct. Identifying factors with distinctive roles in these processes is challenging because pro-longevity genes often enhance stress resistance. We demonstrate that TCER-1, the Caenorhabditis elegans homolog of human transcription elongation and splicing factor, TCERG1, has opposite effects on lifespan and stress resistance. We previously showed that tcer-1 promotes longevity in germline-less C. elegans and reproductive fitness in wild-type animals. Surprisingly, tcer-1 mutants exhibit exceptional resistance against multiple stressors, including infection by human opportunistic pathogens, whereas, TCER-1 overexpression confers immuno-susceptibility. TCER-1 inhibits immunity only during fertile stages of life. Elevating its levels ameliorates the fertility loss caused by infection, suggesting that TCER-1 represses immunity to augment fecundity. TCER-1 acts through repression of PMK-1 as well as PMK-1-independent factors critical for innate immunity. Our data establish key roles for TCER-1 in coordinating immunity, longevity and fertility, and reveal mechanisms that distinguish length of life from functional aspects of aging.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Regulação da Expressão Gênica/fisiologia , Imunidade Inata/genética , Longevidade/genética , Fatores de Alongamento de Peptídeos/metabolismo , Estresse Fisiológico/imunologia , Envelhecimento/genética , Envelhecimento/imunologia , Animais , Caenorhabditis elegans/fisiologia , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/imunologia , Suscetibilidade a Doenças/imunologia , Fertilidade/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Modelos Animais , Mutação , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/imunologia , Estresse Fisiológico/genética
4.
J Dairy Sci ; 102(9): 8184-8196, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31279556

RESUMO

Genetic evaluation of female fertility in Danish, Finnish, and Swedish dairy cows was updated in 2015 to multiple-trait animal model evaluation, where heifer and cow fertility up to third parity are considered as separate traits. A model for conception rate was also developed, which required variance component estimation for Nordic Holstein and Nordic Red Dairy Cattle. We used a multiple-trait multiple-lactation sire model to determine variance components for interval from calving to first insemination, length of service period, and conception rate. Monte Carlo Expectation Maximization REML allowed estimation of all 11 traits simultaneously. Study data were sampled from Swedish Holstein (n = 140,040) and Red Dairy Cattle (n = 101,315) heifers and cows. Conception rate observations are binomial observations with various numbers of failures preceding an observation of success. Using a simulation study, we confirmed that including a service number effect into the conception rate model allowed us to model the change in expectation of successful AI with increasing number of services. Heifers outperformed cows in all fertility traits according to the phenotypic means in the records. Heritabilities for the traits varied from 3 to 7% for interval from calving to first insemination, from 1 to 5% for length of service period, and from 1 to 3% for conception rate. Genetic correlations within traits (i.e., between parities) were favorable, ranging from moderate to high; genetic correlations between heifer and cow traits were lower than between cow traits in different parities. Lowest genetic correlations between traits were for interval from calving to first insemination and conception rate, intermediate for interval from calving to first insemination and length of service period, and highest for length of service period and conception rate. The variance components estimated in this study have been used in Nordic fertility breeding value evaluations since 2016.


Assuntos
Bovinos/genética , Fertilidade/genética , Paridade/genética , Animais , Cruzamento , Bovinos/fisiologia , Indústria de Laticínios , Feminino , Fertilização/genética , Lactação , Modelos Estatísticos , Gravidez
5.
J Dairy Sci ; 102(9): 8247-8250, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31255269

RESUMO

Phenotypes from the December 2018 US national genetic evaluations were used to compute effects of the polled haplotype in US Brown Swiss (BS), Holstein (HO), and Jersey (JE) cattle on milk, fat, and protein yields, somatic cell score, single-trait productive life, daughter pregnancy rate, heifer conception rate, and cow conception rate. Lactation records pre-adjusted for nongenetic factors and direct genomic values were used to estimate phenotypic and genetic effects of the polled haplotype, respectively. No phenotypic or direct genomic values effects were different from zero for any trait in any breed. Genomic PTA (gPTA) for the lifetime net merit (NM$) selection index of bulls born since January 1, 2012, that received a marketing code from the National Association of Animal Breeders (Madison, WI), and cows born on or after January 1, 2015, were compared to determine whether there was a systematic benefit to polled or horned genetics. Horned bulls had the highest average gPTA for NM$ in all 3 breeds, but that difference was significant only in HO and JE (HO: 615.4 ± 1.9, JE: 402.3 ± 3.4). Homozygous polled BS cows had significantly higher average gPTA for NM$ than their heterozygous polled or horned contemporaries (PP = 261.4 ± 43.5, Pp = 166.1 ± 13.7, pp = 174.1 ± 1.8), but the sample size was very small (n = 9). In HO and JE, horned cows had higher gPTA for NM$ (HO = 378.3 ± 0.2, JE = 283.3 ± 0.3). Selection for polled cattle should not have a detrimental effect on yield, fertility, or longevity, but these differences show that, in the short term, selection for polled over horned cattle will result in lower rates of genetic gain.


Assuntos
Bovinos/genética , Fertilidade/genética , Haplótipos/genética , Lactação/genética , Longevidade/genética , Fenótipo , Animais , Cruzamento/métodos , Bovinos/fisiologia , Contagem de Células , Feminino , Genômica , Genótipo , Haplótipos/fisiologia , Heterozigoto , Homozigoto , Masculino , Leite/química , Leite/citologia , Gravidez , Taxa de Gravidez , Seleção Genética
6.
J Dairy Sci ; 102(8): 7237-7247, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31155255

RESUMO

Relatedness between reference and test animals has an important effect on the reliability of genomic prediction for test animals. Because genomic prediction has been widely applied in practical cattle breeding and bulls have been selected according to genomic breeding value without progeny testing, the sires or grandsires of candidates might not have phenotypic information and might not be in the reference population when the candidates are selected. The objective of this study was to investigate the decreasing trend of the reliability of genomic prediction given distant reference populations, using genomic best linear unbiased prediction (GBLUP) and Bayesian variable selection models with or without including the quantitative trait locus (QTL) markers detected from sequencing data. The data used in this study consisted of 22,242 bulls genotyped using the 54K SNP array from EuroGenomics. Among them, 1,444 Danish bulls born from 2006 to 2010 were selected as test animals. Different reference populations with varying relationships to test animals were created according to pedigree-based relationships. The reference individuals having a relationship with one or more test animals higher than 0.4 (scenario ρ < 0.4), 0.2 (ρ < 0.2), or 0.1 (ρ < 0.1, where ρ = relationship coefficient) were removed from reference sets; these represented the distance between reference and test animals being 2 generations, 3 generations, and 4 generations, respectively. Imputed whole-genome sequencing data of bulls from Denmark were used to conduct a genome-wide association study (GWAS). A small number of significant variants (QTL markers) from the GWAS were added to the array data. To compare the effects of different models, the basic GBLUP model, a Bayesian selection variable model, a GBLUP model with 2 components of genetic effects, and a Bayesian model with pooled array data and QTL markers were used for estimating genomic estimated breeding values (GEBV) of test animals. The reliability of genomic prediction decreased when the test animals were more generations away from the reference population. The reliability of genomic prediction was 0.461 for 1 generation away and 0.396 for 3 generations away, with the same number of individuals in the reference set, using a GBLUP model with chip markers only. The results showed that using the Bayesian method and QTL markers improved the reliability of genomic prediction in all scenarios of relationship between test and reference animals, in a range of 1.3% and 65.1% (4 generations away with only 841 individuals in the reference set). However, most gains were for predictions of milk yield and fat yield. There was little improvement for predictions of protein yield and mastitis, and no improvement for prediction of fertility, except for scenario ρ < 0.1, in which there was a large improvement for predictions of all traits. On the other hand, models including more than 10% polygenic effect decreased prediction reliability when the relationship between test and reference animals was distant.


Assuntos
Teorema de Bayes , Bovinos/genética , Estudo de Associação Genômica Ampla/veterinária , Mastite Bovina/genética , Leite/metabolismo , Locos de Características Quantitativas/genética , Animais , Cruzamento , Dinamarca , Feminino , Fertilidade/genética , Marcadores Genéticos/genética , Genômica , Genótipo , Masculino , Herança Multifatorial/genética , Linhagem , Fenótipo , Reprodutibilidade dos Testes
7.
J Dairy Sci ; 102(8): 7226-7236, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31202648

RESUMO

The mammalian Y chromosome gene families in the ampliconic region are expressed predominantly or exclusively in the testis, and their copy number variations (CNV) are significantly associated with male reproductive traits, suggesting they have important roles in spermatogenesis and testicular development. ZNF280AY (zinc finger protein 280A, Y-linked) is a member of the zinc finger protein family and has been identified as a bovid-specific Y-chromosome gene. The current study applied a reliable quantitative real-time PCR method to estimate the CNV of ZNF280AY in 715 bulls across 21 cattle breeds and to further investigate the association of the CNV of ZNF280AY with bull reproductive traits and ZNF280AY mRNA expression levels in adult testis. The results revealed that the median copy number of ZNF280AY was 47, and the copy number varied from 11 to 154, showing significant CNV between and within the investigated cattle breeds. In addition, all 715 bulls were classified into Y1, Y2, and Y3 lineage groups based on a rapid genotyping method described previously. Pairwise comparisons indicated that bulls belonging to the Y1 lineage had a significantly lower median copy number (40) than bulls belonging to the Y2 (52) and Y3 lineages (57). Association analysis revealed that the CNV of ZNF280AY was correlated negatively with the percentage of normal sperm and sperm concentration in Holstein bulls, whereas no significant correlation was observed with ejaculation volume, total sperm count, sperm motility, postthaw motility (PTM), and scrotal circumference in Holstein and Simmental bulls. Furthermore, no correlation was observed between ZNF280AY copy number and ZNF280AY mRNA expression levels in the testis. The current study suggests that the CNV of the ZNF280AY gene family is associated with male reproductive traits and may serve as a valuable marker for early bull fertility selection in Holstein breeding programs.


Assuntos
Bovinos/genética , Variações do Número de Cópias de DNA , Fertilidade/genética , Regulação da Expressão Gênica , Genes Ligados ao Cromossomo Y/genética , Reprodução/genética , Cromossomo Y/genética , Animais , Cruzamento , Bovinos/fisiologia , Marcadores Genéticos/genética , Genótipo , Masculino , Especificidade de Órgãos , Fenótipo , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Especificidade da Espécie , Contagem de Espermatozoides/veterinária , Motilidade Espermática/genética , Espermatogênese/genética , Testículo/fisiologia , Dedos de Zinco/genética
8.
Bull Environ Contam Toxicol ; 103(2): 233-239, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31230133

RESUMO

We aimed to identify genetic variation in the response of reproductive behaviors to lead (Pb2+) exposure. We reared a subset of the Drosophila Genetic Reference Panel (DGRP) inbred lines on control or Pb-treated (500 µM PbAc) medium and tested for differences in copulation latency, copulation duration, and fecundity. Pb exposure decreased fecundity (p < 0.05) and increased copulation duration (p < 0.05) across DGRP lines. We found intraspecific genetic variation in latency, duration, and fecundity in both control and Pb-treated flies, with heritability ranging from 0.45 to 0.80. We found a significant genotype-by-environment interaction for copulation duration (p < 0.05). Genetic correlation matrices revealed significant genetic variation in common between control and Pb-treated flies for each trait (p < 0.05). Our results indicate that intraspecific genetic variation plays a role in Pb susceptibility and emphasize the importance of considering the impacts of variation in susceptibility to Pb pollution.


Assuntos
Copulação/efeitos dos fármacos , Drosophila melanogaster/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Variação Genética , Chumbo/toxicidade , Animais , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Fertilidade/efeitos dos fármacos , Fertilidade/genética , Fenótipo
9.
J Dairy Sci ; 102(9): 8134-8147, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31229284

RESUMO

Conventional and organic production systems mainly differ in feeding strategies, outdoor and pasture access, and the use of antibiotic treatments. These environmental differences could lead to a genotype by environment interaction (G × E) and a requirement for including G × E in breeding decisions. The objectives of this study were to estimate variance components and heritabilities for conventional and organic production systems and investigate G × E under these 2 production systems for female fertility traits in Danish Holsteins. The analyzed traits included the interval from calving to first insemination (ICF), the interval from first to last insemination, number of inseminations per conception (NINS), and non-return rate within 56 d after the first insemination. Records of female fertility in heifers and the first 3 lactations in cows as well as grass ratio of feed at herd level were collected during the period from 2011 to 2016. The performances of a trait in heifers and cows (lactation 1 to 3) were considered as different traits. The (co)variance components and the resulting heritabilities and genetic correlations were estimated using 2 models. One was a bivariate model treating performances of a trait under organic and conventional production systems as 2 different traits using a reduced data set, and the other was a reaction norm model with random regression on the production system and the grass ratio of feed using a full data set. The full data set comprised records of 37,836 females from 112 organic herds and 513,599 females from 1,224 conventional herds, whereas the reduced data set comprised records from all these 112 organic herds and 92,696 females from 185 convention herds extracted from the full data set with grass ratio of feed lower than 0.20. All female fertility performances of the organic production system were superior to those of the conventional production system. Besides, heterogeneities in additive genetic variances and heritabilities were observed between conventional and organic production systems for all traits. Furthermore, genetic correlations between these 2 production systems ranged from 0.607 to 1.000 estimated from bivariate models and from 0.848 to 0.999 estimated from reaction norm models. Statistically significant G × E were observed for NINS in heifers, non-return rate within 56 d after the first insemination in heifers, and ICF from the bivariate model, and for ICF and NINS in cows from the reaction norm model.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Fertilidade/genética , Interação Gene-Ambiente , Animais , Cruzamento , Bovinos/genética , Feminino , Fertilização , Genótipo , Inseminação , Lactação , Agricultura Orgânica , Fenótipo , Poaceae
10.
Cell Mol Life Sci ; 76(20): 4071-4102, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31254043

RESUMO

Mammalian spermatogenesis is a highly complex multi-step process sustained by a population of mitotic germ cells with self-renewal potential known as spermatogonial stem cells (SSCs). The maintenance and regulation of SSC function are strictly dependent on a supportive niche that is composed of multiple cell types. A detailed appreciation of the molecular mechanisms underpinning SSC activity and fate is of fundamental importance for spermatogenesis and male fertility. However, different models of SSC identity and spermatogonial hierarchy have been proposed and recent studies indicate that cell populations supporting steady-state germline maintenance and regeneration following damage are distinct. Importantly, dynamic changes in niche properties may underlie the fate plasticity of spermatogonia evident during testis regeneration. While formation of spermatogenic colonies in germ-cell-depleted testis upon transplantation is a standard assay for SSCs, differentiation-primed spermatogonial fractions have transplantation potential and this assay provides readout of regenerative rather than steady-state stem cell capacity. The characterisation of spermatogonial populations with regenerative capacity is essential for the development of clinical applications aimed at restoring fertility in individuals following germline depletion by genotoxic treatments. This review will discuss regulatory mechanisms of SSCs in homeostatic and regenerative testis and the conservation of these mechanisms between rodent models and man.


Assuntos
Fertilidade/genética , Infertilidade Masculina/genética , Espermatogênese/genética , Espermatogônias/citologia , Células-Tronco/citologia , Testículo/citologia , Animais , Diferenciação Celular , Regulação da Expressão Gênica , Homeostase/genética , Humanos , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Infertilidade Masculina/terapia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Modelos Genéticos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Espermatogônias/metabolismo , Nicho de Células-Tronco/genética , Células-Tronco/metabolismo , Testículo/metabolismo
11.
J Dairy Sci ; 102(9): 8210-8220, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31229287

RESUMO

This study investigated the effects of alternative mating programs that incorporate genomic information on expected progeny herd performance and inbreeding, as well as methods to include un-genotyped animals in such mating programs. A total of 54,535 Holstein-Friesian cattle with imputed high-density genotypes (547,650 SNP after edits) were available. First, to quantify the accuracy of imputing un-genotyped animals (often an issue in populations), a sub-population of 729 genotyped animals had their genotypes masked, and their allele dosages were imputed, using linear regression exploiting information on genotyped relatives. The reference population for imputation included all genotyped animals, excluding the 729 selected animals and their sires, dams, and grandsires, and had either (1) their sires' genotypes, (2) their dams' genotypes (3) both their sires' and their dams' genotypes, or (4) both their sires' and maternal grandsires' genotypes introduced into the reference population. The correlations between true genotypes and the imputed allele dosages ranged from 0.58 (sire only) to 0.68 (both sire and dam). A herd of 100 cows was then simulated (1,000 replicates) from the sub-population of 729 imputed animals. The top 10 bulls from the genotyped population, based on their total genetic merit index (TMI) were selected to be used as sires. Three mating allotment methods were investigated: (1) random mating, (2) sequential mating based on maximizing only the expected TMI of the progeny, and (3) linear programming to maximize a generated index constructed to maximize genetic merit and minimize expected progeny inbreeding as well as intra- and inter-progeny variability in genetic merit. Relationships among candidate parents were calculated using either the pedigree relationship matrix or the genomic relationship matrix; the latter was constructed using either the true genotypes of both parents or the true genotypes of the sire plus the imputed allele dosages of the dam. Using the genomic co-ancestry estimates resulted in lower average herd expected genomic inbreeding levels compared with using the pedigree-based co-ancestry estimates. Additionally, if the dams were not genotyped, using their imputed allele dosages also resulted in lower average herd expected inbreeding levels compared with using the pedigree co-ancestry estimates. The inter-progeny coefficient of variation for selected traits, milk and fertility, estimated breeding values were reduced by 12 to 65% using the linear programing method compared with sequential mating.


Assuntos
Cruzamento/métodos , Bovinos/genética , Genômica , Genótipo , Algoritmos , Animais , Feminino , Fertilidade/genética , Frequência do Gene , Endogamia , Lactação/genética , Masculino , Linhagem , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas/genética , Característica Quantitativa Herdável
12.
Mol Cell ; 74(5): 982-995.e6, 2019 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-31076285

RESUMO

PIWI-interacting RNAs (piRNAs) silence transposons in Drosophila ovaries, ensuring female fertility. Two coupled pathways generate germline piRNAs: the ping-pong cycle, in which the PIWI proteins Aubergine and Ago3 increase the abundance of pre-existing piRNAs, and the phased piRNA pathway, which generates strings of tail-to-head piRNAs, one after another. Proteins acting in the ping-pong cycle localize to nuage, whereas phased piRNA production requires Zucchini, an endonuclease on the mitochondrial surface. Here, we report that Armitage (Armi), an RNA-binding ATPase localized to both nuage and mitochondria, links the ping-pong cycle to the phased piRNA pathway. Mutations that block phased piRNA production deplete Armi from nuage. Armi ATPase mutants cannot support phased piRNA production and inappropriately bind mRNA instead of piRNA precursors. We propose that Armi shuttles between nuage and mitochondria, feeding precursor piRNAs generated by Ago3 cleavage into the Zucchini-dependent production of Aubergine- and Piwi-bound piRNAs on the mitochondrial surface.


Assuntos
Proteínas Argonauta/genética , Proteínas de Drosophila/genética , Mitocôndrias/genética , Fatores de Iniciação de Peptídeos/genética , RNA Helicases/genética , RNA Interferente Pequeno/genética , Animais , Drosophila melanogaster/genética , Endorribonucleases/genética , Feminino , Fertilidade/genética , Células Germinativas/metabolismo , Mitocôndrias/metabolismo , Mutação , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Proteínas de Ligação a RNA/genética
13.
Nat Commun ; 10(1): 2278, 2019 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-31123254

RESUMO

Mammalian spermatogenesis is sustained by mitotic germ cells with self-renewal potential known as undifferentiated spermatogonia. Maintenance of undifferentiated spermatogonia and spermatogenesis is dependent on tightly co-ordinated transcriptional and post-transcriptional mechanisms. The RNA helicase DDX5 is expressed by spermatogonia but roles in spermatogenesis are unexplored. Using an inducible knockout mouse model, we characterise an essential role for DDX5 in spermatogonial maintenance and show that Ddx5 is indispensable for male fertility. We demonstrate that DDX5 regulates appropriate splicing of key genes necessary for spermatogenesis. Moreover, DDX5 regulates expression of cell cycle genes in undifferentiated spermatogonia post-transcriptionally and is required for cell proliferation and survival. DDX5 can also act as a transcriptional co-activator and we demonstrate that DDX5 interacts with PLZF, a transcription factor required for germline maintenance, to co-regulate select target genes. Combined, our data reveal a critical multifunctional role for DDX5 in regulating gene expression programmes and activity of undifferentiated spermatogonia.


Assuntos
RNA Helicases DEAD-box/metabolismo , Proteína com Dedos de Zinco da Leucemia Promielocítica/metabolismo , Processamento de RNA/fisiologia , Espermatogênese/genética , Espermatogônias/metabolismo , Animais , Ciclo Celular/genética , Proliferação de Células/genética , Técnicas de Cocultura , RNA Helicases DEAD-box/genética , Embrião de Mamíferos , Fertilidade/genética , Fibroblastos , Regulação da Expressão Gênica/fisiologia , Masculino , Camundongos , Camundongos Knockout , Modelos Animais , Cultura Primária de Células , Testículo/citologia
14.
J Dairy Sci ; 102(6): 5330-5341, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30954255

RESUMO

Our aim was to map the performance of local (native) dairy cattle breeds in Austria, Switzerland, Poland, and Sweden with regard to production, fertility, longevity, and health-associated traits and to compare them with commercial (modern) breeds. For this purpose, we analyzed test-day records (July 1, 2011, to June 30, 2014) and treatment records (Austria, Sweden) of cows managed on organic farms. We performed country-wise comparisons of 123,415 lactations from Original Braunvieh (OB) and Grey Cattle (AL) with Braunvieh (BV; Brown Swiss blood >60%) in Switzerland; AL with BV (Brown Swiss blood >50%) in Austria; Polish Black and White (ZB), Polish Red and White (ZR), and Polish Red (RP) with Polish Holstein Friesian (PHF) in Poland; and Swedish Red (SRB) with Swedish Holstein (SH) in Sweden. Average milk yields were substantially lower for local compared with commercial breeds in all countries; differences ranged from 750 kg (Sweden) to 1,822 kg (Austria), albeit on very different average levels. Local breeds showed a longer productive lifetime by 0.64, 0.83, 1.42, and 0.20 lactations in Switzerland, Austria, Poland, and Sweden, respectively, again on very different levels in each country. Regarding fertility traits, calving interval was shorter in local than in commercial breeds by 13 (Sweden), 14 (Switzerland), and 20 d (Austria, Poland). Insemination index was lower in certain local breeds by 0.15 (Switzerland), 0.14 (Austria), 0.21 (Poland), and 0.13 (Sweden). Several local breeds showed a lower proportion of cows with >100,000 somatic cells/mL. This was the case in Switzerland (OB 24.2%; BV 35.8%), Austria (AL 25.3%; BV 36.9%), and Sweden (SRB 42.4%; SH 43.4%). In contrast, the respective proportion in Poland exceeded 82% in all breeds except the commercial PHF (76.1%). In Sweden, lactations with veterinary treatments were considerably less prevalent in SRB (15.6%) than in SH (21.7%). In Austria, breeds differed only in treatments for udder disorders, which favored AL. In conclusion, the markedly lower milk yields of local breeds are partly counterbalanced by (somewhat inconsistent) advantages in longevity, fertility, and health traits across 4 European countries. This indicates that the robustness of local breeds can contribute to improved sustainability of organic dairy systems.


Assuntos
Criação de Animais Domésticos/métodos , Bovinos/genética , Fertilidade/genética , Lactação/genética , Animais , Áustria , Cruzamento , Indústria de Laticínios , Feminino , Longevidade , Agricultura Orgânica , Polônia , Suécia , Suíça
15.
BMC Genomics ; 20(1): 291, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30987590

RESUMO

BACKGROUND: Identifying causative mutations or genes through which quantitative trait loci (QTL) act has proven very difficult. Using information such as gene expression may help to identify genes and mutations underlying QTL. Our objective was to identify regions associated both with production traits or fertility and with gene expression, in dairy cattle. We used three different approaches to discover QTL that are also expression QTL (eQTL): 1) estimate the correlation between local genomic estimated breeding values (GEBV) and gene expression, 2) investigate whether the 300 intervals explaining most genetic variance for a trait contain more eQTL than 300 randomly selected intervals, and 3) a colocalisation analysis. Phenotypes and genotypes up to sequence level of 35,775 dairy bulls and cows were used for QTL mapping, and gene expression and genotypes of 131 cows were used to identify eQTL. RESULTS: With all three approaches, we identified some overlap between eQTL and QTL, though the majority of QTL in our dataset did not seem to be eQTL. The most significant associations between QTL and eQTL were found for intervals on chromosome 18, where local GEBV for all traits showed a strong association with the expression of the FUK and DDX19B. Intervals whose local GEBV for a trait correlated highly significantly with the expression of a nearby gene explained only a very small part of the genetic variance for that trait. It is likely that part of these correlations were due to linkage disequilibrium (LD) in the interval. While the 300 intervals explaining most genetic variance explained most of the GEBV variance, they contained only slightly more eQTL than 300 randomly selected intervals that explained a minimal portion of the GEBV variance. Furthermore, some variants showed a high colocalisation probability, but this was only the case for few variants. CONCLUSIONS: Several reasons may have contributed to the low level of overlap between QTL and eQTL detected in our study, including a lack of power in the eQTL study and long-range LD making it difficult to separate QTL and eQTL. Furthermore, it may be that eQTL explain only a small fraction of QTL.


Assuntos
Bovinos/genética , Bovinos/fisiologia , Indústria de Laticínios , Fertilidade/genética , Locos de Características Quantitativas/genética , Animais , Bovinos/metabolismo , Variação Genética , Estudo de Associação Genômica Ampla
16.
J Dairy Sci ; 102(6): 5295-5304, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30981479

RESUMO

Sustainable dairy cow performance relies on coevolution in the development of breeding and management strategies. Tailoring breeding programs to herd performance metrics facilitates improved responses to breeding decisions. Although herd-level raw metrics on performance are useful, implicitly included within such statistics is the mean herd genetic merit. The objective of the present study was to quantify the expected response from selection decisions on additive and nonadditive merit by herd performance metrics independent of herd mean genetic merit. Performance traits considered in the present study were age at first calving, milk yield, calving to first service, number of services, calving interval, and survival. Herd-level best linear unbiased estimates (BLUE) for each performance trait were available on a maximum of 1,059 herds, stratified as best, average, and worst for each performance trait separately. The analyses performed included (1) the estimation of (co)variance for each trait in the 3 BLUE environments and (2) the regression of cow-level phenotypic performance on either the respective estimated breeding value (EBV) or the heterosis coefficient of the cow. A fundamental assumption of genetic evaluations is that 1 unit change in EBV equates to a 1 unit change in the respective phenotype; results from the present study, however, suggest that the realization of the change in phenotypic performance is largely dependent on the herd BLUE for that trait. Herds achieving more yield, on average, than expected from their mean genetic merit, had a 20% greater response to changes in EBV as well as 43% greater genetic standard deviation relative to herds within the worst BLUE for milk yield. Conversely, phenotypic performance in fertility traits (with the exception of calving to first service) tended to have a greater response to selection as well as a greater additive genetic standard deviation within the respective worst herd BLUE environments; this is suggested to be due to animals performing under more challenging environments leading to larger achievable gains. The attempts to exploit nonadditive genetic effects such as heterosis are often the basis of promoting cross-breeding, yet the results from the present study suggest that improvements in phenotypic performance is largely dependent on the environment. The largest gains due to heterotic effects tended to be within the most stressful (i.e., worst) BLUE environment for all traits, thus suggesting the heterosis effects can be beneficial in mitigating against poorer environments.


Assuntos
Cruzamento , Bovinos/genética , Lactação/genética , Envelhecimento , Criação de Animais Domésticos , Animais , Feminino , Fertilidade/genética , Leite , Parto/genética , Gravidez , Seleção Genética
17.
Genet Sel Evol ; 51(1): 15, 2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-30999842

RESUMO

BACKGROUND: Quantitative genetic studies suggest the existence of variation at the genome level that affects the ability of cattle to resist to parasitic diseases. The objective of the current study was to identify regions of the bovine genome that are associated with resistance to endo-parasites. METHODS: Individual cattle records were available for Fasciola hepatica-damaged liver from 18 abattoirs. Deregressed estimated breeding values (EBV) for F. hepatica-damaged liver were generated for genotyped animals with a record for F. hepatica-damaged liver and for genotyped sires with a least one progeny record for F. hepatica-damaged liver; 3702 animals were available. In addition, individual cow records for antibody response to F. hepatica on 6388 genotyped dairy cows, antibody response to Ostertagia ostertagi on 8334 genotyped dairy cows and antibody response to Neospora caninum on 4597 genotyped dairy cows were adjusted for non-genetic effects. Genotypes were imputed to whole-sequence; after edits, 14,190,141 single nucleotide polymorphisms (SNPs) and 16,603,644 SNPs were available for cattle with deregressed EBV for F. hepatica-damaged liver and cows with an antibody response to a parasitic disease, respectively. Association analyses were undertaken using linear regression on one SNP at a time, in which a genomic relationship matrix accounted for the relationships between animals. RESULTS: Genomic regions for F. hepatica-damaged liver were located on Bos taurus autosomes (BTA) 1, 8, 11, 16, 17 and 18; each region included at least one SNP with a p value lower than 10-6. Five SNPs were identified as significant (q value < 0.05) for antibody response to N. caninum and were located on BTA21 or 25. For antibody response to F. hepatica and O. ostertagi, six and nine quantitative trait loci (QTL) regions that included at least one SNP with a p value lower than 10-6 were identified, respectively. Gene set enrichment analysis revealed a significant association between functional annotations related to the olfactory system and QTL that were suggestively associated with endo-parasite phenotypes. CONCLUSIONS: A number of novel genomic regions were suggestively associated with endo-parasite phenotypes across the bovine genome and two genomic regions on BTA21 and 25 were associated with antibody response to N. caninum.


Assuntos
Doenças dos Bovinos/genética , Bovinos/genética , Interações Hospedeiro-Parasita/genética , Animais , Cruzamento , Fasciola hepatica/patogenicidade , Fertilidade/genética , Variação Genética/genética , Estudo de Associação Genômica Ampla/veterinária , Genótipo , Parasitos/genética , Parasitos/patogenicidade , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Sequenciamento Completo do Genoma/métodos
18.
Anim Sci J ; 90(6): 719-727, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30983045

RESUMO

Apoptosis of granulosa cells affects follicular atresia and reproduction and is regulated by miRNAs and the expression of certain genes. For the present study, we investigated the regulatory relationship between microRNA-222 (miR-222) and THBS1 in porcine follicular granulosa cells (pGCs) and its effects on apoptosis to provide empirical data for developing methods to improve pig fecundity. Results revealed that miR-222 promotes the proliferation of pGCs. MiRNA mimics and luciferase reporter assays revealed that miR-222 functions as an anti-apoptotic factor in pGCs. MiR-222 mimics in pGCs result in the upregulation of the anti-apoptotic BCL-2 gene, down-regulation of the proapoptotic caspase-3 gene, and inhibition of apoptosis. MiR-222 inhibitors reduced BCL-2 and had no significant effect on caspase-3. MiR-222 mimics promoted estrogen levels. Inhibition of THBS1 inhibited pGC apoptosis. Transfection of THBS1-siRNA reduced the proapoptotic BAX gene. MiR-222 can directly target the 3'-untranslated region of the THBS1 gene. MiR-222 mimics suppressed THBS1 mRNA and proteins, but these were upregulated by the miR-222 inhibitor. Transfection of THBS1-siRNA resulted in the inhibition of the miR-222 inhibitor, which suggests that miR-222 inhibits pGC apoptosis by targeting THBS1. These findings suggest that miR-222 and THBS1 play important roles in follicular atresia, ovarian development, and female reproduction.


Assuntos
Apoptose/genética , Células da Granulosa/patologia , MicroRNAs/fisiologia , Folículo Ovariano/citologia , Trombospondinas/fisiologia , Animais , Caspase 3 , Proliferação de Células/genética , Células Cultivadas , Feminino , Fertilidade/genética , Genes bcl-2 , MicroRNAs/genética , Reprodução/genética , Suínos , Trombospondinas/genética
19.
BMC Genomics ; 20(1): 255, 2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30935378

RESUMO

BACKGROUND: An unfavorable genetic correlation between milk production and fertility makes simultaneous improvement of milk production and fertility difficult in cattle breeding. Rapid genetic improvement in milk production traits in dairy cattle has been accompanied by decline in cow fertility. The genetic basis of this correlation remains poorly understood. Expanded reference populations and large sets of sequenced animals make genome-wide association studies (GWAS) with imputed markers possible for large populations and thereby studying genetic architecture of complex traits. RESULTS: In this study, we associated 15,551,021 SNPs with female fertility index in 5038 Nordic Holstein cattle. We have identified seven quantitative trait loci (QTL) on six chromosomes in cattle. Along with nearest genes to GWAS hits, we used gene-based analysis and spread of linkage disequilibrium (LD) information to generate a list of potential candidate genes affecting fertility in cattle. Subsequently, we used prior knowledge on gene related to fertility from Gene Ontology terms, Kyoto Encyclopedia of Genes and Genomes pathway analysis, mammalian phenotype database, and public available RNA-seq data to refine the list of candidate genes for fertility. We used variant annotations to investigate candidate mutations within the prioritized candidate genes. Using multiple source of information, we proposed candidate genes with biological relevance underlying each of these seven QTL. On chromosome 1, we have identified ten candidate genes for two QTL. For the rest of chromosomes, we proposed one candidate gene for each QTL. In the candidate genes list, differentially expressed genes from different studies support FRAS1, ITGB5, ADCY5, and SEMA5B as candidate genes for cow fertility. CONCLUSION: The GWAS result not only confirmed previously mapped QTL, but also made new findings. Our findings contributes towards dissecting the genetics for female fertility in cattle. Moreover, this study shows the usefulness of adding independent information to pick candidate genes during post-GWAS analysis.


Assuntos
Fertilidade/genética , Adenilil Ciclases/genética , Animais , Bovinos , Proteínas da Matriz Extracelular/genética , Feminino , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Genótipo , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Semaforinas/genética
20.
BMC Genomics ; 20(1): 258, 2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30940077

RESUMO

BACKGROUND: Fertility is among the most important economic traits in dairy cattle. Genomic prediction for cow fertility has received much attention in the last decade, while bull fertility has been largely overlooked. The goal of this study was to assess genomic prediction of dairy bull fertility using markers with large effect and functional annotation data. Sire conception rate (SCR) was used as a measure of service sire fertility. Dataset consisted of 11.5 k U.S. Holstein bulls with SCR records and about 300 k single nucleotide polymorphism (SNP) markers. The analyses included the use of both single-kernel and multi-kernel predictive models fitting either all SNPs, markers with large effect, or markers with presumed functional roles, such as non-synonymous, synonymous, or non-coding regulatory variants. RESULTS: The entire set of SNPs yielded predictive correlations of 0.340. Five markers located on chromosomes BTA8, BTA9, BTA13, BTA17, and BTA27 showed marked dominance effects. Interestingly, the inclusion of these five major markers as fixed effects in the predictive models increased predictive correlations to 0.403, representing an increase in accuracy of about 19% compared with the standard model. Single-kernel models fitting functional SNP classes outperformed their counterparts using random sets of SNPs, suggesting that the predictive power of these functional variants is driven in part by their biological roles. Multi-kernel models fitting all the functional SNP classes together with the five major markers exhibited predictive correlations around 0.405. CONCLUSIONS: The inclusion of markers with large effect markedly improved the prediction of dairy sire fertility. Functional variants exhibited higher predictive ability than random variants, but did not outperform the standard whole-genome approach. This research is the foundation for the development of novel strategies that could help the dairy industry make accurate genome-guided selection decisions on service sire fertility.


Assuntos
Fertilidade/genética , Modelos Genéticos , Animais , Biomarcadores/metabolismo , Bovinos , Genótipo , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA