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1.
J Insect Sci ; 20(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32092133

RESUMO

Mating promotes reproductive activity, which may impact immune performance. Paradoxically, mating frequently challenges females' immunity (e.g., infections). Therefore, studies of postmating resource allocation between reproduction and survival are likely to shed new light on life-history trade-off and sexual selection. Here, we used RNAseq to test whether and how mating affected mRNA expression in genes related to reproduction and immunity in Spodoptera litura female moths. Results show a divergent change in the differentially expressed genes (DEGs) between reproduction and immunity: the immune response was largely downregulated shortly after mating (~6 h postmating), which has some recovery at 24 h postmating; reproductive response is trivial shortly after mating (~6 h postmating), but it largely upregulated at 24 h postmating (e.g., egg maturation related genes were highly upregulated). Considering the fact that most of the total DEGs downregulated from 0 to 6 h postmating (from 51/68 to 214/260) but most of the total DEGs upregulated at 24 h postmating (816/928), it is possible that trade-offs between reproduction and immunity occurred in mated females. For example, they may shut down immunity to favor sperm storage and save limited resources to support the increased energy required in reproduction (e.g., egg maturation and oviposition). Mating-induced infections should be trivial due to low polyandry in S. litura. A reduced immune defense may have no threat to S. litura survival but may benefit reproduction significantly. Furthermore, obvious expression changes were detected in genes related to hormone production, suggesting that endocrine changes could play important roles in postmating responses.


Assuntos
Copulação , Spodoptera/genética , Spodoptera/imunologia , Animais , Feminino , Expressão Gênica/fisiologia , Masculino , RNA Mensageiro , Reprodução/genética , Spodoptera/metabolismo
2.
Insect Biochem Mol Biol ; 116: 103243, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31541694

RESUMO

Sterile insect technology (SIT) is an environmentally friendly method for pest control. As part of our efforts to develop a strategy that results in engineered male-sterile strains with minimum effects on viability and mating competition, we used CRISPR/Cas9 technology to disrupt Ser2, which encodes a seminal fluid protein, in the model lepidopteran insect, Bombyx mori, and an important agricultural pest, Plutella xylostella. Disruption of Ser2 resulted in dominant heritable male sterility. Wild-type females mated with Ser2-deficient males laid eggs normally, but the eggs did not hatch. We detected no differences in other reproductive behaviors in the mutant males. These results support the conclusion that Ser2 gene is necessary for male reproductive success in diverse lepidopterans. Targeting Ser2 gene has the potential to form the basis for a new strategy for pest control.


Assuntos
Proteínas de Insetos/genética , Mariposas/fisiologia , Serina Proteases/genética , Animais , Bombyx/genética , Bombyx/fisiologia , Sistemas CRISPR-Cas , Infertilidade Masculina/genética , Proteínas de Insetos/metabolismo , Masculino , Mariposas/genética , Mutação , Reprodução/genética , Serina Proteases/metabolismo
3.
J Dairy Sci ; 103(1): 1016-1030, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31759601

RESUMO

The objective of this study was to evaluate associations between corpus luteum (CL) status, uterine health, body condition score (BCS), metabolic status, parity, genetic merit for fertility traits, and reproductive performance in pasture-based dairy cows managed for seasonal reproduction. First- and second-lactation (n = 2,600) spring-calving dairy cows from 35 dairy farms located in Ireland were enrolled in the study. Farms were visited every 2 wk, and animals that were at wk 3 (range: 14-27 d in milk) and wk 7 (range: 42-55 d in milk) postpartum were examined. Body condition score was measured using a 1-to-5 scale in 0.25-point increments. Transrectal ultrasound examination was performed at wk 3 and 7 postpartum to determine presence or absence of CL and ultrasound reproductive tract score (scale of G1-G4). Blood samples were collected at each visit, and the concentrations of glucose, ß-hydroxybutyrate (BHB), and fatty acids (FA) were analyzed using enzymatic colorimetry. Animals were grouped into 3 BCS categories [low (≤2.5), target (2.75-3.25), and high (≥3.5)], 2 CL categories (present or absent), 2 uterine health status categories (normal or abnormal), and 3 metabolic status categories [good (high glucose, low FA and BHB), poor (low glucose, high FA and BHB), and moderate (all other combinations)]. Fisher's exact test was used to test for associations between variables and was supplemented by logistic regression. More cows with a CL at wk 7 were served during the first 21 d of the breeding period compared with cows without a CL. Cows classified as having a uterine score of G3 or G4 at wk 3 and 7 had lower odds of pregnancy establishment during the breeding period compared with animals with a uterine score of G1 or G2. Animals with low BCS at wk 7 had lower odds of pregnancy establishment than cows with a target BCS. Cows classified as having good metabolic status at both wk 3 and wk 7 had greater odds of pregnancy establishment during the first 21 d of the breeding season than those classified as having poor metabolic status. Overall, primiparous cows had greater reproductive performance than second-parity cows. Animals in the quartiles with the best predicted transmitting ability for survival and calving interval had better reproductive performance compared with animals in the other quartiles. Cows that had better genetic merit for fertility traits and good metabolic status, achieved target BCS, and had a favorable ultrasound reproductive tract score and a CL present at wk 7 postpartum had superior reproductive performance.


Assuntos
Bovinos/genética , Lactação/genética , Período Pós-Parto , Criação de Animais Domésticos , Animais , Bovinos/fisiologia , Suplementos Nutricionais , Feminino , Fertilidade/genética , Irlanda , Lactação/fisiologia , Leite/metabolismo , Gravidez , Reprodução/genética , Estações do Ano
4.
PLoS Biol ; 17(11): e3000493, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31689300

RESUMO

Changing environmental conditions cause changes in the distributions of phenotypic traits in natural populations. However, determining the mechanisms responsible for these changes-and, in particular, the relative contributions of phenotypic plasticity versus evolutionary responses-is difficult. To our knowledge, no study has yet reported evidence that evolutionary change underlies the most widely reported phenotypic response to climate change: the advancement of breeding times. In a wild population of red deer, average parturition date has advanced by nearly 2 weeks in 4 decades. Here, we quantify the contribution of plastic, demographic, and genetic components to this change. In particular, we quantify the role of direct phenotypic plasticity in response to increasing temperatures and the role of changes in the population structure. Importantly, we show that adaptive evolution likely played a role in the shift towards earlier parturition dates. The observed rate of evolution was consistent with a response to selection and was less likely to be due to genetic drift. Our study provides a rare example of observed rates of genetic change being consistent with theoretical predictions, although the consistency would not have been detected with a solely phenotypic analysis. It also provides, to our knowledge, the first evidence of both evolution and phenotypic plasticity contributing to advances in phenology in a changing climate.


Assuntos
Cervos/fisiologia , Parto/genética , Parto/metabolismo , Adaptação Fisiológica/genética , Adaptação Fisiológica/fisiologia , Animais , Evolução Biológica , Cruzamento , Mudança Climática , Fenótipo , Reprodução/genética , Reprodução/fisiologia , Escócia , Estações do Ano , Seleção Genética/fisiologia
5.
Curr Med Sci ; 39(5): 679-684, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31612382

RESUMO

Diet has been shown to play an important role in human physiology. It is a predominant exogenous factor regulating the composition of gut microbiota, and dietary intervention holds promise for treatment of diseases such as obesity, type 2 diabetes, and malnutrition. Furthermore, it was reported that diet has significant effects on physiological processes of C. elegans, including reproduction, fat storage, and aging. To reveal novel signaling pathways responsive to different diets, C. elegans and its bacterial diet were used as an interspecies model system to mimic the interaction between host and gut microbiota. Most signaling pathways identified in C. elegans are highly conserved across different species, including humans. A better understanding of these pathways can, therefore, help to develop interventions for human diseases. In this article, we summarize recent achievements on molecular mechanisms underlying the response of C. elegans to different diets and discuss their relevance to human health.


Assuntos
Envelhecimento/genética , Caenorhabditis elegans/fisiologia , Escherichia coli/genética , Microbioma Gastrointestinal/fisiologia , Redes e Vias Metabólicas/genética , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/microbiologia , Dieta/métodos , Modelos Animais de Doenças , Escherichia coli/química , Escherichia coli/metabolismo , Humanos , Desnutrição/genética , Desnutrição/metabolismo , Desnutrição/microbiologia , Obesidade/genética , Obesidade/metabolismo , Obesidade/microbiologia , Interferência de RNA , RNA Bacteriano/antagonistas & inibidores , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , Reprodução/genética , Transdução de Sinais
6.
BMC Plant Biol ; 19(1): 418, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31604418

RESUMO

BACKGROUND: So far, little is known in detail about mating systems of woody bamboos. Paternity analysis of offspring improved our understanding of these systems, and contributed to their germplasm conservation and genetic improvement. RESULTS: In this study, a paternity analysis of offspring from two consecutive mass or sporadically flowering events of Dendrocalamus membranaceus and D. sinicus were conducted to determine their mating system and pollen dispersal using the program COLONY based on simple sequence repeat (SSR) markers. Two sporadically flowering populations of D. sinicus (C1, C2) obtained relatively high paternity assignments rates (69.0-71.4%). Meanwhile, among three populations of D. membranaceus, the sporadically flowering population A also had much higher paternity assignments rates (56.4%) than mass flowering populations B1(28.6%) and B2 (42.5%). Both D. membranaceus and D. sinicus had mixed mating systems while their mating patterns were variable depending on pollination conditions. The maximum pollen dispersal distances were 90 m and 4378 m for D. membranaceus and D. sinicus populations, respectively, and the mating distances of these two species focused on ranges of ca. 0-50 m and 0-1500 m, respectively. CONCLUSIONS: These results revealed for the first time variable mating patterns in woody bamboos. This suggests half-sib seeds from the same bamboo clump may have different male parents and it is crucial to clarify genetic origin in woody bamboos' breeding programs. The results also indicate the importance of pollinators in the mating systems of tropical woody bamboos.


Assuntos
Poaceae/fisiologia , Polinização , Marcadores Genéticos , Repetições de Microssatélites , Poaceae/genética , Reprodução/genética , Especificidade da Espécie
7.
J Dairy Sci ; 102(12): 11104-11115, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31606217

RESUMO

Our aim was to estimate genetic parameters of atypical reproductive patterns and estimate their genetic correlation with milk production and classical fertility traits for commercial dairy cows. In contrast with classical fertility traits, atypical reproductive patterns based on in-line milk progesterone profiles might have higher heritability and lower genetic correlation with milk production. We had in-line milk progesterone profiles available for 12,046 cycles in 4,170 lactations of 2,589 primiparous and multiparous cows (mainly Holstein Friesian) from 14 herds. Based on progesterone profiles, 5 types of atypical reproductive patterns in a lactation were defined: delayed ovulation types I and II, persistent corpus luteum types I and II, and late embryo mortality. These atypical patterns were detected in 14% (persistent corpus luteum type II) to 21% (persistent corpus luteum type I) of lactations. In 47% of lactations, at least 1 atypical pattern was detected. Threshold model heritabilities for atypical reproduction patterns ranged between 0.03 and 0.14 and for most traits were slightly higher compared with classical fertility traits. The genetic correlation between milk yield and calving interval was 0.56, whereas genetic correlations between milk yield and atypical reproductive patterns ranged between -0.02 and 0.33. Although most of these correlations between milk yield and atypical reproductive patterns are still unfavorable, they are lower compared with the correlations between classical fertility traits and milk yield. Therefore selection against atypical reproductive patterns may relax some constraints in current dairy breeding programs, to enhance genetic progress in both fertility and milk yield at a steady pace. However, as long as the target trait for fertility is calving interval, atypical reproductive patterns will not add additional value to the breeding goal in the near future due to the low number of available records.


Assuntos
Bovinos/genética , Leite/química , Progesterona/análise , Reprodução/genética , Animais , Cruzamento , Bovinos/fisiologia , Corpo Lúteo , Feminino , Fertilidade/genética , Lactação/genética , Paridade , Fenótipo , Gravidez
8.
Genes (Basel) ; 10(10)2019 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-31614866

RESUMO

Gnetum possesses morphologically bisexual but functionally unisexual reproductive structures that exude sugary pollination drops to attract insects. Previous studies have revealed that the arborescent species (G. gnemon L.) and the lianoid species (G. luofuense C.Y.Cheng) possess different pollination syndromes. This study compared the proteome in the pollination drops of these two species using label-free quantitative techniques. The transcriptomes of fertile reproductive units (FRUs) and sterile reproductive units (SRUs) for each species were furthermore compared using Illumina Hiseq sequencing, and integrated proteomic and transcriptomic analyses were subsequently performed. Our results show that the differentially expressed proteins between FRUs and SRUs were involved in carbohydrate metabolism, the biosynthesis of amino acids and ovule defense. In addition, the differentially expressed genes between the FRUs and SRUs (e.g., MADS-box genes) were engaged in reproductive development and the formation of pollination drops. The integrated protein-transcript analyses revealed that FRUs and their exudates were relatively conservative while the SRUs and their exudates were more diverse, probably functioning as pollinator attractants. The evolution of reproductive organs appears to be synchronized with changes in the pollination drop proteome of Gnetum, suggesting that insect-pollinated adaptations are not restricted to angiosperms but also occur in gymnosperms.


Assuntos
Gnetum/metabolismo , Polinização/genética , Proteoma/metabolismo , Transcriptoma/genética , Aminoácidos/biossíntese , Aminoácidos/genética , Animais , Metabolismo dos Carboidratos/genética , Perfilação da Expressão Gênica , Gnetum/genética , Sequenciamento de Nucleotídeos em Larga Escala , Insetos/genética , Insetos/metabolismo , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/metabolismo , Magnoliopsida/genética , Óvulo Vegetal/genética , Óvulo Vegetal/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polinização/fisiologia , Proteoma/genética , Proteômica , Reprodução/genética , Açúcares/metabolismo , Transcriptoma/fisiologia
9.
Plant Sci ; 289: 110251, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31623789

RESUMO

Cytokinin Response Factors (CRFs) are a family of transcription factors which make up a side branch of the classical cytokinin two-component signaling pathway. CRFs were originally identified and have been primarily studied in Arabidopsis thaliana, although orthologs have be found throughout all land plants. Research into the evolution of CRFs as sub-group members of the larger APETALA2/Ethylene Response Factor (AP2/ERF) family has yielded interesting and useful insights related to the functional roles of CRFs in plants. Recent studies of CRFs suggest that these transcription factors are a lot more than just a group of cytokinin related genes and play important roles in both plant development and environmental stress response. This review focuses on recent advances in understanding the roles of CRFs beyond cytokinin, in reproductive development and abiotic stress response, as well as to other environmental cues.


Assuntos
Fenômenos Fisiológicos Vegetais/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Citocininas/metabolismo , Proteínas de Plantas/metabolismo , Reprodução/genética , Estresse Fisiológico/genética , Fatores de Transcrição/metabolismo
10.
BMC Plant Biol ; 19(1): 416, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31601197

RESUMO

BACKGROUND: Post-embryonic growth of land plants originates from meristems. Genetic networks in meristems maintain the stem cells and direct acquisition of cell fates. WUSCHEL-RELATED HOMEOBOX (WOX) transcription factors involved in meristem networks have only been functionally characterized in two evolutionarily distant taxa, mosses and seed plants. This report characterizes a WOX gene in a fern, which is located phylogenetically between the two taxa. RESULTS: CrWOXB transcripts were detected in proliferating tissues, including gametophyte and sporophyte meristems of Ceratopteris richardii. In addition, CrWOXB is expressed in archegonia but not the antheridia of gametophytes. Suppression of CrWOXB expression in wild-type RN3 plants by RNAi produced abnormal morphologies of gametophytes and sporophytes. The gametophytes of RNAi lines produced fewer cells, and fewer female gametes compared to wild-type. In the sporophyte generation, RNAi lines produced fewer leaves, pinnae, roots and lateral roots compared to wild-type sporophytes. CONCLUSIONS: Our results suggest that CrWOXB functions to promote cell divisions and organ development in the gametophyte and sporophyte generations, respectively. CrWOXB is the first intermediate-clade WOX gene shown to function in both generations in land plants.


Assuntos
Expressão Gênica , Genes Homeobox , Genes de Plantas , Pteridaceae/genética , Células Germinativas Vegetais/metabolismo , Meristema/genética , Brotos de Planta/genética , Reprodução/genética
11.
PLoS Biol ; 17(10): e3000478, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31639139

RESUMO

Genetic data indicate differences in speciation rate across latitudes, but underlying causes have been difficult to assess because a critical phase of the speciation process is initiated in allopatry, in which, by definition, individuals from different taxa do not interact. We conducted song playback experiments between 109 related pairs of mostly allopatric bird species or subspecies in Amazonia and North America to compare the rate of evolution of male discrimination of songs. Relative to local controls, the number of flyovers and approach to the speaker were higher in Amazonia. We estimate that responses to songs of relatives are being lost about 6 times more slowly in Amazonia than in North America. The slow loss of response holds even after accounting for differences in song frequency and song length. Amazonian species with year-round territories are losing aggressive responses especially slowly. We suggest the presence of many species and extensive interspecific territoriality favors recognition of songs sung by sympatric heterospecifics, which results in a broader window of recognition and hence an ongoing response to novel similar songs. These aggressive responses should slow the establishment of sympatry between recently diverged forms. If male responses to novel allopatric taxa reflect female responses, then premating reproductive isolation is also evolving more slowly in Amazonia. The findings are consistent with previously demonstrated slower recent rates of expansion of sister taxa into sympatry, slower rates of evolution of traits important for premating isolation, and slower rates of speciation in general in Amazonia than in temperate North America.


Assuntos
Especiação Genética , Filogenia , Reprodução/genética , Aves Canoras/classificação , Vocalização Animal/fisiologia , Animais , Brasil , Canadá , Feminino , Masculino , Peru , Filogeografia , Aves Canoras/genética , Simpatria , Estados Unidos , Gravação em Vídeo
12.
Aquat Toxicol ; 216: 105290, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31518775

RESUMO

Phthalate esters (PAEs), which are notable plasticizers, can be prolific contaminants in aquatic environments, and have been shown to induce reproductive toxicity. However, the studies concerning their toxicity towards aquatic species are based on individual chemicals, and the combined toxicity of PAEs to aquatic organisms remains unclear. The aim of this study was to explore the potential toxicity mechanisms associated with combined exposure to dibutyl phthalate (DBP) and diisobutyl phthalate (DiBP) in adult female zebrafish ovaries. Zebrafish were exposed to DBP, DiBP and their mixtures for 30 days, and their effects on ovarian histology, plasma sex hormones and ovarian transcriptomics were investigated. Plasma estradiol (E2) levels were significantly decreased by 38.9% in the DBP-1133 exposure group and 41.0% in the DiBP-1038 exposure group. The percentage of late/mature oocytes was also significantly decreased by 17.3% under DBP-1133 exposure and 16.2% under DiBP-1038 exposure, while that under combined exposure was not significantly affected. Nevertheless, transcriptome sequencing revealed 2564 differentially expressed genes (DEGs) in zebrafish ovaries after exposure to the mixtures. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the DEGs were involved in the neuroactive ligand-receptor interaction, GnRH, progesterone-mediated oocyte maturation, oocyte meiosis and steroid hormone biosynthesis signaling pathways. These results revealed that combined exposure exerts potential reproductive toxicity at the molecular level.


Assuntos
Dibutilftalato/análogos & derivados , Dibutilftalato/toxicidade , Exposição Ambiental , Perfilação da Expressão Gênica , Ovário/metabolismo , Transcriptoma/genética , Peixe-Zebra/genética , Animais , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Ontologia Genética , Hormônios Esteroides Gonadais/sangue , Ovário/efeitos dos fármacos , Ovário/patologia , Reprodutibilidade dos Testes , Reprodução/efeitos dos fármacos , Reprodução/genética , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/sangue
13.
J Steroid Biochem Mol Biol ; 195: 105483, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31550505

RESUMO

Hydroxysteroid 17-Beta Dehydrogenase 3 (Hsd17b3), primarily expressed in Leydig cells (LCs) of the mammalian testes, is essential for testosterone biosynthesis and male fertility. The aim of our study was to profile the expression, splice variants (SV) and novel insertion/deletion (indel) of Hsd17b3 in boars. Quantitative analysis showed that the expression level of Hsd17b3 in the testis was significantly highest. Among different testicular cell types, the Hsd17b3 mRNA expression level of LCs was significantly higher than that of SSCs (spermatogonial stem cells) and SCs (Sertoli cells). Furthermore, the SV was firstly identified in pigs and it was highly expressed in LCs comparing with SSCs and SCs. In addition, two mutations were identified in pig Hsd17b3 gene promotor and intron, respectively, which were associated with male reproductive traits (P <  0.05). In conclusion, both transcripts of Hsd17b3 gene were highly expressed in pig testes and LCs; the two novel indel variants of Hsd17b3 gene can be used as potential DNA makers for the marker-assisted selection in pigs. All these findings would enrich the study of Hsd17b3 gene in pig genetic breeding.


Assuntos
17-Hidroxiesteroide Desidrogenases/genética , Células Intersticiais do Testículo/metabolismo , Reprodução/genética , Sus scrofa/genética , Células-Tronco Germinativas Adultas/metabolismo , Processamento Alternativo , Animais , Variação Genética , Mutação INDEL , Masculino , Regiões Promotoras Genéticas , Células de Sertoli/metabolismo
14.
J Biosci ; 44(4)2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31502584

RESUMO

The role of genetic relatedness in social evolution has recently come under critical attention. These arguments are here critically analyzed, both theoretically and empirically. It is argued that when the conceptual structure of the theory of natural selection is carefully taken into account, genetic relatedness can be seen to play an indispensable role in the evolution of both facultative and advanced eusociality. Although reviewing the empirical evidence concerning the evolution of eusociality reveals that relatedness does not play a role in the initial appearance of helper phenotypes, this follows simply from the fact that natural selection - of which relatedness is a necessary component - does not play a causal role in the origin of any traits. Further, separating two logically distinct elements of causal explanation - necessity and sufficiency - explains why the debate lingers on: although relatedness plays a necessary role in the evolution of helping and advanced eusociality, relatedness alone is not sufficient for their appearance. Therefore, if the relatedness variable in a given data set is held at a uniformly high value, then it indeed may turn out that other factors occupy a more prominent role. However, this does not change the fact that high relatedness functions as a necessary background condition for the evolution of advanced eusociality.


Assuntos
Comportamento Animal/fisiologia , Aptidão Genética/fisiologia , Insetos/fisiologia , Seleção Genética/genética , Animais , Aptidão Genética/genética , Insetos/genética , Reprodução/genética , Reprodução/fisiologia , Seleção Genética/fisiologia , Comportamento Social , Sociobiologia
15.
BMC Cancer ; 19(1): 926, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31533668

RESUMO

BACKGROUND: Reproductive characteristics are well-established risk factors for breast cancer, but the underlying mechanisms are not fully resolved. We hypothesized that altered DNA methylation, measured in tumor tissue, could act in concert with reproductive factors to impact breast carcinogenesis. METHODS: Among a population-based sample of women newly diagnosed with first primary breast cancer, reproductive history was assessed using a life-course calendar approach in an interviewer-administered questionnaire. Methylation-specific polymerase chain reaction and Methyl Light assays were used to assess gene promotor methylation status (methylated vs. unmethylated) for 13 breast cancer-related genes in archived breast tumor tissue. We used case-case unconditional logistic regression to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for associations with age at menarche and parity (among 855 women), and age at first birth and lactation (among a subset of 736 parous women) in association with methylation status. RESULTS: Age at first birth > 27 years, compared with < 23 years, was associated with lower odds of methylation of CDH1 (OR = 0.44, 95% CI = 0.20-0.99) and TWIST1 (OR = 0.48, 95% CI = 0.28-0.82), and higher odds of methylation of BRCA1 (OR = 1.63, 95% CI = 1.14-2.35). Any vs. no lactation was associated with higher odds of methylation of the PGR gene promoter (OR = 1.59, 95% CI = 1.01-2.49). No associations were noted for parity and methylation in any of the genes assayed. CONCLUSIONS: Our findings indicate that age at first birth, lactation and, perhaps age at menarche, are associated with gene promoter methylation in breast cancer, and should be confirmed in larger studies with robust gene coverage.


Assuntos
Neoplasias da Mama/genética , Metilação de DNA , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/genética , Proteína BRCA1/genética , Biomarcadores Tumorais , Neoplasias da Mama/patologia , Neoplasias da Mama/fisiopatologia , Caderinas/genética , DNA de Neoplasias/metabolismo , Feminino , Humanos , Lactação/genética , Menarca/genética , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Paridade/genética , Gravidez , Regiões Promotoras Genéticas , Receptores de Progesterona/genética , Reprodução/genética , Fatores de Risco , Proteína 1 Relacionada a Twist/genética , Adulto Jovem
16.
PLoS Genet ; 15(9): e1008394, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31536509

RESUMO

Courtship is pivotal for successful mating. However, courtship is challenging for the Cryptococcus neoformans species complex, comprised of opportunistic fungal pathogens, as the majority of isolates are α mating type. In the absence of mating partners of the opposite mating type, C. deneoformans can undergo unisexual reproduction, during which a yeast-to-hyphal morphological transition occurs. Hyphal growth during unisexual reproduction is a quantitative trait, which reflects a strain's ability to undergo unisexual reproduction. In this study, we determined whether unisexual reproduction confers an ecological benefit by promoting foraging for mating partners. Through competitive mating assays using strains with different abilities to produce hyphae, we showed that unisexual reproduction potential did not enhance competition for mating partners of the same mating type, but when cells of the opposite mating type were present, cells with enhanced hyphal growth were more competitive for mating partners of either the same or opposite mating type. Enhanced mating competition was also observed in a strain with increased hyphal production that lacks the mating repressor gene GPA3, which contributes to the pheromone response. Hyphal growth in unisexual strains also enables contact between adjacent colonies and enhances mating efficiency during mating confrontation assays. The pheromone response pathway activation positively correlated with unisexual reproduction hyphal growth during bisexual mating and exogenous pheromone promoted bisexual cell fusion. Despite the benefit in competing for mating partners, unisexual reproduction conferred a fitness cost. Taken together, these findings suggest C. deneoformans employs hyphal growth to facilitate contact between colonies at long distances and utilizes pheromone sensing to enhance mating competition.


Assuntos
Cryptococcus neoformans/genética , Genes Fúngicos Tipo Acasalamento/genética , Reprodução Assexuada/fisiologia , Comunicação Celular , Fusão Celular , Cryptococcus/genética , Cryptococcus/patogenicidade , Cryptococcus neoformans/patogenicidade , Proteínas Fúngicas/genética , Genes Fúngicos Tipo Acasalamento/fisiologia , Hifas/genética , Feromônios , Reprodução/genética , Reprodução Assexuada/genética
17.
Int J Mol Sci ; 20(18)2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31540031

RESUMO

Multiple genes, whose functions or expression are overlapping, compensate for the loss of one gene. A gene cluster in the mouse genome encodes five seminal vesicle proteins (SVS2, SVS3, SVS4, SVS5, and SVS6). These proteins are produced by male rodents and function in formation of the copulatory plug following mating. SVS2 plays an essential role in the successful internal fertilization by protecting the sperm membrane against a uterine immune attack. We hypothesized that the four remaining seminal vesicle proteins (SVPs) of this gene cluster may partially/completely compensate for the deficiency of SVS2. For confirming our hypothesis, we generated mice lacking the entire SVP-encoding gene cluster and compared their fecundity with Svs2-deficient (Svs2-/-) mice; that is, mice deficient in Svs2 alone. A single loxP site remained after the deletion of the Svs2 gene. Therefore, we inserted another loxP site by combining the CRISPR/Cas9 system with single-stranded oligodeoxynucleotides (ssODN). Male mice lacking the entire SVP-encoding gene cluster (Svs2-6-/- mice) and thereby all five SVP proteins, generated by the deletion of 100kbp genomic DNA, showed low fecundity. However, the fecundity level was comparable with that from Svs2-/- male mice. Our results demonstrate that SVS3, SVS4, SVS5, and SVS6 do not function in the protection of sperm against a uterine immune attack in the absence of SVS2. Thus, Svs2 is the critical gene in the SVP gene cluster.


Assuntos
Fertilidade/genética , Proteínas Secretadas pela Vesícula Seminal/genética , Animais , Feminino , Fertilidade/imunologia , Masculino , Camundongos , Família Multigênica , Reprodução/genética , Proteínas Secretadas pela Vesícula Seminal/metabolismo , Proteínas Secretadas pela Vesícula Seminal/fisiologia , Deleção de Sequência/genética , Espermatozoides/metabolismo , Útero/imunologia , Útero/metabolismo
18.
BMC Genomics ; 20(1): 693, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477015

RESUMO

BACKGROUND: Seasonal timing of breeding is a life history trait with major fitness consequences but the genetic basis of the physiological mechanism underlying it, and how gene expression is affected by date and temperature, is not well known. In order to study this, we measured patterns of gene expression over different time points in three different tissues of the hypothalamic-pituitary-gonadal-liver axis, and investigated specifically how temperature affects this axis during breeding. We studied female great tits (Parus major) from lines artificially selected for early and late timing of breeding that were housed in two contrasting temperature environments in climate-controlled aviaries. We collected hypothalamus, liver and ovary samples at three different time points (before and after onset of egg-laying). For each tissue, we sequenced whole transcriptomes of 12 pools (n = 3 females) to analyse gene expression. RESULTS: Birds from the selection lines differed in expression especially for one gene with clear reproductive functions, zona pellucida glycoprotein 4 (ZP4), which has also been shown to be under selection in these lines. Genes were differentially expressed at different time points in all tissues and most of the differentially expressed genes between the two temperature treatments were found in the liver. We identified a set of hub genes from all the tissues which showed high association to hormonal functions, suggesting that they have a core function in timing of breeding. We also found ample differentially expressed genes with largely unknown functions in birds. CONCLUSIONS: We found differentially expressed genes associated with selection line and temperature treatment. Interestingly, the latter mainly in the liver suggesting that temperature effects on egg-laying date may happen down-stream in the physiological pathway. These findings, as well as our datasets, will further the knowledge of the mechanisms of tissue-specific avian seasonality in the future.


Assuntos
Regulação da Expressão Gênica , Reprodução/genética , Aves Canoras/genética , Animais , Cruzamento , Feminino , Ontologia Genética , Redes Reguladoras de Genes , Hipotálamo/metabolismo , Fígado/metabolismo , Especificidade de Órgãos , Ovário/metabolismo , Reprodução/fisiologia , Aves Canoras/metabolismo , Temperatura Ambiente , Fatores de Tempo , Transcriptoma
19.
BMC Genomics ; 20(1): 695, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481029

RESUMO

BACKGROUND: Little is known about the genetic architecture of economically important traits in Brown Swiss cattle because only few genome-wide association studies (GWAS) have been carried out in this breed. Moreover, most GWAS have been performed for single traits, thus not providing detailed insights into potentially existing pleiotropic effects of trait-associated loci. RESULTS: To compile a comprehensive catalogue of large-effect quantitative trait loci (QTL) segregating in Brown Swiss cattle, we carried out association tests between partially imputed genotypes at 598,016 SNPs and daughter-derived phenotypes for more than 50 economically important traits, including milk production, growth and carcass quality, body conformation, reproduction and calving traits in 4578 artificial insemination bulls from two cohorts of Brown Swiss cattle (Austrian-German and Swiss populations). Across-cohort multi-trait meta-analyses of the results from the single-trait GWAS revealed 25 quantitative trait loci (QTL; P < 8.36 × 10- 8) for economically relevant traits on 17 Bos taurus autosomes (BTA). Evidence of pleiotropy was detected at five QTL located on BTA5, 6, 17, 21 and 25. Of these, two QTL at BTA6:90,486,780 and BTA25:1,455,150 affect a diverse range of economically important traits, including traits related to body conformation, calving, longevity and milking speed. Furthermore, the QTL at BTA6:90,486,780 seems to be a target of ongoing selection as evidenced by an integrated haplotype score of 2.49 and significant changes in allele frequency over the past 25 years, whereas either no or only weak evidence of selection was detected at all other QTL. CONCLUSIONS: Our findings provide a comprehensive overview of QTL segregating in Brown Swiss cattle. Detected QTL explain between 2 and 10% of the variation in the estimated breeding values and thus may be considered as the most important QTL segregating in the Brown Swiss cattle breed. Multi-trait association testing boosts the power to detect pleiotropic QTL and assesses the full spectrum of phenotypes that are affected by trait-associated variants.


Assuntos
Bovinos/genética , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas/genética , Animais , Cruzamento , Bovinos/crescimento & desenvolvimento , Bovinos/metabolismo , Bovinos/fisiologia , Feminino , Pleiotropia Genética , Longevidade/genética , Masculino , Leite/metabolismo , Fenótipo , Polimorfismo de Nucleotídeo Único , Reprodução/genética
20.
Nat Commun ; 10(1): 3972, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481692

RESUMO

Genetic exchange enables parasites to rapidly transform disease phenotypes and exploit new host populations. Trypanosoma cruzi, the parasitic agent of Chagas disease and a public health concern throughout Latin America, has for decades been presumed to exchange genetic material rarely and without classic meiotic sex. We present compelling evidence from 45 genomes sequenced from southern Ecuador that T. cruzi in fact maintains truly sexual, panmictic groups that can occur alongside others that remain highly clonal after past hybridization events. These groups with divergent reproductive strategies appear genetically isolated despite possible co-occurrence in vectors and hosts. We propose biological explanations for the fine-scale disconnectivity we observe and discuss the epidemiological consequences of flexible reproductive modes. Our study reinvigorates the hunt for the site of genetic exchange in the T. cruzi life cycle, provides tools to define the genetic determinants of parasite virulence, and reforms longstanding theory on clonality in trypanosomatid parasites.


Assuntos
Genoma de Protozoário , Meiose , Trypanosoma cruzi/genética , Animais , Doença de Chagas/parasitologia , Quirópteros/parasitologia , Equador , Variação Genética , Genética Populacional , Recombinação Genética , Reprodução/genética , Roedores/parasitologia , Análise de Sequência de DNA , Triatominae/parasitologia
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