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1.
Sci Rep ; 11(1): 17649, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34480051

RESUMO

The ubiquitous activity of humans is a fundamental feature of urban environments affecting local wildlife in several ways. Testing the influence of human disturbance would ideally need experimental approach, however, in cities, this is challenging at relevant spatial and temporal scales. Thus, to better understand the ecological effects of human activity, we exploited the opportunity that the city-wide lockdowns due to the COVID-19 pandemic provided during the spring of 2020. We assessed changes in reproductive success of great tits (Parus major) at two urban habitats affected strikingly differently by the 'anthropause', and at an unaffected forest site. Our results do not support that urban great tits benefited from reduced human mobility during the lockdown. First, at one of our urban sites, the strongly (- 44%) reduced human disturbance in 2020 (compared to a long-term reference period) did not increase birds' reproductive output relative to the forest habitat where human disturbance was low in all years. Second, in the other urban habitat, recreational human activity considerably increased (+ 40%) during the lockdown and this was associated with strongly reduced nestling body size compared to the pre-COVID reference year. Analyses of other environmental factors (meteorological conditions, lockdown-induced changes in air pollution) suggest that these are not likely to explain our results. Our study supports that intensified human disturbance can have adverse fitness consequences in urban populations. It also highlights that a few months of 'anthropause' is not enough to counterweight the detrimental impacts of urbanization on local wildlife populations.


Assuntos
COVID-19 , Ecossistema , Quarentena , Reprodução/fisiologia , SARS-CoV-2 , Aves Canoras/fisiologia , Animais , COVID-19/epidemiologia , COVID-19/prevenção & controle , Cidades/epidemiologia , Feminino , Humanos , Masculino
2.
Zoolog Sci ; 38(4): 352-358, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34342956

RESUMO

A new species of brittle star, Ophiodelos okayoshitakai, is described from two specimens collected in Sagami Bay, central-eastern Japan. Photographic examination of the holotype specimen of the sole other congener, Ophiodelos insignis Koehler, 1930, indicates that Ophiodelos okayoshitakai sp. nov. is distinguished from O. insignis by i) the disc stumps covering on the dorsal side of the disc, ii) the dorsal and ventral arm plates being separated from each other on the proximal arm regions, iii) the dorsal arm plate being smooth, iv) the arm spines at proximal portion of the arm being six in number and smooth in shape, and v) the number and shape of the tentacle scales at proximal portion of the arm being up to two and spine-shaped adradially and oval abradially. Detailed morphological observations of this new species suggest the inclusion of Ophiodelos, whose familial affiliation remains unclear, in the suborder Ophiacanthina. More than 10 juveniles of various sizes were found in the disc of Ophiodelos okayoshitakai sp. nov., indicating a brooding reproduction. This is the first report of the genus Ophiodelos from Japanese waters. We also provided a nucleotide sequence for part of the cytochrome c oxidase subunit I (COI) gene in O. okayoshitakai sp. nov. for future studies of DNA barcoding and phylogeny.


Assuntos
Equinodermos/fisiologia , Reprodução/fisiologia , Animais , Japão , Oceano Pacífico
3.
J Genet ; 1002021.
Artigo em Inglês | MEDLINE | ID: mdl-34282732

RESUMO

Rice is one of the most important cereals of the world, with a substantial amount of genetic variation, and a staple food for more than half of the world's population. Salinity is the second most important abiotic stress after drought that adversely affects rice production globally. Both the seedling and reproductive stages are extremely sensitive to salinity but tolerant at the reproductive stage which is most crucial, as it translates into grain yield. Therefore, it is more important to identify the underlying factors of tolerance at the reproductive stage as a necessary step towards improving varieties for salinity environments. However, because of the difficulties in phenotyping protocols of salinity tolerance screening at the reproductive stage, only a few studies exist on this aspect. In view of this, a study involving 188 F4 rice lines derived from a cross CSR28 × Sadri along with the parents was carried out for phenotyping using a novel screening approach for the reproductive stage in salinity conditions and genotyping by SNP markers (Infinium Illumina 6K SNP chip) to construct a high-saturation linkage map. Quantitative trait loci analysis in an F4 population for physiological traits (chlorophyll a, chlorophyll b and carotenoid) and agronomic traits (plant height, filled grain number, grain yield and spikelet fertility percentage) led to the identification of 14 QTLs with an LOD range of 2.72-4.46 explaining phenotypic variation of 5.29-24.86% on chromosomes 1, 2, 3, 5, 6, 7 and 8. Tolerant alleles were contributed by both CSR28 and Sadri. The results indicated that both physiological and agronomic traits were involved in salinity tolerance at the reproductive stage and majority of the QTLs identified in this study are reported for the first time.


Assuntos
Oryza/genética , Locos de Características Quantitativas/genética , Estresse Salino/genética , Tolerância ao Sal/genética , Alelos , Mapeamento Cromossômico/métodos , Cromossomos de Plantas , Genótipo , Oryza/crescimento & desenvolvimento , Oryza/fisiologia , Fenótipo , Reprodução/genética , Reprodução/fisiologia , Plântula/genética
4.
Int J Mol Sci ; 22(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34281188

RESUMO

Endometriosis is a disease of reproductive age characterized by chronic pelvic pain and infertility. Its pathogenesis is complex and still partially unexplained. However, there is increasing evidence of the role of chronic inflammation, immune system dysregulation, and oxidative stress in its development and progression. The latter appears to be involved in multiple aspects of the disease. Indeed, disease progression sustained by a hyperproliferative phenotype can be related to reactive oxygen species (ROS) imbalance, as numerous experiments using drugs to counteract hyperproliferation have shown in recent years. Chronic pelvic pain is also associated with cell function dysregulation favoring chronic inflammation and oxidative stress, specifically involving macrophages and mast cell activation. Moreover, there is increasing evidence of a role for ROS and impaired mitochondrial function not only as deleterious effectors of the ovarian reserve in patients with endometriomas but also in terms of oocyte quality and, hence, embryo development impairment. Targeting oxidative stress looks to be a promising strategy to both curb endometriotic lesion progression and alleviate endometriosis-associated symptoms of chronic pain and infertility. More investigations are nevertheless needed to develop effective therapeutic strategies for clinical application.


Assuntos
Endometriose/metabolismo , Endometriose/terapia , Estresse Oxidativo/fisiologia , Antioxidantes/uso terapêutico , Endometriose/patologia , Feminino , Humanos , Infertilidade Feminina/etiologia , Oócitos/patologia , Dor Pélvica/etiologia , Espécies Reativas de Oxigênio , Reprodução/fisiologia
5.
Genes (Basel) ; 12(5)2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-34068942

RESUMO

Phylogenetic trees based on multiple genomic loci enable us to estimate the evolution of functional constraints that operate on genes based on lineage-specific fluctuation of the evolutionary rate at particular gene loci, "gene-branch interactions". Using this information as predictors, our previous work inferred that the common ancestor of placental mammals was nocturnal, insectivorous, solitary, and bred seasonally. Here, we added seven new continuous traits including lifespan, bodyweight, and five reproduction-related traits and inferred the coevolution network of 14 core life history traits for 89 mammals. In this network, bodyweight and lifespan are not directly connected to each other; instead, their correlation is due to both of them coevolving with gestation period. Diurnal mammals are more likely to be monogamous than nocturnal mammals, while arboreal mammals tend to have a smaller litter size than terrestrial mammals. Coevolution between diet and the seasonal breeding behavior test shows that year-round breeding preceded the dietary change to omnivory, while seasonal breeding preceded the dietary change to carnivory. We also discuss the evolution of reproductive strategy of mammals. Genes selected as predictors were identified as well; for example, genes function as tumor suppressor were selected as predictors of weaning age.


Assuntos
Mamíferos/genética , Mamíferos/fisiologia , Reprodução/genética , Reprodução/fisiologia , Animais , Peso Corporal/genética , Peso Corporal/fisiologia , Feminino , Genoma/genética , Tamanho da Ninhada de Vivíparos/genética , Tamanho da Ninhada de Vivíparos/fisiologia , Longevidade/genética , Longevidade/fisiologia , Filogenia , Placenta/fisiologia , Gravidez
6.
Development ; 148(13)2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34128976

RESUMO

5,10-Methylenetetrahydrofolate reductase (MTHFR) is a crucial enzyme in the folate metabolic pathway with a key role in generating methyl groups. As MTHFR deficiency impacts male fertility and sperm DNA methylation, there is the potential for epimutations to be passed to the next generation. Here, we assessed whether the impact of MTHFR deficiency on testis morphology and sperm DNA methylation is exacerbated across generations in mouse. Although MTHFR deficiency in F1 fathers has only minor effects on sperm counts and testis weights and histology, F2 generation sons show further deterioration in reproductive parameters. Extensive loss of DNA methylation is observed in both F1 and F2 sperm, with >80% of sites shared between generations, suggestive of regions consistently susceptible to MTHFR deficiency. These regions are generally methylated during late embryonic germ cell development and are enriched in young retrotransposons. As retrotransposons are resistant to reprogramming of DNA methylation in embryonic germ cells, their hypomethylated state in the sperm of F1 males could contribute to the worsening reproductive phenotype observed in F2 MTHFR-deficient males, compatible with the intergenerational passage of epimutations.


Assuntos
Metilação de DNA , Metilenotetra-Hidrofolato Redutase (NADPH2)/deficiência , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Reprodução/fisiologia , Retroelementos/genética , Animais , Epigenômica , Pai , Feminino , Ácido Fólico/metabolismo , Células Germinativas , Homocistinúria , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Espasticidade Muscular , Transtornos Psicóticos , Espermatozoides/metabolismo
7.
Commun Biol ; 4(1): 795, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34172814

RESUMO

The underlying molecular mechanisms that determine long day versus short day breeders remain unknown in any organism. Atlantic herring provides a unique opportunity to examine the molecular mechanisms involved in reproduction timing, because both spring and autumn spawners exist within the same species. Although our previous whole genome comparisons revealed a strong association of TSHR alleles with spawning seasons, the functional consequences of these variants remain unknown. Here we examined the functional significance of six candidate TSHR mutations strongly associated with herring reproductive seasonality. We show that the L471M missense mutation in the spring-allele causes enhanced cAMP signaling. The best candidate non-coding mutation is a 5.2 kb retrotransposon insertion upstream of the TSHR transcription start site, near an open chromatin region, which is likely to affect TSHR expression. The insertion occurred prior to the split between Pacific and Atlantic herring and was lost in the autumn-allele. Our study shows that strongly associated coding and non-coding variants at the TSHR locus may both contribute to the regulation of seasonal reproduction in herring.


Assuntos
Peixes/fisiologia , Receptores da Tireotropina/genética , Alelos , Animais , Oceano Atlântico , Sequência Conservada , Haplótipos , Mutação , Receptores da Tireotropina/fisiologia , Reprodução/fisiologia , Estações do Ano , Transdução de Sinais , Tireotropina Subunidade beta/genética
8.
Commun Biol ; 4(1): 723, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34117363

RESUMO

Harmonic convergence is a potential cue, female mosquitoes use to choose male mates. However, very little is known about the benefits this choice confers to offspring performance. Using Aedes aegypti (an important vector of human disease), we investigated whether offspring of converging parental pairs showed differences in immune competence compared to offspring derived from non-converging parental pairs. Here we show that harmonic convergence, along with several other interacting factors (sex, age, reproductive, and physiological status), significantly shaped offspring immune responses (melanization and response to a bacterial challenge). Harmonic convergence had a stronger effect on the immune response of male offspring than on female offspring. Further, female offspring from converging parental pairs disseminated dengue virus more quickly than offspring derived from non-converging parental pairs. Our results provide insight into a wide range of selective pressures shaping mosquito immune function and could have important implications for disease transmission and control.


Assuntos
Aedes/fisiologia , Acústica , Aedes/imunologia , Aedes/virologia , Fatores Etários , Animais , Vírus da Dengue/fisiologia , Feminino , Masculino , Reprodução/fisiologia , Fatores Sexuais , Comportamento Sexual Animal/fisiologia
9.
Aging (Albany NY) ; 13(12): 16873-16894, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34156973

RESUMO

Female reproductive aging is, in a way, a biological phenomenon that develops along canonical molecular pathways; however, it has particular features. Recent studies revealed complexity of the interconnections between reproductive aging and aging of other systems, and even suggested a cause-effect uncertainty between them. It was also shown that reproductive aging can impact aging processes in an organism at the level of cells, tissues, organs, and systems. Women at the end of their reproductive lives are characterized by the accelerated incidence of age-related diseases. Timing of the onset of menarche and menopause and variability in the duration of reproductive life carry a latent social risk: not having enough information about the reproductive potential, women keep on postponing childbirth. Identification and use of the most accurate and sensitive aging biomarkers enable the prediction of menopause timing and quantification of the true biological and reproductive ages of an organism. We discuss current views on reproductive aging and peculiarities of using available biomarkers of aging. We also consider latest advances in the search for potential genetic markers of reproductive aging. Finally, we posit the importance of determining the female biological age and highlight potential research directions in this area.


Assuntos
Biomarcadores/metabolismo , Longevidade/fisiologia , Reprodução/fisiologia , Relógios Circadianos , Feminino , Marcadores Genéticos , Humanos , Mitocôndrias/metabolismo
10.
Nat Commun ; 12(1): 3442, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34117253

RESUMO

Rapid climate warming is altering Arctic and alpine tundra ecosystem structure and function, including shifts in plant phenology. While the advancement of green up and flowering are well-documented, it remains unclear whether all phenophases, particularly those later in the season, will shift in unison or respond divergently to warming. Here, we present the largest synthesis to our knowledge of experimental warming effects on tundra plant phenology from the International Tundra Experiment. We examine the effect of warming on a suite of season-wide plant phenophases. Results challenge the expectation that all phenophases will advance in unison to warming. Instead, we find that experimental warming caused: (1) larger phenological shifts in reproductive versus vegetative phenophases and (2) advanced reproductive phenophases and green up but delayed leaf senescence which translated to a lengthening of the growing season by approximately 3%. Patterns were consistent across sites, plant species and over time. The advancement of reproductive seasons and lengthening of growing seasons may have significant consequences for trophic interactions and ecosystem function across the tundra.


Assuntos
Fenômenos Fisiológicos Vegetais , Plantas , Reprodução/fisiologia , Tundra , Regiões Árticas , Clima , Ecossistema , Flores , Modelos Biológicos , Fenótipo , Plantas/genética , Estações do Ano , Análise Espaço-Temporal , Temperatura
11.
Nat Commun ; 12(1): 3717, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162841

RESUMO

Rawls argued that fairness in human societies can be achieved if decisions about the distribution of societal rewards are made from behind a veil of ignorance, which obscures the personal gains that result. Whether ignorance promotes fairness in animal societies, that is, the distribution of resources to reduce inequality, is unknown. Here we show experimentally that cooperatively breeding banded mongooses, acting from behind a veil of ignorance over kinship, allocate postnatal care in a way that reduces inequality among offspring, in the manner predicted by a Rawlsian model of cooperation. In this society synchronized reproduction leaves adults in a group ignorant of the individual parentage of their communal young. We provisioned half of the mothers in each mongoose group during pregnancy, leaving the other half as matched controls, thus increasing inequality among mothers and increasing the amount of variation in offspring birth weight in communal litters. After birth, fed mothers provided extra care to the offspring of unfed mothers, not their own young, which levelled up initial size inequalities among the offspring and equalized their survival to adulthood. Our findings suggest that a classic idea of moral philosophy also applies to the evolution of cooperation in biological systems.


Assuntos
Comportamento Animal/fisiologia , Herpestidae/fisiologia , Reprodução/fisiologia , Comportamento Social , Animais , Animais Recém-Nascidos , Peso Corporal/fisiologia , Cruzamento , Feminino , Masculino , Modelos Teóricos , Gravidez , Predomínio Social
12.
PLoS Negl Trop Dis ; 15(5): e0009363, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33945524

RESUMO

Species usually develop reproductive isolation mechanisms allowing them to avoid interbreeding. These preventive barriers can act before reproduction, "pre-zygotic barriers", or after reproduction, "post-zygotic barriers". Pre-zygotic barriers prevent unfavourable mating, while post-zygotic barriers determine the viability and selective success of the hybrid offspring. Hybridization in parasites and the underlying reproductive isolation mechanisms maintaining their genetic integrity have been overlooked. Using an integrated approach this work aims to quantify the relative importance of pre-zygotic barriers in Schistosoma haematobium x S. bovis crosses. These two co-endemic species cause schistosomiasis, one of the major debilitating parasitic diseases worldwide, and can hybridize naturally. Using mate choice experiments we first tested if a specific mate recognition system exists between both species. Second, using RNA-sequencing we analysed differential gene expression between homo- and hetero-specific pairing in male and female adult parasites. We show that homo- and hetero-specific pairing occurs randomly between these two species, and few genes in both sexes are affected by hetero-specific pairing. This suggests that i) mate choice is not a reproductive isolating factor, and that ii) no pre-zygotic barrier except spatial isolation "by the final vertebrate host" seems to limit interbreeding between these two species. Interestingly, among the few genes affected by the pairing status of the worms, some can be related to pathways affected during male and female interactions and may also present interesting candidates for species isolation mechanisms and hybridization in schistosome parasites.


Assuntos
Mosaicismo/embriologia , Reprodução/fisiologia , Isolamento Reprodutivo , Schistosoma haematobium/classificação , Animais , Cricetinae , Feminino , Regulação da Expressão Gênica , Especiação Genética , Masculino , Schistosoma haematobium/embriologia , Schistosoma haematobium/crescimento & desenvolvimento
13.
BMC Vet Res ; 17(1): 179, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33931072

RESUMO

BACKGROUND: The varroa mite is one of the main causes of honey bee mortality. An important mechanism by which honey bees increase their resistance against this mite is the expression of suppressed mite reproduction. This trait describes the physiological inability of mites to produce viable offspring and was found associated with eight genomic variants in previous research. RESULTS: This paper presents the development and validation of high-throughput qPCR assays with dual-labeled probes for discriminating these eight single-nucleotide variants. Amplicon sequences used for assay validation revealed additional variants in the primer/probe binding sites in four out of the eight assays. As for two of these the additional variants interfered with the genotyping outcome supplementary primers and/or probes were developed. Inclusion of these primers and probes in the assay mixes allowed for the correct genotyping of all eight variants of interest within our bee population. CONCLUSION: These outcomes underline the importance of checking for interfering variants in designing qPCR assays. Ultimately, the availability of this assay allows genotyping for the suppressed mite reproduction trait and paves the way for marker assisted selection in breeding programs.


Assuntos
Abelhas/genética , Abelhas/parasitologia , Interações Hospedeiro-Parasita/genética , Animais , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Reação em Cadeia da Polimerase em Tempo Real , Reprodução/fisiologia , Varroidae
14.
Commun Biol ; 4(1): 555, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976359

RESUMO

Meiosis is a core feature of eukaryotes that occurs in all major groups, including the early diverging excavates. In this group, meiosis and production of haploid gametes have been described in the pathogenic protist, Trypanosoma brucei, and mating occurs in the salivary glands of the insect vector, the tsetse fly. Here, we searched for intermediate meiotic stages among trypanosomes from tsetse salivary glands. Many different cell types were recovered, including trypanosomes in Meiosis I and gametes. Significantly, we found trypanosomes containing three nuclei with a 1:2:1 ratio of DNA contents. Some of these cells were undergoing cytokinesis, yielding a mononucleate gamete and a binucleate cell with a nuclear DNA content ratio of 1:2. This cell subsequently produced three more gametes in two further rounds of division. Expression of the cell fusion protein HAP2 (GCS1) was not confined to gametes, but also extended to meiotic intermediates. We propose a model whereby the two nuclei resulting from Meiosis I undergo asynchronous Meiosis II divisions with sequential production of haploid gametes.


Assuntos
Células Germinativas/metabolismo , Reprodução/fisiologia , Trypanosoma/genética , Animais , Núcleo Celular/genética , Núcleo Celular/metabolismo , DNA/genética , Células Germinativas/fisiologia , Meiose/genética , Meiose/fisiologia , Trypanosoma/metabolismo , Trypanosoma/fisiologia , Moscas Tsé-Tsé/genética
15.
Toxicology ; 457: 152810, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33984407

RESUMO

With the rapid development of economic globalization and industrialization, lead (Pb), one of the most important heavy metals, has been used widely since antiquity for several purposes. In fact, its impact on the health of animals and humans is a significant public health risk all the time. Pb could be accumulated in the body for a long time, causing irreversible damage to the health of animals and humans, including hostile reproductive health. Up to now, although there are some published studies on impeding the normal development of ovarian folliculogenesis of female resulted from Pb exposure, with the damage of structure in uterine tissue, the imbalance of female menstrual status, and the change of hormone levels. The potential mechanism of Pb exposure on female reproduction system, however, remains enigmatic. How to alleviate the damage of Pb toxicity to reproductive function of female has become an urgent problem. Therefore, the aim of the present review is to discuss the information on the growth and development of ovarian follicle of mammalians and the potential toxic mechanism when exposed to Pb. The literatures were collected via various websites and consulting books, reports, etc. In summary, Pb impair folliculogenesis of mammalians, which may be related to the interference to the hypothalamic-pituitary-gonadal (HPG) axis and the production of reactive oxygen species (ROS), in turn impairs various molecules including proteins, lipids and DNA, as well as the disruption of the antioxidant defense system, ionic equilibrium and endoplasmic reticulum homeostasis.


Assuntos
Intoxicação por Chumbo/metabolismo , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Estresse Oxidativo/efeitos dos fármacos , Animais , Feminino , Humanos , Folículo Ovariano/metabolismo , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Reprodução/efeitos dos fármacos , Reprodução/fisiologia
16.
Mol Biochem Parasitol ; 243: 111371, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33872659

RESUMO

Much of the vast evolutionary landscape occupied by Eukaryotes is dominated by protists. Though parasitism has arisen in many lineages, there are three main groups of parasitic protists of relevance to human and livestock health: the Apicomplexa, including the malaria parasite Plasmodium and coccidian pathogens of livestock such as Eimeria; the excavate flagellates, encompassing a diverse range of protist pathogens including trypanosomes, Leishmania, Giardia and Trichomonas; and the Amoebozoa, including pathogenic amoebae such as Entamoeba. These three groups represent separate, deep branches of the eukaryote tree, underlining their divergent evolutionary histories. Here, I explore what is known about sex in these three main groups of parasitic protists.


Assuntos
Amebozoários/fisiologia , Apicomplexa/fisiologia , Reprodução/fisiologia , Trypanosoma/fisiologia , Animais , Apicomplexa/patogenicidade , DNA de Cinetoplasto , Eucariotos/fisiologia , Feminino , Células Germinativas/fisiologia , Estágios do Ciclo de Vida , Masculino , Infecções por Protozoários/parasitologia , Infecções por Protozoários/transmissão
17.
Plant Physiol ; 185(4): 1764-1782, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33793935

RESUMO

In monocots other than maize (Zea mays) and rice (Oryza sativa), the repertoire and diversity of microRNAs (miRNAs) and the populations of phased, secondary, small interfering RNAs (phasiRNAs) are poorly characterized. To remedy this, we sequenced small RNAs (sRNA) from vegetative and dissected inflorescence tissue in 28 phylogenetically diverse monocots and from several early-diverging angiosperm lineages, as well as publicly available data from 10 additional monocot species. We annotated miRNAs, small interfering RNAs (siRNAs) and phasiRNAs across the monocot phylogeny, identifying miRNAs apparently lost or gained in the grasses relative to other monocot families, as well as a number of transfer RNA fragments misannotated as miRNAs. Using our miRNA database cleaned of these misannotations, we identified conservation at the 8th, 9th, 19th, and 3'-end positions that we hypothesize are signatures of selection for processing, targeting, or Argonaute sorting. We show that 21-nucleotide (nt) reproductive phasiRNAs are far more numerous in grass genomes than other monocots. Based on sequenced monocot genomes and transcriptomes, DICER-LIKE5, important to 24-nt phasiRNA biogenesis, likely originated via gene duplication before the diversification of the grasses. This curated database of phylogenetically diverse monocot miRNAs, siRNAs, and phasiRNAs represents a large collection of data that should facilitate continued exploration of sRNA diversification in flowering plants.


Assuntos
Inflorescência/genética , Magnoliopsida/crescimento & desenvolvimento , Magnoliopsida/genética , RNA de Plantas , Reprodução/genética , Reprodução/fisiologia , Regulação da Expressão Gênica de Plantas , Variação Genética , Genótipo , Inflorescência/fisiologia , MicroRNAs , Análise de Sequência de RNA
18.
Zoo Biol ; 40(4): 273-279, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33848361

RESUMO

Vancouver Island marmots (Marmota vancouverensis) have been managed in a captive-breeding program since 1997, as in situ conservation efforts were insufficient in raising the numbers of this critically endangered species. The success of captive-breeding programs centers on sustainable reproduction and survival of individuals once released into the wild. Captive-born Vancouver Island marmots released to the wild have lower survival rates than their wild-born counterparts; this difference may arise from compromised hibernation patterns or behaviors. Hibernation duration, body weight over the hibernation season, and reproductive success of captive Vancouver Island marmots were reviewed to assess the effect of these variables on each other. Data from a total of 1782 hibernations and 456 breeding attempts were compiled from 1997 to 2018. The number of winters spent in captivity, the origin of the marmot (captive-born or wild-born), the facility at which hibernation occurred, and the body weight all had a significant effect on hibernation length (all p < .001). Increased weight was associated with increased hibernation length by 0.4 ± 0.1 day/kg on average (p = .0015). Captive, wild-born marmots hibernated for significantly longer than their captive-born counterparts by about 21 ± 2 days (p < .001). The odds of successful breeding were significantly increased with increasing hibernation length by approximatively 20% for every 10 additional days of hibernation. This study provides information on the intrinsic relationship between body weight, reproduction, and hibernation in captive Vancouver Island marmots.


Assuntos
Criação de Animais Domésticos , Animais de Zoológico , Hibernação/fisiologia , Marmota/fisiologia , Reprodução/fisiologia , Animais , Feminino , Masculino , Estudos Retrospectivos
19.
Zoo Biol ; 40(4): 320-329, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33861886

RESUMO

A fifth of all known species are currently classified as threatened in the wild: the rate of biodiversity loss is rapid, continuous, and mostly due to anthropogenic activities. To slow down this decline, the accurate estimation of demographic parameters for threatened species is critical. With this aim, zoo institutions play an important role, giving access to data on zoo-housed animals, which aids researchers working on species life-history traits and intrinsic factors influencing the fitness of both sexes, such as age. While tigers (Panthera tigris) are particularly threatened in their natural environment, few of their demographic parameters have been determined because of their solitary and elusive nature as well as low population density. Using individual-based information for more than 9200 tigers (from 1938 to 2018) recorded in the International Tiger Studbook 2018, we aimed to determine sub-species and sex-specific variability of survival and reproductive parameters with age. No significant sex-difference in actuarial senescence (i.e., decline of survival probabilities with age) was observed but males tended to have a higher juvenile mortality and a faster senescence than females. Reproductive senescence (i.e., decline of reproductive parameters with age) was more pronounced in females than males. Moreover, we observed sub-species-specific variation in mortality and reproductive patterns, pointing out the necessity to consider them independently for conservation goals. Our findings can provide meaningful improvements to the husbandry of zoo-housed tigers, emphasizing the importance of adult breeding females of 7-9 years-old to control zoo-housed population size, but also providing accurate demographic estimates, crucial to set up effective conservation plans.


Assuntos
Envelhecimento , Animais de Zoológico , Conservação dos Recursos Naturais , Reprodução/fisiologia , Tigres/genética , Tigres/fisiologia , Animais , Espécies em Perigo de Extinção , Feminino , Masculino , Especificidade da Espécie
20.
Int J Mol Sci ; 22(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806348

RESUMO

There is substantial genetic variation for common traits associated with reproductive lifespan and for common diseases influencing female fertility. Progress in high-throughput sequencing and genome-wide association studies (GWAS) have transformed our understanding of common genetic risk factors for complex traits and diseases influencing reproductive lifespan and fertility. The data emerging from GWAS demonstrate the utility of genetics to explain epidemiological observations, revealing shared biological pathways linking puberty timing, fertility, reproductive ageing and health outcomes. The observations also identify unique genetic risk factors specific to different reproductive diseases impacting on female fertility. Sequencing in patients with primary ovarian insufficiency (POI) have identified mutations in a large number of genes while GWAS have revealed shared genetic risk factors for POI and ovarian ageing. Studies on age at menopause implicate DNA damage/repair genes with implications for follicle health and ageing. In addition to the discovery of individual genes and pathways, the increasingly powerful studies on common genetic risk factors help interpret the underlying relationships and direction of causation in the regulation of reproductive lifespan, fertility and related traits.


Assuntos
Fertilidade/genética , Reprodução/genética , Envelhecimento/genética , Envelhecimento/fisiologia , Feminino , Fertilidade/fisiologia , Hormônio Foliculoestimulante Humano/genética , Hormônio Foliculoestimulante Humano/fisiologia , Variação Genética , Estudo de Associação Genômica Ampla , Humanos , Longevidade/genética , Longevidade/fisiologia , Hormônio Luteinizante/genética , Hormônio Luteinizante/fisiologia , Menopausa/genética , Menopausa/fisiologia , Polimorfismo de Nucleotídeo Único , Reprodução/fisiologia , Fatores de Risco
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