RESUMEN
Insect pest control can be achieved by the application of RNA interference (RNAi), a key molecular tool in functional genomics. Whereas most RNAi research has focused on insect pests, few studies have been performed on natural enemies. Validating the efficacy of RNAi in natural enemies is crucial for assessing its safety and enabling molecular research on these organisms. Here, we assessed the efficacy of RNAi in the ladybird beetle Eriopis connexa Germar (Coleoptera: Coccinellidae), focusing on genes related to reproduction, such as vitellogenin (Vg) and its receptor (VgR). In the transcriptome of E. connexa, we found one VgR (EcVgR) and two Vg genes (EcVg1 and EcVg2). These genes have been validated by in silico analyses of functional domains and evolutionary relationships. Five-day-old females were injected with 500 ng/µL of a specific double-stranded RNA (dsRNA) (dsEcVg1, dsEcVg2, or dsEcVgR) for RNAi tests, while nonspecific dsRNA (dsGFP or dsAgCE8.1) was used as a control. Interestingly, dsEcVg2 was able to knockdown both Vg genes, while dsEcVg1 could silence only EcVg1. Additionally, the viability of the eggs was significantly reduced when both Vg genes were knocked down at the same time (after treatment with dsEcVg2 or "dsEcVg1+dsEcVg2"). Ultimately, malformed, nonviable eggs were produced when EcVgR was silenced. Interestingly, no dsRNA treatment had an impact on the quantity of eggs laid. Therefore, the feasibility of RNAi in E. connexa has been confirmed, suggesting that this coccinellid is an excellent Neotropical model for molecular research on natural enemies and for studying RNAi nontarget effects.
Asunto(s)
Escarabajos , Técnicas de Silenciamiento del Gen , Interferencia de ARN , Animales , Escarabajos/genética , Femenino , Vitelogeninas/genética , Vitelogeninas/metabolismo , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Reproducción/genética , ARN Bicatenario/genética , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Proteínas del Huevo/genética , Proteínas del Huevo/metabolismo , Control Biológico de VectoresRESUMEN
Energy metabolism is essential for insect development, reproduction and detoxification. Insects often reallocate energy and resources to manage external stress, balancing the demands of detoxification and reproduction. Glucose transport 4 (Glut4), a glucose transporter, is involved in glucose and lipid metabolism. However, the specific molecular mechanism of Glut4 in insect reproduction, and its role in the response to insecticide-induced oxidative stress remain unclear. In this study, LmGlut4 was identified and analyzed in Locusta migratoria. Silencing of LmGlut4 significantly reduced vitellogenin (Vg) biosynthesis in the fat body and Vg absorption by oocytes, ultimately hindering ovarian development and oocyte maturation. Knockdown of LmGlut4 also inhibited the biosynthesis of key insect hormones, such as juvenile hormone (JH), 20-hydroxyecdysone (20E) and insulin. Furthermore, LmGlut4 knockdown led to reduced triglyceride (TG) and glycogen content in the fat body and ovary, as well as decreased capacity for trehalose biosynthesis in adipocytes. Additionally, dsLmGlut4-treated locusts showed heightened sensitivity to deltamethrin, leading to increased triglyceride depletion during detoxification. This study sheds light on the biological function of LmGlut4 in the ovary and provides potential target genes for exploring biological pest management strategies.
Asunto(s)
Transportador de Glucosa de Tipo 4 , Insecticidas , Locusta migratoria , Nitrilos , Ovario , Piretrinas , Interferencia de ARN , Animales , Piretrinas/farmacología , Femenino , Nitrilos/farmacología , Ovario/metabolismo , Ovario/efectos de los fármacos , Transportador de Glucosa de Tipo 4/metabolismo , Transportador de Glucosa de Tipo 4/genética , Locusta migratoria/genética , Locusta migratoria/efectos de los fármacos , Locusta migratoria/metabolismo , Insecticidas/farmacología , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Vitelogeninas/metabolismo , Vitelogeninas/genética , Metabolismo Energético/efectos de los fármacos , Cuerpo Adiposo/metabolismo , Cuerpo Adiposo/efectos de los fármacos , Hormonas Juveniles/metabolismo , Hormonas Juveniles/farmacología , Oocitos/metabolismo , Oocitos/efectos de los fármacos , Triglicéridos/metabolismoRESUMEN
Nanoplastics (NPs) have been commonly detected in aquatic ecosystems, and their negative effects on aquatic organisms have raised concerns in the scientific community and general public. The acute toxicity, neurotoxicity, and metabolic toxicity induced by NPs on fishes have been reported by many studies, although less attention has been focused on how mother exposed to NPs affected their offspring in aquatic organisms. Here, female zebrafish (F0) were exposed to 0, 200 and 2000 µg/L polystyrene nanoplastics (PS-NPs) for 42 d, with their offspring (F1) reared in clear water until sexual maturity. The results showed that PS-NPs were detected in various organs of F0 and F1. PS-NPs exposure significantly decreased gonadal 17-estradiol (E2), while increasing testosterone (T) contents. Lower levels of cyp19a1a, lhr and erα expressions in the 2000 µg/L group were consistent with a reduced number of mature oocytes (MO), but an increase in perinucleolar oocytes (PO). Interestingly, the expression of vtg was only up-regulated by 200 µg/L PS-NPs. After exposure, the egg production was dramatically reduced, but the hatching rate and heartbeat of F1 embryos from treated females were significantly higher than those observed in females from the control group. Maternal PS-NPs exposure significantly decreased the E2 and T levels in F1 adults, while PS-NPs exposure significantly up-regulated the sox9a but down-regulated the foxl2a in F1 larvae of 30 days post fertilization (dpf). This study showed that PS-NPs caused reproductive toxicity by changing the hypothalamic-pituitary-gonadal (HPG) axis-related genes, impairing the reproductive capacity of female zebrafish, affecting the development and disrupting the endocrine function of F1. These results suggested that PS-NPs had adverse effects on fish reproductive system both in the directly exposed generation and in their unexposed offspring.
Asunto(s)
Poliestirenos , Reproducción , Contaminantes Químicos del Agua , Pez Cebra , Animales , Femenino , Contaminantes Químicos del Agua/toxicidad , Poliestirenos/toxicidad , Reproducción/efectos de los fármacos , Estradiol , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Testosterona/metabolismo , Nanopartículas/toxicidad , Embrión no Mamífero/efectos de los fármacos , Exposición Materna , Vitelogeninas/metabolismo , Oocitos/efectos de los fármacosRESUMEN
To enhance our understanding of teleost reproductive physiology, we identified six Sichuan bream (Sinibrama taeniatus) vitellogenin genes (vtg1-6) and characterized their sequence structures. We categorized them into type â (vtg1,4,5 and 6), type â ¡ (vtg2) and type â ¢ (vtg3) based on differences in their subdomain structure. The promoter sequence of vtgs has multiple estrogen response elements, and their abundance appears to correlate with the responsiveness of vtg gene expression to estrogen. Gene expression analyses revealed that the vitellogenesis of Sichuan bream involves both heterosynthesis and autosynthesis pathways, with the dominant pathway originating from the liver. The drug treatment experiments revealed that 17ß-estradiol (E2) tightly regulated the level of vtg mRNA in the liver. Feeding fish with a diet containing 100 µg/g E2 for three weeks significantly induced vtg gene expression and ovarian development, leading to an earlier onset of vitellogenesis. Additionally, it was observed that the initiation of vtg transcription required E2 binding to its receptor, a process primarily mediated by estrogen receptor alpha in Sichuan bream. The findings of this study provide novel insights into the molecular information of the vitellogenin gene family in teleosts, thereby contributing to the regulation of gonadal development in farmed fish.
Asunto(s)
Estrógenos , Vitelogeninas , Animales , Vitelogeninas/genética , Vitelogeninas/metabolismo , Estrógenos/metabolismo , Estrógenos/farmacología , Vitelogénesis/genética , Estradiol/farmacología , Estradiol/metabolismo , Regiones Promotoras Genéticas , Femenino , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Filogenia , Regulación de la Expresión Génica/efectos de los fármacos , Familia de Multigenes , Hígado/metabolismo , Genoma , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismoRESUMEN
Nodularin is a potent cyanotoxin that has been detected in aquatic environments as well as in the body of aquatic organisms throughout the world, but its effects on the reproductive system are yet to be explored. The present study investigated the toxic effects of environmentally relevant concentrations of nodularin on the reproductive endocrine system of female zebrafish (Danio rerio). After exposure to nodularin for 14 days, decreased gonadosomatic Index (GSI), germinal vesicle breakdown (GVBD), and decreased level of follicle-stimulating hormone (FSH), luteinizing hormone (LH), 17ß-estradiol (E2) level and increased testosterone (T) content in female zebrafish suggested that nodularin may disrupt both oocyte growth and maturation. In support of this data, alteration in different marker gene expression on the hypothalamic-pituitary-gonadal-liver (HPGL) axis was observed. Transcriptional levels of genes related to steroidogenesis including cytochrome P450 aromatase (cyp19a1a) in the ovary and primary vitellogenin genes (vtg1, vtg2, and vtg3) in the liver were down-regulated and marker genes for oxidative stress (sod, cat, and gpx) were up-regulated on HPGL axis. These findings revealed for the first time that nodularin is a potent endocrine-disrupting compound posing oxidative stress and causes reproductive endocrine toxicity in female zebrafish, emphasizing the importance of assessing its environmental risks.
Asunto(s)
Ovario , Contaminantes Químicos del Agua , Pez Cebra , Animales , Pez Cebra/fisiología , Femenino , Contaminantes Químicos del Agua/toxicidad , Ovario/efectos de los fármacos , Vitelogeninas/genética , Vitelogeninas/metabolismo , Sistema Endocrino/efectos de los fármacos , Estradiol , Disruptores Endocrinos/toxicidad , Reproducción/efectos de los fármacos , Hígado/efectos de los fármacos , Testosterona , Estrés Oxidativo/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Hormona Folículo Estimulante , Hormona LuteinizanteRESUMEN
The extensive use of herbicide metamifop (MET) in rice fields for weeds control will inevitably lead to its entering into water environments and threaten the aquatic organisms. Previous researches have demonstrated that sublethal exposure of MET significantly affected zebrafish development. Yet the long-term toxicological impacts of MET on aquatic life remains unknown. Herein, we investigated the potential effects of MET (5 and 50 µg/L) on zebrafish during an entire life cycle. Since the expression level of male sex differentiation-related gene dmrt1 and sex hormone synthesis-related gene cyp19a1b were significantly changed after 50 µg/L MET exposure for only 7 days, indicators related to sex differentiation and reproductive system were further investigated. Results showed that the transcript of dmrt1 was inhibited, estradiol content increased and testosterone content decreased in zebrafish of both sexes after MET exposure at 45, 60 and 120 dpf. Histopathological sections showed that the proportions of mature germ cells in the gonads of male and female zebrafish (120 dpf) were significantly decreased. Moreover, males had elevated vitellogenin content while females did not after MET exposure; MET induced feminization in zebrafish, with the proportion of females significantly increased by 19.6% while that of males significantly decreased by 13.2% at 120 dpf. These results suggested that MET interfered with the expression levels of gonad development related-genes, disrupted sex hormone balance, and affected sex differentiation and reproductive system of female and male zebrafish, implying it might have potential endocrine disrupting effects after long-term exposure.
Asunto(s)
Diferenciación Sexual , Vitelogeninas , Contaminantes Químicos del Agua , Pez Cebra , Animales , Diferenciación Sexual/efectos de los fármacos , Masculino , Femenino , Contaminantes Químicos del Agua/toxicidad , Vitelogeninas/metabolismo , Vitelogeninas/genética , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Herbicidas/toxicidad , Aromatasa/genética , Aromatasa/metabolismo , Estradiol , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Testosterona , Gónadas/efectos de los fármacos , Reproducción/efectos de los fármacosRESUMEN
This study aimed to investigate the toxicity and endocrine disrupting potential of a complex mixture of polycyclic aromatic hydrocarbons (PAHs) in the estrogen pathway using hepatocytes of Nile tilapia Oreochromis niloticus, the hepatocytes were exposed to various concentrations of the PAH mixture, and multiple endpoints were evaluated to assess their effects on cell viability, gene expression, oxidative stress markers, and efflux activity. The results revealed that the PAH mixture had limited effects on hepatocyte metabolism and cell adhesion, as indicated by the non-significant changes observed in MTT metabolism, neutral red retention, and crystal violet staining. However, significant alterations were observed in the expression of genes related to the estrogen pathway. Specifically, vitellogenin (vtg) exhibited a substantial increase of approximately 120% compared to the control group. Similarly, estrogen receptor 2 (esr2) showed a significant upregulation of approximately 90%. In contrast, no significant differences were observed in the expression of estrogen receptor 1 (esr1) and the G protein-coupled estrogen receptor 1 (gper1). Furthermore, the PAH mixture elicited complex responses in oxidative stress markers. While reactive oxygen species (ROS) and reactive nitrogen species (RNS) levels remained unchanged, the activity of catalase (Cat) was significantly reduced, whereas superoxide dismutase (Sod) activity, glutathione S-transferase (Gst) activity, and non-protein thiols levels were significantly elevated. In addition, the PAH mixture significantly influenced efflux activity, as evidenced by the increased efflux of rhodamine and calcein, indicating alterations in multixenobiotic resistance (MXR)-associated proteins. Overall, these findings, associated with bioinformatic analysis, highlight the potential of the PAH mixture to modulate the estrogen pathway and induce oxidative stress in O. niloticus hepatocytes. Understanding the mechanisms underlying these effects is crucial for assessing the ecological risks of PAH exposure and developing appropriate strategies to mitigate their adverse impacts on aquatic organisms.
Asunto(s)
Cíclidos , Disruptores Endocrinos , Estrógenos , Hepatocitos , Estrés Oxidativo , Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Animales , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Cíclidos/metabolismo , Cíclidos/genética , Contaminantes Químicos del Agua/toxicidad , Disruptores Endocrinos/toxicidad , Hidrocarburos Policíclicos Aromáticos/toxicidad , Estrés Oxidativo/efectos de los fármacos , Estrógenos/toxicidad , Supervivencia Celular/efectos de los fármacos , Vitelogeninas/metabolismo , Vitelogeninas/genética , Especies Reactivas de Oxígeno/metabolismoRESUMEN
The water accommodated fraction (WAF) of spilled crude oil is a severe threat to the health of marine fish. This study was conducted to investigate the effects of short-term embryonic exposure to the WAF on the ovarian development and reproductive capability of F0 adult female marine medaka (Oryzias melastigma). Following embryonic exposure to the WAF with nominal total petroleum hydrocarbon concentrations of 0.5, 5, 50, and 500 µg/L for 7 days, the number of spawned eggs and gonadosomatic indices of F0 adult females were significantly reduced at 130 days postfertilization. In these F0 adult females, the proportion of mature oocytes was significantly lower, the level of 17ß-estradiol was lower, and the level of testosterone was greater than those in control group. The mRNA levels of the follicle-stimulating hormone ß subunit, luteinizing hormone ß subunit, cytochrome P450 aromatase 19b, estrogen receptor α and ß, and androgen receptor α and ß genes were upregulated, while the mRNA level of the salmon-type gonadotropin-releasing hormone was downregulated in F0 adult females exposed to the WAF during the embryonic stage. Additionally, the methylation level of vitellogenin (vtg) in F0 adult females was significantly elevated, this might have, in turn, downregulated the mRNA level of vtg. The mortality rate of the unexposed F1 embryos was significantly increased and the hatching success was significantly reduced. These results collectively indicated the necessity of incorporating and evaluating the effects of short-term early-life exposure to crude oil in the assessment of risks to the reproductive health of marine fish.
Asunto(s)
Oryzias , Petróleo , Reproducción , Vitelogeninas , Contaminantes Químicos del Agua , Animales , Femenino , Oryzias/fisiología , Contaminantes Químicos del Agua/toxicidad , Petróleo/toxicidad , Reproducción/efectos de los fármacos , Vitelogeninas/metabolismo , Vitelogeninas/genética , Estradiol , Embrión no Mamífero/efectos de los fármacos , Contaminación por Petróleo , Aromatasa/metabolismo , Aromatasa/genética , Ovario/efectos de los fármacos , Testosterona/metabolismoRESUMEN
Numerous pharmaceutical and industrial chemicals are classified as endocrine-disrupting chemicals (EDCs) that interfere with hormonal homeostasis, leading to developmental disorders and other pathologies. The synthetic estrogen 17α-ethynylestradiol (EE2) is used in oral contraceptives and other hormone therapies. EE2 and other estrogens are inadvertently introduced into aquatic environments through municipal wastewater and agricultural effluents. Exposure of male fish to estrogens increases expression of the egg yolk precursor protein vitellogenin (Vtg), which is used as a molecular marker of exposure to estrogenic EDCs. The mechanisms behind Vtg induction are not fully known, and we hypothesized that it is regulated via DNA methylation. Adult zebrafish were exposed to either dimethyl sulfoxide or 20 ng/L EE2 for 14 days. Messenger RNA (mRNA) expression and DNA methylation were assessed in male zebrafish livers at 0, 0.25, 0.5, 1, 4, 7, and 14 days of exposure; and those of females were assessed at 13 days (n ≥ 4/group/time point). To test the persistence of any changes, we included a recovery group that received EE2 for 7 days and did not receive any for the following 7 days, in the total 14-day study. Methylation of DNA at the vtg1 promoter was assessed with targeted gene bisulfite sequencing in livers of adult male and female zebrafish. A significant increase in vtg1 mRNA was observed in the EE2-exposed male fish as early as 6 h. Interestingly, DNA methylation changes were observed at 4 days. Decreases in the overall methylation of the vtg1 promoter in exposed males resulted in levels comparable to those in female controls, suggesting feminization. Importantly, DNA methylation levels in males remained significantly impacted after 7 days post-EE2 removal, unlike mRNA levels. These data identify an epigenetic mark of feminization that may serve as an indicator of not only estrogenic exposure but also previous exposure to EE2. Environ Toxicol Chem 2024;43:1547-1556. © 2024 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.
Asunto(s)
Islas de CpG , Metilación de ADN , Etinilestradiol , Regiones Promotoras Genéticas , Vitelogeninas , Contaminantes Químicos del Agua , Pez Cebra , Animales , Pez Cebra/genética , Masculino , Etinilestradiol/toxicidad , Metilación de ADN/efectos de los fármacos , Vitelogeninas/genética , Vitelogeninas/metabolismo , Femenino , Contaminantes Químicos del Agua/toxicidad , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Disruptores Endocrinos/toxicidadRESUMEN
The vitellogenin receptor (VgR) is essential for the uptake and transport of the yolk precursor, vitellogenin (Vg). Vg is synthesized in the fat body, released in the hemolymph, and absorbed in the ovaries, via receptor-mediated endocytosis. Besides its important role in the reproductive pathway, Vg occurs in nonreproductive worker honey bee, suggesting its participation in other pathways. The objective was to verify if the VgR occurs in the hypopharyngeal glands of Apis mellifera workers and how Vg is internalized by these cells. VgR occurrence in the hypopharyngeal glands was evaluated by qPCR analyses of VgR and immunohistochemistry in workers with different tasks. The VgR gene is expressed in the hypopharyngeal glands of workers with higher transcript levels in nurse honey bees. VgR is more expressed in 11-day-old workers from queenright colonies, compared to orphan ones. Nurse workers with developed hypopharyngeal glands present higher VgR transcripts than those with poorly developed glands. The immunohistochemistry results showed the co-localization of Vg, VgR and clathrin (protein that plays a major role in the formation of coated vesicles in endocytosis) in the hypopharyngeal glands, suggesting receptor-mediated endocytosis. The results demonstrate that VgR performs the transport of Vg to the hypopharyngeal glands, supporting the Ovary Ground Plan Hypothesis and contributing to the understanding of the role of this gland in the social context of honey bees.
Asunto(s)
Proteínas del Huevo , Hipofaringe , Proteínas de Insectos , Receptores de Superficie Celular , Animales , Abejas/metabolismo , Abejas/genética , Receptores de Superficie Celular/metabolismo , Receptores de Superficie Celular/genética , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Proteínas del Huevo/metabolismo , Proteínas del Huevo/genética , Hipofaringe/metabolismo , Femenino , Vitelogeninas/metabolismo , Vitelogeninas/genética , Clatrina/metabolismoRESUMEN
Tick infestations transmit various infectious agents and result in significant socioeconomic consequences. Currently, the primary focus of tick control efforts is identifying potential targets for immune intervention. In a previous study, we identified a highly conserved protein abundant in tick haemolymph extracellular vesicles (EVs) known as translationally controlled tumour protein (TCTP). We have found that native TCTP is present in various tissues of the Rhipicephalus haemaphysaloides tick, including salivary glands, midgut, ovary, and fat body. Notably, TCTP is particularly abundant in the tick ovary and its levels increase progressively from the blood-feeding stage to engorgement. When the TCTP gene was knocked down by RNAi, there was a noticeable delay in ovarian development, and the reproductive performance, in terms of egg quantity and survival, was also hindered. Our investigations have revealed that the observed effects in ovary and eggs in dsRNA-treated ticks are not attributable to cell death mechanisms like apoptosis and autophagy but rather to the reduction in the expression of vitellogenin (Vg1, Vg2, and Vg3) and ferritin (ferritin 1 and ferritin 2) proteins crucial for ovarian development and embryo survival in ticks. Additionally, phylogenetic analysis and structural comparisons of RhTCTP and its orthologues across various tick species, vertebrate hosts, and humans have shown that TCTP is conserved in ticks but differs significantly between ticks and their hosts, particularly in the TCTP_1 and TCTP_2 domains. Overall, TCTP plays a vital role in tick reproductive development and presents itself as a potential target for tick control in both humans and animals.
Asunto(s)
Ovario , Oviposición , Rhipicephalus , Proteína Tumoral Controlada Traslacionalmente 1 , Animales , Femenino , Rhipicephalus/genética , Rhipicephalus/fisiología , Rhipicephalus/crecimiento & desarrollo , Filogenia , Vitelogeninas/genética , Vitelogeninas/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismoRESUMEN
Peroxisomes are ubiquitous cellular organelles participating in a variety of critical metabolic reactions. PEX14 is an essential peroxin responsible for peroxisome biogenesis. In this study, we identified the human PEX14 homolog in the brown planthopper, Nilaparvata lugens (Hemiptera: Delphacidae). N. lugens PEX14 (NlPEX14) showed significant topological similarity to its human counterpart. It is expressed throughout all developmental stages, with the highest expression observed in adult insects. Down-regulation of NlPEX14 through injection of NlPEX14-specific double-strand RNA impaired nymphal development. Moreover, females subjected to dsNlPEX14 treatment exhibited a significantly reduced lifespan. Additionally, we found abnormal ovarian development and a significant decrease in the number of eggs laid in NlPEX14-downregulated females. Further experiments support that the shortening of lifespan and the decrease in female fecundity can be attributed, at least partially, to the accumulation of fatty acids and reduced expression of vitellogenin. Together, our study reveals an indispensable function of NlPEX14 for insect reproduction and establishes a causal connection between the phenotypes and peroxisome biogenesis, shedding light on the importance of peroxisomes in female fecundity.
Asunto(s)
Fertilidad , Hemípteros , Proteínas de Insectos , Animales , Hemípteros/genética , Hemípteros/metabolismo , Hemípteros/fisiología , Hemípteros/crecimiento & desarrollo , Femenino , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Peroxisomas/metabolismo , Longevidad , Ninfa/crecimiento & desarrollo , Ninfa/metabolismo , Ninfa/genética , Peroxinas/metabolismo , Peroxinas/genética , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Vitelogeninas/metabolismo , Vitelogeninas/genéticaRESUMEN
Alkylphenols, such as nonylphenol and 4-tert-octylphenol (OP), are byproducts of the biodegradation of alkylphenol ethoxylates and present substantial ecological and health risks in aquatic environments and higher life forms. In this context, our study aimed to explore the effect of OP on reproductive endocrine function in both female and male zebrafish. Over a period of 21 days, the zebrafish were subjected to varying concentrations of OP (0, 0.02, 0.1, and 0.5⯵g/L), based on the lowest effective concentration (EC10 = 0.48⯵g/L) identified for zebrafish embryos. OP exposure led to a pronounced increase in hepatic vitellogenin (vtg) mRNA expression and 17ß-estradiol biosynthesis in both sexes. Conversely, OP exhibits anti-androgenic properties, significantly diminishes gonadal androgen receptor (ar) mRNA expression, and reduces endogenous androgen (testosterone and 11-ketotestosterone) levels in male zebrafish. Notably, cortisol and thyroid hormone (TH) levels demonstrated concentration-dependent elevations in zebrafish, influencing the regulation of gonadal steroid hormones (GSHs). These findings suggest that prolonged OP exposure may result in sustained reproductive dysfunction in adult zebrafish, which is largely attributable to the intricate reciprocal relationship between hormone levels and the associated gene expression. Our comprehensive biological response analysis of adult zebrafish offers vital insights into the reproductive toxicological effects of OP, thereby enriching future ecological studies on aquatic systems.
Asunto(s)
Disruptores Endocrinos , Estrógenos , Fenoles , Receptores Androgénicos , Hormonas Tiroideas , Vitelogeninas , Contaminantes Químicos del Agua , Pez Cebra , Animales , Fenoles/toxicidad , Masculino , Contaminantes Químicos del Agua/toxicidad , Femenino , Vitelogeninas/metabolismo , Disruptores Endocrinos/toxicidad , Hormonas Tiroideas/metabolismo , Receptores Androgénicos/metabolismo , Receptores Androgénicos/genética , Estrógenos/toxicidad , Estradiol/toxicidad , Antagonistas de Andrógenos/toxicidad , Testosterona/metabolismo , Testosterona/análogos & derivados , HidrocortisonaRESUMEN
Combined oral contraceptives, comprising of both an oestrogen and a progestin component, are released in aquatic environments and potentially pose a risk to aquatic wildlife by their capacity to disrupt physiological mechanisms. In this study, the endocrine disruptive potential of two mixtures, 17α-ethinylestradiol (EE2), a synthetic oestrogen, or estetrol (E4), a natural oestrogen, with the progestin drospirenone (DRSP) have been characterised in three generations of zebrafish, according to an adapted Medaka Extended One Generation Reproduction Test. Zebrafish (Danio rerio) were exposed to a range of concentrations of EE2/DRSP and E4/DRSP (â¼1×, â¼3×, â¼10× and â¼30× predicted environmental concentration, PEC). Survival, growth, hatching success, fecundity, fertilisation success, vitellogenin (VTG), gonad histopathology, sex differentiation, and transcriptional analysis of genes related to gonadal sex steroid hormones synthesis were assessed. In the F0 generation, exposure to EE2/DRSP at â¼10 and â¼30× PEC decreased fecundity and increased male VTG concentrations. The highest concentration of EE2/DRSP also affected VTG concentrations in female zebrafish and the expression of genes implicated in steroid hormones synthesis. In the F1 generation, sex determination was impaired in fish exposed to EE2/DRSP at concentrations as low as â¼3× PEC. Decreased fecundity and fertility, and abnormal gonadal histopathology were also observed. No effects were observed in the F2 generation. In contrast, E4/DRSP induced only minor histopathological changes and an increase in the proportion of males, at the highest concentration tested (â¼30× PEC) in the F1 generation and had no effect on hatching success of F2 generation. Overall, this study suggests that the combination E4/DRSP has a more favourable environmental profile than EE2/DRSP.
Asunto(s)
Androstenos , Disruptores Endocrinos , Etinilestradiol , Pez Cebra , Animales , Pez Cebra/fisiología , Etinilestradiol/toxicidad , Androstenos/toxicidad , Disruptores Endocrinos/toxicidad , Femenino , Masculino , Contaminantes Químicos del Agua/toxicidad , Vitelogeninas/metabolismo , Reproducción/efectos de los fármacosRESUMEN
In oviparous animals, egg yolk is largely derived from vitellogenin, which is taken up from the maternal circulation by the growing oocytes via the vitellogenin receptor. Recently, a novel member of the lipoprotein receptor superfamily termed low-density lipoprotein receptor-related protein 13 was identified and proposed as a candidate of vitellogenin receptor in oviparous animals. However, the roles of low-density lipoprotein receptor-related protein 13 in vitellogenesis are still poorly defined. Here, we investigated the expression, vitellogenin-binding properties, and function of low-density lipoprotein receptor-related protein 13 in zebrafish. Two different lrp13 genes termed lrp13a and lrp13b were found in zebrafish. Reverse transcription polymerase chain reaction and quantitative polymerase chain reaction revealed both lrp13s to be predominantly expressed in zebrafish ovary, and in situ hybridization detected both lrp13s transcripts in the ooplasm of early stage oocytes. Two yeast hybrid studies showed that among eight vitellogenins of zebrafish, Vtg1, 2, and 3 bind to Lrp13a, while Vtg1, 2, and 5 bind to Lrp13b. We created zebrafish lrp13a and lrp13b mutant lines using CRISPR/Cas9. Knockout of lrp13a leads to a male-biased sex ratio and decreased diameter of embryo yolk, while knockout of lrp13b and double knockout of lrp13a and lrp13b leads to the delay of vitellogenesis, followed by follicular atresia. These phenotypes of mutants can be explained by the disruption of vitellogenesis in the absence of Lrp13s. Taken together, our results indicate that both Lrp13a and Lrp13b can serve as vitellogenin receptors in zebrafish among other vitellogenin receptors that are not yet described.
Asunto(s)
Proteínas del Huevo , Ovario , Vitelogeninas , Proteínas de Pez Cebra , Pez Cebra , Animales , Femenino , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Ovario/metabolismo , Vitelogeninas/metabolismo , Vitelogeninas/genética , Proteínas del Huevo/metabolismo , Proteínas del Huevo/genética , Receptores de Superficie Celular/metabolismo , Receptores de Superficie Celular/genéticaRESUMEN
To investigate the alterations of yolk protein during embryonic development in Wanxi white goose, the egg yolk protein composition at days 0, 4, 7, 14, 18, and 25 of incubation (D0, D4, D7, D14, D18, and D25) was analyzed by two-dimensional gel electrophoresis combined with mass spectrometry. A total of 65 spots representing 11 proteins with significant abundance changes were detected. Apolipoprotein B-100, vitellogenin-1, vitellogenin-2-like, riboflavin-binding protein, and serotransferrin mainly participated in nutrient (lipid, riboflavin, and iron ion) transport, and vitellogenin-2-like showed a lower abundance after D14. Ovomucoid-like were involved in endopeptidase inhibitory activity and immunoglobulin binding and exhibited a higher expression after D18, suggesting a potential role in promoting the absorption of immunoglobulin and providing passive immune protection for goose embryos after D18. Furthermore, myosin-9 and actin (ACTB) were involved in the tight junction pathway, potentially contributing to barrier integrity. Serum albumin mainly participated in cytolysis and toxic substance binding. Therefore, the high expression of serum albumin, myosin-9, and ACTB throughout the incubation might protect the developing embryo. Apolipoprotein B-100, vitellogenin-1, vitellogenin-2-like, riboflavin-binding protein, and serotransferrin might play a crucial role in providing nutrition for embryonic development, and VTG-2-like was preferentially degraded/absorbed.
Asunto(s)
Gansos , Vitelogeninas , Animales , Vitelogeninas/análisis , Gansos/metabolismo , Apolipoproteína B-100/análisis , Apolipoproteína B-100/metabolismo , Proteómica , Transferrina , Proteínas del Huevo/química , Desarrollo Embrionario , Albúmina Sérica/metabolismo , Inmunoglobulinas/análisis , Miosinas/análisis , Miosinas/metabolismo , Yema de Huevo/químicaRESUMEN
Natural and synthetic environmental estrogens (EEs) are widespread and have received extensive attention. Our previous studies demonstrated that depletion of the cytochrome P450 17a1 gene (cyp17a1) leads to all-testis differentiation phenotype in zebrafish and common carp. In the present study, cyp17a1-deficient zebrafish with defective estrogen biosynthesis were used for the evaluation of EEs, as assessed by monitoring vitellogenin (vtg) expression. A rapid and sensitive assessment procedure was established with the 3-day administration of estradiol (E2), followed by examination of the transcriptional expression of vtgs in our cyp17a1-deficient fish. Compared with the control fish, a higher E2-mediated vtg upregulation observed in cyp17a1-deficient zebrafish exposed to 0.1 µg/L E2 is known to be estrogen receptor-dependent and likely due to impaired in vivo estrogen biosynthesis. The more responsive vtg expression in cyp17a1-deficient zebrafish was observed when exposed to 200 and 2000 µg/L bisphenol A (BPA) and perfluoro-1-octanesulfonate (PFOS). The estrogenic potentials of E2, BPA, and PFOS were compared and assessed by the feminization effect on ovarian differentiation in cyp17a1-deficient zebrafish from 18 to 50 days postfertilization, based on which a higher sensitivity of E2 in ovarian differentiation than BPA and PFOS was concluded. Collectively, through the higher sensitivity to EEs and the capacity to distinguish chemicals with different estrogenic potentials exhibited by the all-male cyp17a1-deficient zebrafish with impaired estrogen biosynthesis, we demonstrated that they can be used as an excellent in vivo model for the evaluation of EEs. Environ Toxicol Chem 2024;43:1062-1074. © 2024 SETAC.
Asunto(s)
Estrógenos , Esteroide 17-alfa-Hidroxilasa , Vitelogeninas , Pez Cebra , Animales , Masculino , Esteroide 17-alfa-Hidroxilasa/genética , Vitelogeninas/genética , Estrógenos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Compuestos de Bencidrilo/toxicidad , Estradiol , Fenoles/toxicidad , Femenino , Fluorocarburos/toxicidad , Testículo/efectos de los fármacos , Testículo/metabolismoRESUMEN
In temperate climates, honey bees show strong phenotypic plasticity associated with seasonal changes. In summer, worker bees typically only survive for about a month and can be further classified as young nurse bees (which feed the developing brood) and older forager bees. In winter, brood production and foraging halt and the worker bees live for several months. These differences in task and longevity are reflected in their physiology, with summer nurses and long-lived winter bees typically having large fat bodies, high expression levels of vitellogenin (a longevity-, nutrition- and immune-related gene), and large provisioning glands in their head. The environmental factors (both within the colony and within the surrounding environment) that trigger this transition to long-lived winter bees are poorly understood. One theory is that winter bees are an extended nurse bee state, brought on by a reduction in nursing duties in autumn (i.e. lower brood area). We examined that theory here by assessing nurse bee physiology in both the summer and autumn, in colonies with varying levels of brood. We found that season is a better predictor of nurse bee physiology than brood area. This suggests that seasonal factors beyond brood area, such as pollen availability and colony demography, may be necessary for inducing the winter bee phenotype. This finding furthers our understanding of winter bee biology, which could have important implications for colony management for winter, a critical period for colony survival.
Asunto(s)
Medio Social , Vitelogeninas , Abejas , Animales , Humanos , Estaciones del AñoRESUMEN
In Dermanyssus gallinae, a hematophagous mite, the initiation of vitellogenesis induced by blood feeding is essential for its reproduction. However, the precise gene structures and physiological functions of Vg in D. gallinae and its upstream gene, Target of Rapamycin (TOR), have not been fully understood. This study revealed the presence of four homologous genes within D. gallinae, named Dg-Vg1, Dg-Vg1-like, Dg-Vg2, and Dg-Vg2-like, especially, Dg-Vg2-like was firstly identified in the mites. The expression levels of all these Vg genes were significantly higher in adult females than other stages. Following blood feeding, the expression levels of these genes increased significantly, followed by a subsequent decrease, aligning with egg production. Silencing Dg-Vgs by RNA interference (RNAi) led to decreased fecundity and egg hatching rates, as well as abnormal embryonic development, suggesting a vital role for Dg-Vgs in both egg formation and embryonic development. Furthermore, the knockdown of Dg-TOR significantly reduced the expression of Dg-Vgs and negatively impacted the reproductive capabilities of PRMs, indicating that TOR influences PRM reproduction by regulating the expression of Dg-Vgs. In summary, these findings demonstrated the crucial roles of Dg-Vgs and Dg-TOR in PRM reproduction, highlighting their potential as targets for pest control.