Mature Eggs Research Articles

MiRNAs targeted transcription factors HaGATAa/b to mediate the post-mating switch in Helicoverpa armigera female reproductive behavior.

The process of mating induces significant shifts in female reproductive behavior across various species, with the postmating behavioral switch playing a crucial role in insect reproduction. Previous studies have demonstrated the regulatory role of GATA transcription factors in vitellogenin transcription and egg formation in insects, while miRNAs have been implicated in modulating GATA expression and insect reproductive processes. Nevertheless, the precise regulatory mechanism underlying the interaction between miRNAs and GATA transcription factors in the postmating behavioral switch remains largely unexplored. In this study, we identified two key GATA transcription factors, HaGATAa and HaGATAb, as central players in orchestrating the postmating behavior of H. armigera using transcriptomics and RNAi technologies. HaGATAa was found to act upstream of HaGATAb, regulating its expression. Furthermore, we observed a postmating increase in miR-282 levels in females, targeting HaGATAa to regulate egg-laying capacity. Conversely, the decreased expression of miR-2 following mating functioned as a negative feedback regulator, influencing the expression of HaGATAb and thus impacting the postmating behavior of female individuals. Our results revealed a signal-mediated feedback regulatory mechanism that sustains female postmating behavior in H. armigera. These findings not only establish a strong basis for understanding the postmating behavior mechanisms in female moths, but also offer valuable insights for identifying potential targets for pest control strategies. © 2024 Society of Chemical Industry.

Variability in spruce beetle (Coleoptera: Curculionidae, Scolytinae) adult diapause and evidence for oocyte development prior to winter in a Colorado population.

Diapause regulates seasonal insect life cycles and may be highly variable within and among populations due to genetic and environmental variability. Both types of variation may influence how populations respond plastically or evolutionarily to changing climates. We assessed diapause variability in spruce beetle Dendroctonus rufipennis Kirby (Coleoptera: Curculionidae, Scolytinae), a major forest pest whose life cycle timing is regulated by both prepupal and adult diapauses. Using mating studies and ovary dissections, we tested for variability in adult diapause within and between collection sites in Colorado and Wyoming, USA. Ovary morphology suggested that most females from both sites enter diapause prior to egg formation (oogenesis) when reared at warm temperatures. Though previous studies suggested that adult diapause is obligate, we found that a small proportion of females from both populations terminated diapause without winter chilling in the lab. Moreover, we found that most female beetles sampled at the Colorado field site had mature ovaries relatively early in the fall, suggesting that transient exposure to low temperatures may potentiate pre-winter reproductive development. Adult diapause may act primarily as a block to prevent offspring production late in the season but not necessarily as an overwintering phenotype. Overall, our data do not suggest imminent life cycle shifts mediated by adult diapause, but if the observed variability is heritable, diapause regulation may evolve in response to changing environmental conditions.

Single-cell transcriptome sequencing reveals that Wolbachia induces gene expression changes in Drosophila ovary cells to favor its own maternal transmission.

Wolbachia is an obligate endosymbiont that is maternally inherited and widely distributed in arthropods and nematodes. It remains in the mature eggs of female hosts over generations through multiple strategies and manipulates the reproduction system of the host to enhance its spreading efficiency. However, the transmission of Wolbachia within the host's ovaries and its effects on ovarian cells during oogenesis, have not been extensively studied. We used single-cell RNA sequencing to comparatively analyze cell-typing and gene expression in Drosophila ovaries infected and uninfected with Wolbachia. Our findings indicate that Wolbachia significantly affects the transcription of host genes involved in the extracellular matrix, cytoskeleton organization, and cytomembrane mobility in multiple cell types, which may make host ovarian cells more conducive for the transmission of Wolbachia from extracellular to intracellular. Moreover, the genes nos and orb, which are related to the synthesis of ribonucleoprotein complexes, are specifically upregulated in early germline cells of ovaries infected with Wolbachia, revealing that Wolbachia can increase the possibility of its localization to the host oocytes by enhancing the binding with host ribonucleoprotein-complex processing bodies (P-bodies). All these findings provide novel insights into the maternal transmission of Wolbachia between host ovarian cells.IMPORTANCEWolbachia, an obligate endosymbiont in arthropods, can manipulate the reproduction system of the host to enhance its maternal transmission and reside in the host's eggs for generations. Herein, we performed single-cell RNA sequencing of ovaries from Drosophila melanogaster and observed the effects of Wolbachia (strain wMel) infection on different cell types to discuss the potential mechanism associated with the transmission and retention of Wolbachia within the ovaries of female hosts. It was found that the transcriptions of multiple genes in the ovary samples infected with Wolbachia are significantly altered, which possibly favors the maternal transmission of Wolbachia. Meanwhile, we also discovered that Wolbachia may flexibly regulate the expression level of specific host genes according to their needs rather than rigidly changing the expression level in one direction to achieve a more suitable living environment in the host's ovarian cells. Our findings contribute to a further understanding of the maternal transmission and possible universal effects of Wolbachia within the host.

Effects of High-Temperature Stress on Biological Characteristics of Coccophagus japonicus Compere.

The parasitoid, Coccophagus japonicus Compere (Hymenoptera: Aphelinidae) is a dominant natural enemy of Parasaissetia nigra Nietner (Hemiptera: Coccidae), an important pest of rubber trees. Much of Chinese rubber is cultivated in hotter regions such as Yunnan and Hainan, exposing applied parasitoids to non-optimal temperatures. Therefore, C. japonicus must adapt to avoid temperature-related impacts on survival and population expansion. In this study, we monitored the survival rate, developmental duration, parasitism rate, and fecundity of C. japonicus during short-term exposures to 36 °C, 38 °C, and 40 °C for 2, 4, and 6 h, as well as continuous exposures to 32 °C and 34 °C for 3 days. The results show that short-term exposure to high-temperature stress leads to decreased survival rate of C. japonicus larvae and pupae, with survival rates declining as temperature and duration increase. High-temperature stress also delayed insect development, reduced mature egg production, shortened the body length of newly emerged females, and decreased female lifespans. Moreover, continuous high-temperature stress was found to significantly impact the development and reproduction of C. japonicus. Compared with the CK (27 °C), 3 d of continuous exposure to 34 °C prolonged developmental duration, shortened the body length and lifespan of newly emerged females, reduced survival rate and single female fecundity, and significantly decreased offspring numbers and parasitism rates. Temperatures of 36 °C, 38 °C, and 40 °C decreased the mortality time of adult females to 28.78, 16.04, and 7.91 h, respectively. Adverse temperatures also affected the insects' functional response, with 8 h of stress at 36 °C, 38 °C, and 40 °C causing the control efficiency of C. japonicus on P. nigra. This level of stress in the parasitoids was found to reduce the immediate attack rate and search effect, prolong processing time, and attenuate interference between small prey. Parasitoid efficiency was lowest following exposure to 40 °C. In this study, we determined the range of high temperatures that C. japonicus populations can tolerate under short- or long-term stress, providing guidance for future field applications.

Assessing potential for biological control of Japanese giant silkworm Caligula japonica using Anastatus gansuensis, a thelytokous parasitoid firstly reported in Eupelmidae.

Caligula japonica, commonly known as Japanese giant silkworm (JGS), is a serious defoliating pest of fruit and forest trees in East Asia. To develop eco-friendly and cost-effective control methods for this pest, we evaluated the potential for biological control of JGS using its egg parasitoid Anastatus gansuensis reared on the Chinese oak silkworm (COS) Antheraea pernyi. We compared the reproductive traits and population increase potential of the parasitoid on JGS and COS eggs, as well as its functional response to host egg densities and mutual interference at different parasitoid densities. Anastatus gansuensis was confirmed to be strictly synovigenic, with most eggs maturing post-emergence, and produced <1% male offspring on both host eggs. Although A. gansuensis females reared from COS eggs had longer longevity and oviposition period, and higher fecundity and net reproductive rate compared to those reared from JGS eggs, the parasitoid had a higher intrinsic rate of increase on JGS than COS eggs. The parasitoid exhibited a type II functional response to increasing host densities, with mutual interference among foraging female wasps occurred at higher parasitoid densities. Our results indicate a high potential for biological control of JGS using A. gansuensis. The parasitoid can be efficiently reared on COS eggs and used against JGS. It may be essential to provide food for emerging adult parasitoids allowing time for egg maturation prior to the rearing or augmentative release of the parasitoid. Some mutual interference at high parasitoid rearing densities likely reduces per capita parasitization efficiency of A. gansuensis. © 2024 Society of Chemical Industry.

Acute exposure to mercury drives changes in gene expression in Drosophila melanogaster.

We quantified the effect of acute exposure to a high dosage of inorganic mercury on gene expression in Drosophila melanogaster using RNA-sequencing of whole adult females. We found 119 genes with higher gene expression following treatment (including all 5 Drosophila metallothionine genes and a number of heat shock protein genes), and 31 with lower expression (several of which are involved in egg formation). Our results highlight biological processes and genetic pathways impacted by exposure to this toxic metal, and provide motivation for future studies to understand the genetic basis of response to mercury.

Temporal variability in host availability alters the outcome of competition between two parasitoid species.

Variability in the availability of resources through time is a common attribute in trophic interactions, but its effects on the fitness of different consumer species and on interspecific competition between them are not clearly understood. To investigate this, we allowed two parasitoid species, Trichopria drosophilae and Pachycrepoideus vindemiae, to exploit Drosophila host pupae under different temporal variability treatments, either on their own or simultaneously. When tested individually (in the absence of interspecific competition), both parasitoid species had lower fitness when hosts were exposed for a short duration at high density than when exposed for a long duration at low density. When both parasitoid species exploited hosts simultaneously, interspecific competition significantly decreased the number of offspring for both parasitoid species. The outcome of this interspecific competition depended on host temporal variability, with T. drosophilae or P. vindemiae dominating in short and long host exposure treatments, respectively. These results can be explained by the combination of host availability and egg load of female adult parasitoids. When abundant hosts are provided for a short period, the ample mature eggs of the proovigenic T. drosophilae enable them to exploit hosts more efficiently than P. vindemiae, which is synovigenic. However, P. vindemiae is an intrinsically superior competitor and dominates when multiparasitism occurs. Multiparasitism is more frequent when hosts are at low levels relative to the egg load of the parasitoids. Our results clearly demonstrate that resource temporal availability can alter the outcome of competition between consumers with different reproductive traits.

The signal that stimulates mammalian embryo development.

Embryo development is stimulated by calcium (Ca2+) signals that are generated in the egg cytoplasm by the fertilizing sperm. Eggs are formed via oogenesis. They go through a cell division known as meiosis, during which their diploid chromosome number is halved and new genetic combinations are created by crossing over. During formation the eggs also acquire cellular components that are necessary to produce the Ca2+ signal and also, to support development of the newly formed embryo. Ionized calcium is a universal second messenger used by cells in a plethora of biological processes and the eggs develop a "toolkit", a set of molecules needed for signaling. Meiosis stops twice and these arrests are controlled by a complex interaction of regulatory proteins. The first meiotic arrest lasts until after puberty, when a luteinizing hormone surge stimulates meiotic resumption. The cell cycle proceeds to stop again in the middle of the second meiotic division, right before ovulation. The union of the female and male gametes takes place in the oviduct. Following gamete fusion, the sperm triggers the release of Ca2+ from the egg's intracellular stores which in mammals is followed by repetitive Ca2+ spikes known as Ca2+ oscillations in the cytosol that last for several hours. Downstream sensor proteins help decoding the signal and stimulate other molecules whose actions are required for proper development including those that help to prevent the fusion of additional sperm cells to the egg and those that assist in the release from the second meiotic arrest, completion of meiosis and entering the first mitotic cell division. Here I review the major steps of egg formation, discuss the signaling toolkit that is essential to generate the Ca2+ signal and describe the steps of the signal transduction mechanism that activates the egg's developmental program and turns it into an embryo.

Salinity tolerance of the invasive blue crab Callinectes sapidus: From global to local, a new tool for implementing management strategy

The latest report from the Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) raises concerns about the global proliferation of non-native species (NIS) driven by increasing temperatures. In 2023, the invasive blue crab Callinectes sapidus experienced a significant range expansion in the French Mediterranean lagoons, now present in over 20 lagoons and numerous estuaries with different invasion gradients. It has been established that this species is eurytherm (tolerates a wide range of temperatures; 0–40 °C), rendering temperature a non-limiting factor for its proliferation. On the other hand, salinity is a critical factor to consider, as C. sapidus requires brackish water for copulation and saline water for egg maturation. In this study, we present the salinity tolerance of C. sapidus using the metabolic performance to define the tolerance of the species to a large range of salinities (13 levels from 0 to 65 psu). Results showed that C. sapidus tolerates a large range of salinities with a minimum critical threshold (CTmin) at 0 psu, an optimum at 18.5 psu, and a CTmax at 62.4 psu. Using the performance curve equation, we applied the curve to real salinity data measured each month in 2023 in 20 lagoons invaded. Using this approach, we were able to map, on a fine spatial scale, the distribution of suitable habitats for C. sapidus in the year 2023. Additionally, we have developed a tool to prioritize the lagoons based on their suitability, thereby providing a decision-making framework for management measures in each lagoon. It emerged that 50 % of lagoons were priority areas, 10 % were intermediate and 40 % required monitoring. On the basis of this approach, we can respond to European regulations to help decision-makers implement action plans and/or early detection programs for invasive species management.

Plasma Biochemistry, Intestinal Health, and Transcriptome Analysis Reveal Why Laying Hens Produce Translucent Eggs.

Producing translucent eggs has been found to reduce the quality and safety of the eggs, as well as the demand from consumers. However, the intestinal function and the molecular mechanism for the production of translucent eggs remain uncertain. A total of 120 eggs from 276-day-old Jining Bairi were divided into two groups based on eggshell translucence: the translucent egg group (group T) and the normal group (group C). Group T exhibited thicker eggshells and a lower egg yolk color. Subsequently, we divided the chickens into translucent and normal groups based on their egg quality. We then assessed the plasma biochemical index, intestinal morphology and structure, enzyme activity, and antioxidant capacity of the hens producing translucent eggs compared to those producing normal eggs. The results showed that the ratio of duodenal villus length to crypt depth, succinate dehydrogenase (SDH) activity, chymotrypsin, total ATPase (T-ATPase), alkaline phosphatase (AKP), and glutathione peroxidase (GSH-Px) activities were decreased in the hens produced translucent eggs (p < 0.05), but malondialdehyde (MDA) content was increased (p < 0.05); jejunal lipase activity, Na+K+-ATPase activity, total antioxidant capacity (T-AOC), and GSH-Px activities were decreased (p < 0.05) in group T; ileal amylase and Ca2+Mg2+-ATPase activities were also decreased (p < 0.05) in group T. In addition, we identified a total of 471 differentially expressed genes (DEGs) in duodenal tissue, with 327 up-regulated genes and 144 down-regulated genes (|log2FC| ≥ 1 and p < 0.05). Enrichment analysis showed that the up-regulated genes, such as GSTT1, GSTO2, and GSTA3, were mostly enriched in metabolism of xenobiotics by cytochrome P450, drug metabolism-cytochrome P450, and oxidative phosphorylation pathways. The results of our study indicate that plasma lipid metabolism disorder, decreased intestinal antioxidant capacity, and altered intestinal metabolism capabilities may influence the formation of translucent eggs.

Premeiotic endoreplication is the mechanism of obligate parthenogenesis in rock lizards of the genus Darevskia.

Among vertebrates, obligate parthenogenesis occurs exclusively in squamate reptiles. Premeiotic endoreplication in a small subset of developing oocytes has been documented as the mechanism of production of unreduced eggs in minutely explored obligate parthenogenetic lineages, namely in teiids and geckos. The situation in the lacertid genus Darevskia has been discussed for decades. Certain observations suggested that the ploidy level is restored during egg formation through a fusion of egg and polar body nuclei in Darevskia unisexualis and D. armeniaca. In this study, we re-evaluated the fusion hypothesis by studying diplotene chromosomes in adult females of sexual species D. raddei nairensis and obligate parthenogens D. armeniaca, D. dahli and D. unisexualis. We revealed 19 bivalents in the sexual species and 38 bivalents in the diploid obligate parthenogens, which uncovers premeiotic endoreplication as the mechanism of the production of non-reduced eggs in parthenogenetic females. The earlier contradicting reports can likely be attributed to the difficulty in identifying mispairing of chromosomes in pachytene, and the fact that in parthenogenetic reptiles relying on premeiotic endoreplication only a small subset of developing oocytes undergo genome doubling and overcome the pachytene checkpoint. This study highlights co-option of premeiotic endoreplication for escape from sexual reproduction in all independent hybrid origins of obligate parthenogenesis in vertebrates studied to date.

First Report of the Root‐Knot Nematode Meloidogyne incognita Infecting Ficus tikoua in China

ABSTRACTFicus tikoua can be used as resources for fruit and herbal medicine inspiring large‐scale planting in China. Nodular galls were found on the roots of the planted F. tikoua individuals in 2022. The mature females and egg masses of nematodes were extracted from the nodular galls, and microscopic examination suggested Meloidogyne infection. Molecular identification based on ITS, 18S rRNA sequences assigned the infecting species to Meloidogyne incognita, which was further demonstrated by the successful application of specific SCAR marker M. incognita in all samples. The pathogenicity of M. incognita was conducted on F. tikoua cutting seedlings based on Koch's postulates. This is the first report of M. incognita infection in F. tikoua in China.

Prenatal diagnosis and molecular cytogenetic analyses of a homozygous Robertsonian translocation family with novel mosaic Robertsonian fission karyotype.

Approximately one person in 1000 is a Robertsonian translocation carrier. Errors in the formation of eggs (or more rarely of sperms) may be the cause of Robertsonian translocation. Most Robertsonian translocation carriers are healthy and have a normal lifespan, but do have an increased risk of offsprings with trisomies and pregnancy loss. The fitness of Robertsonian translocation carriers is reduced, but can provide material for evolution. We have done prenatal diagnosis and molecular cytogenetic analyses on this homozygous Robertson translocation family. We report a homozygous Robertson translocation family with previously undescribed mosaic Robertsonian fission karyotype. We identified six Robertsonian translocation carriers in this family. Four were heterozygous translocation carriers of 45,XX or XY,der(14;15)(q10;q10), one was a homozygous translocation carrier of a 44,XY,der(14;15)(q10;q10),der(14;15)(q10;q10), and one was a previously undescribed Robertsonian fission carrier of 45,XN,der(14;15)(q10;q10)[42]/46,XN[58] with normal phenotype. We reported a previously undescribed mosaic Robertsonian fission karyotype. The homozygosity of Robertsonian translocation for speciation may be a potential mechanism of speciation in humans. In theory, the carriers of homologous Robertsonian translocation cannot produce normal gametes, but Robertson fission made it possible for them to produce normal gametes.

Ecofaunistic Study and Egg Morphology: Egg Laying Behavior of Hydrometra stagnorum (Linnaeus, 1753) (Gerromorpha: Heteroptera) Newly Recorded From the Karabük Province of Western Black Sea (Türkiye).

This study examines the egg-laying behavior and egg morphology of Hydrometra stagnorum (Linnaeus, 1753) (Gerromorpha: Heteroptera) to provide ecofaunistic information about the species. Newly recorded H. stagnorum samples were collected from the Karabük province of Western Black Sea region of Türkiye. Physicochemical parameters of the water were also recorded. The morphology and egg-laying behavior of H. stagnorum eggs were identified using a stereo, light and electron microscopy. Mature eggs were observed to be blackish dark brown in color. The study reveals distinctive characteristics of the egg structure and micropyle areas, which may contribute to the classification of the species at the subfamily level. Additionally, it was found that H. stagnorum inhabits high-quality waters.

Activation of the G protein-coupled sulfakinin receptor inhibits blood meal intake in the mosquito Aedes aegypti.

Little is known about the blood-feeding physiology of arbovirus vector Aedes aegypti although this type of mosquito is known to transmit infectious diseases dengue, Zika, yellow fever, and chikungunya. Blood feeding in the female A. aegypti mosquito is essential for egg maturation and for transmission of disease agents between human subjects. Here, we identify the A. aegypti sulfakinin receptor gene SKR from the A. aegypti genome and show that SKR is expressed at different developmental stages and in varied anatomical localizations in the adult mosquito (at three days after eclosion), with particularly high expression in the CNS. Knockingdown sulfakinin and sulfakinin receptor gene expression in the female A. aegypti results in increased blood meal intake, but microinjection in the thorax of the sulfakinin peptide 1 and 2 both inhibits dose dependently blood meal intake (and delays the time course of blood intake), which is reversible with receptor antagonist. Sulfakinin receptor expressed ectopically in mammalian cells CHO-K1 responds to sulfakinin stimulation with persistent calcium spikes, blockable with receptor antagonist. These data together suggest that activation of the Gq protein-coupled (i.e., calcium-mobilizing) sulfakinin receptor inhibits blood meal intake in female A. aegypti mosquitoes and could serve as a strategic node for the future control of A. aegypti mosquito reproduction/population and disease transmission.

Bioecological Characterization of Nematode Distribution Among Livestock in the North-Eastern Territories of the Lesser Caucasus of Azerbaijan Republic

Helminthological studies of sheep and goats were conducted in the northeastern territories of the Lesser Caucasus of the Republic of Azerbaijan in 2013-2022. The northeastern areas of the Lesser Caucasus include Ganja and Goygeli, Dashkesan, Geranboy, Naftalan, Samukh, Shamkir, Tovuz, Agstafa, Gazakh and Kadabek districts, as well as the areas around the Kura and Jeyranchel rivers, which are wintering places of livestock farms. This process plays a special role in the formation of helminth fauna of animals, as small horned livestock farms in these areas lead a nomadic and sedentary lifestyle. As a result of helminthological research 52 species of helminths, including 43 species of nematodes were identified. Of these, 7 species are indicated for the study region for the first time. All detected nematode species were registered in sheep, while only 26 species were found in goats, which are common to the sheep helminth fauna. These helminth species can be considered as permanent elements of the helminthofaunistic complex of livestock production in the studied region. It was found that young sheep and goats are relatively heavily infested with helminths. Infestation is higher in late spring — early summer and early fall. For this purpose, 957 sheep and 619 goats were examined for nematode pathogens in different landscape-ecological zones of the region by the method of complete helminthological autopsy according to K. I. Skryabin. Some species of helminths are absent in the studied animals before driving them to summer pastures but are observed in them after their return to wintering. Animals become infected by ingesting larvae or mature helminth eggs on summer pastures. -

Shaping Drosophila eggs: unveiling the roles of Arpc1 and cpb in morphogenesis.

The Drosophila egg chamber (EC) starts as a spherical tissue at the beginning. With maturation, the outer follicle cells of EC collectively migrate in a direction perpendicular to the anterior-posterior axis, to shape EC from spherical to ellipsoidal. Filamentous actin (F-actin) plays a significant role in shaping individual migratory cells to the overall EC shape, like in every cell migration. The primary focus of this article is to unveil the function of different Actin Binding Proteins (ABPs) in regulating mature Drosophila egg shape. We have screened 66 ABPs, and the genetic screening data revealed that individual knockdown of Arp2/3 complex genes and the "capping protein β" (cpb) gene have severely altered the egg phenotype. Arpc1 and cpb RNAi mediated knockdown resulted in the formation of spherical eggs which are devoid of dorsal appendages. Studies also showed the role of Arpc1 and cpb on the number of laid eggs and follicle cell morphology. Furthermore, the depletion of Arpc1 and cpb resulted in a change in F-actin quantity. Together, the data indicate that Arpc1 and cpb regulate Drosophila egg shape, F-actin management, egg-laying characteristics and dorsal appendages formation.

O-012 Three Injections Protocol for IVF; a proof of concept study into elaborating the outmost patient friendly protocol in IVF

Abstract Study question To examine if 3 injections in follicular phase, with long-acting FSH, long-acting antagonist and HCG/Agonist triggering can result in efficient egg retrieval and blastocyst formation. Summary answer In this proof-of-concept study, all patients retrieved mature oocytes and ended having adequate blastocysts by receiving only 3 injections in the follicular phase. What is known already The old-fashioned way with multiple injections (majority minimum 15 injections) is still the golden IVF standard. Twenty years ago, a long-acting FSH gonadotropin brought into market (corifollitropin alpha) which represented a huge step in simplifying the follicular phase Recently, a new long-acting GnRH-antagonist emerged (degarelix) which can downregulate the hypophysis for 30 days. We have published that titrating this long-acting antagonist to 0,1mg single dose we can downregulate hypophysis without LH surge. Study design, size, duration A prospective proof of concept study included in total 15 patients 30-39 years old who followed IVF treatment with homologous oocytes during 2020-2022 in Assisting Nature IVF Clinic, Thessaloniki, Greece. In this study, we test if by delaying one day the long-FSH and also delaying the long-antagonist, still patients can produce mature eggs without needed extra FSH doses. Institutional review board approved the protocol. Participants/materials, setting, methods Patients were enrolled if AMH was 1,5-3,0 ng/ml and antagonist protocol applied. 150IU fixed corifollitropin-a (Elonva) for ovarian stimulation administered either on evening cycle Day-3 or morning day-4. Fixed 0,1 mg of long-acting GnRH-antagonist (Degarelix) administered on cycle Day 8. Fixed 250mcg recombinant-hCG (Ovitrelle) or 0,3 mg of Triptorelin (Arvekap) for ovulation triggering administered as soon as 3 follicles of 18mm were present. Produced blastocysts were all cryopreserved and transferred in subsequent thawed cycles. Main results and the role of chance All 15 patients reached ovum pick-up with mature eggs retrieved (mean 13,5 oocytes). None experienced any LH surge, however, 3/15 (20%) required an extra dose of 300IU FSH (Puregon) to enhance follicular development. The majority 12/15 reached OPU without any FSH adjuvant. All 15 patients had blastocysts formed (mean 3,3) and in their subsequent thawed cycles the cumulative live birth rate was 53,3% (8/15). Patient satisfaction was excellent though closer monitoring was applied due to novelty of the protocol. Limitations, reasons for caution Limited number of patients as it is a complete novel protocol with unknown outcome. Protocol was focused in normo-ovarian-reservers to secure follicular production. Some patients might need an extra dose of gonadotropin. Long-acting antagonist still not registered for IVF use. Wider implications of the findings Current study promising results indicate that a 3-injection follicular stimulation can efficiently produce mature eggs, viable blastocysts and pregnancies. Although, few patients required an extra fourth injection of FSH, if such approach will be tested in larger studies will re-establish our way for stimulation at least for normo-reservers. Trial registration number NCT03877185

Reciprocal interactions between neuropeptide F and RYamide regulate host attraction in the mosquito Aedes aegypti

Female mosquitoes produce eggs in gonadotrophic cycles that are divided between a previtellogenic and vitellogenic phase. Previtellogenic females consume water and sugar sources like nectar while also being attracted to hosts for blood feeding. Consumption of a blood meal activates the vitellogenic phase, which produces mature eggs and suppresses host attraction. In this study, we tested the hypothesis that neuropeptide Y-like hormones differentially modulate host attraction behavior in the mosquito Aedes aegypti. A series of experiments collectively indicated that enteroendocrine cells (EECs) in the posterior midgut produce and release neuropeptide F (NPF) into the hemolymph during the previtellogenic phase which stimulates attraction to humans and biting behavior. Consumption of a blood meal, which primarily consists of protein by dry weight, down-regulated NPF in EECs until mature eggs developed, which was associated with a decline in hemolymph titer. NPF depletion depended on protein digestion but was not associated with EEC loss. Other experiments showed that neurons in the terminal ganglion extend axons to the posterior midgut and produce RYamide, which showed evidence of increased secretion into circulation after a blood meal. Injection of RYamide-1 and -2 into previtellogenic females suppressed host attraction, while coinjection of RYamides with or without short NPF-2 also inhibited the host attraction activity of NPF. Overall, our results identify NPF and RYamide as gut-associated hormones in A. aegypti that link host attraction behavior to shifts in diet during sequential gonadotrophic cycles.

Cloning and functional analysis of the juvenile hormone receptor gene CsMet in Coccinella septempunctata.

The potential role of the juvenile hormone receptor gene (methoprene-tolerant, Met) in reproduction of Coccinella septempunctata L.(Coleoptera: Coccinellidae)(Coleoptera: Coccinellidae), was investigated by cloning, analyzing expression profiles by quantitative real-time PCR, and via RNA interference (RNAi). CsMet encoded a 1518-bp open reading frames with a predicted protein product of 505 amino acids; the latter contained 2 Per-Arnt-Sim repeat profile at amino acid residues 30-83 and 102-175. CsMet was expressed in different C. septempunctata larvae developmental stages and was most highly expressed in third instar. CsMet expression in female adults gradually increased from 20 to 30 d, and expression levels at 25 and 30 d were significantly higher than levels at 1-15 d. CsMet expression in 20-d-old male adults was significantly higher than in males aged 1-15 d. CsMet expression levels in fat body tissues of male and female adults were significantly higher than expression in the head, thorax, and reproductive system. At 5 and 10 d after CsMet-dsRNA injection, CsMet expression was significantly lower than the controls by 75.05% and 58.38%, respectively. Ovary development and vitellogenesis in C. septempunctata injected with CsMet-dsRNA were significantly delayed and fewer mature eggs were produced. This study provides valuable information for the large-scale rearing of C. septempunctata.