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General and Comparative Endocrinology Sep 2020The African bonytongue (Heterotis niloticus) is an excellent candidate for fish farming because it has outstanding biological characteristics and zootechnical...
Identification and structural characterization of the factors involved in vitellogenesis and its regulation in the African Osteoglossiforme of aquacultural interest Heterotis niloticus (Cuvier, 1829).
The African bonytongue (Heterotis niloticus) is an excellent candidate for fish farming because it has outstanding biological characteristics and zootechnical performances. However, the absence of sexual dimorphism does not favor its reproduction in captivity or the understanding of its reproductive behavior. Moreover, no molecular data related to its reproduction is yet available. This study therefore focuses on the structural identification of the different molecular actors of vitellogenesis expressed in the pituitary gland, the liver and the ovary of H. niloticus. A transcriptomic approach based on de novo RNA sequencing of the pituitary gland, ovary and liver of females in vitellogenesis led to the creation of three transcriptomes. In silico analysis of these transcriptomes identified the sequences of pituitary hormones such as prolactin (PRL), luteinizing hormone (LH) and follicle-stimulating hormone (FSH) and their ovarian receptors (PRLR, FSHR, LHR). In the liver and ovary, estrogen receptors (ER) beta and gamma, liver vitellogenins (VtgB and VtgC) and their ovarian receptors (VLDLR) were identified. Finally, the partial transcript of an ovarian Vtg weakly expressed compared to hepatic Vtg was identified based on structural criteria. Moreover, a proteomic approach carried out from mucus revealed the presence of one Vtg exclusively in females in vitellogenesis. In this teleost fish that does not exhibit sexual dimorphism, mucus Vtg could be used as a sexing biomarker based on a non-invasive technique compatible with the implementation of experimental protocols in vivo.
Topics: Amino Acid Sequence; Animals; Aquaculture; Base Sequence; Computer Simulation; Female; Fishes; Liver; Mucus; Ovary; Prolactin; Protein Structure, Secondary; Receptors, Cell Surface; Vitellogenesis; Vitellogenins
PubMed: 32535172
DOI: 10.1016/j.ygcen.2020.113532 -
Theriogenology Mar 2022Inducing maturation of the ovaries to enable the production of good-quality eggs is critical for the successful artificial breeding of Anguilla japonica. During the...
Inducing maturation of the ovaries to enable the production of good-quality eggs is critical for the successful artificial breeding of Anguilla japonica. During the spawning season, however, the ovaries of A. japonica have been found to develop into asynchronous clutches, impeding the success of artificial breeding on a commercial scale. The dynamic molecular regulation of follicular development in the same individual was assessed by transcriptome analysis of the five stages of follicles, the pre-vitellogenic, early vitellogenic, midvitellogenic, late vitellogenic, and migratory nucleus stages in artificial maturing A. japonica. Comparisons across these developmental stages identified a total of 19,298 differentially expressed transcripts (DETs). Short time-series expression miner analysis across these DETs revealed four significant expression profiles. Gene Ontology function and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses found that some of the significantly enriched biological processes and metabolic pathways included those related to steroid hormone biosynthesis (cyp11a1, cyp17a1, cyp17a2, hsd17b1, and hsd17b12), cargo receptor activity (vtgr and vldlr), meiosis and ovulation (pgrs and mPRγ), hydration (cts and aqp1), and egg coat formation (zp). These genes and pathways were associated with serum 17β-estradiol concentrations and morphological changes. The levels of hsd17b12 and mPRγ mRNAs were much higher during the migratory nucleus stage, suggesting their respective involvement in the biosynthesis and functional pathway of the maturation-inducing steroid 17α,20β-dihydroxy-4-pregnen-3-one. The gene subtypes aqp1b and ctsd may regulate water influx into oocytes and yolk protein proteolysis, respectively. To our knowledge, the present study is the first to describe combined transcriptome profiling of asynchronously developing follicles in the same individual. The findings suggest that steroid hormone synthesis and nutrient absorption in follicular somatic cells play important roles during follicular development and maturation, despite the same external physiological surroundings.
Topics: Anguilla; Animals; Female; Gene Expression Profiling; Oocytes; Ovarian Follicle; Ovary; Transcriptome; Vitellogenesis
PubMed: 34990963
DOI: 10.1016/j.theriogenology.2021.12.031 -
Frontiers in Physiology 2023Largemouth bass (LMB) production exceeded 0.7 million tons in 2021 and has become one of the most important freshwater aquaculture species in China. The stable and fixed...
Largemouth bass (LMB) production exceeded 0.7 million tons in 2021 and has become one of the most important freshwater aquaculture species in China. The stable and fixed culture cycle led to regular and drastic price fluctuation during the past decade. Strong price fluctuation provides opportunities and challenges for the LMB industry, and out-of-season spawning (OSS) and culture will provide technical support for the opportunities. To induce OSS at a low cost, we established a controllable recirculating system that allows precise thermo-photoperiod manipulation. In the system, four experimental groups were assigned, 18NP (18°C overwintering water temperature, natural photoperiod), 18CP (18°C overwintering water temperature, controlled photoperiod), 16CP (16°C overwintering water temperature, controlled photoperiod), and NTNP (natural water temperature and natural photoperiod), to determine the effects of chilling temperature and photoperiod on spawning performance. OSS was observed in all the experimental groups without significant differences, except NTNP. The manipulated broodstock can re-spawn 3 months later in the next spring in advance. Further analysis of the volume percentage of different stages of oocytes provides a base for excellent regression between the volume percentage of the primary growth stage, cortical alveoli stage, vitellogenesis/maturation stage, and gonadal development/maturation. The results suggest that the volume percentage of oocytes is a better indicator of gonadal development and maturation than the gonadosomatic index. We also found that LMB prefers palm fiber as a spawning nest over gravel. The findings of this work provide important technique guidance for practical OSS of the LMB aquaculture industry and standardization of ovary development and maturation in fish with asynchronous developmental oocytes.
PubMed: 37168230
DOI: 10.3389/fphys.2023.1175075 -
Biology of Reproduction Aug 2023Insulin-like growth factor 1 (Igf1) is known to promote ovarian maturation by interacting with other hormones. However, the limited research on the role of Igf1 in the...
Insulin-like growth factor 1 (Igf1) is known to promote ovarian maturation by interacting with other hormones. However, the limited research on the role of Igf1 in the energy metabolism supply of gonads has hindered further exploration. To explore the role of Igf1 in gonadal development of silver pomfret, we analyzed the expression levels and the localization of igf1 mRNA and protein during testicular and ovarian development of silver pomfret. The results of the study showed upregulation of Igf1 in the critical period of vitellogenesis and sperm meiosis, which was found to be mainly expressed in the somatic cells of the gonads. Upon adding E2 and Igf1 to cultured gonadal tissues, the expression of energy-related genes was significantly increased, along with the E2-enhanced effect of Igf1 in the testis. Importantly, stimulation of both ovaries and testes with E2 and Igf1 led to a remarkable increase in the expression of vitellogenesis and meiosis-related genes. Therefore, we conclude that Igf1 promotes vitellogenesis and sperm meiosis by regulating gonadal energy production. Moreover, the expression of Igf1 in gonads is significantly regulated by E2. These findings provide new insights for the research of Igf1 in fish breeding, thus allowing the regulation of energy metabolism between growth and reproduction for successful reproductive outcomes.
Topics: Animals; Female; Male; Insulin-Like Growth Factor I; Semen; Gonads; Ovary; Perciformes; Energy Metabolism
PubMed: 37228017
DOI: 10.1093/biolre/ioad058 -
PeerJ 2023Insulin-like growth factor (IGF) and other insulin-like peptides (ilps) are important hormones regulating growth and development in animals. Whereas most animals have a...
BACKGROUND
Insulin-like growth factor (IGF) and other insulin-like peptides (ilps) are important hormones regulating growth and development in animals. Whereas most animals have a single female and male adult phenotype, in some insect species the same genome may lead to different final forms. Perhaps the best known example is the honeybee where females can either develop into queens or workers. More extreme forms of such polyphenism occur in termites, where queens, kings, workers and soldiers coexist. Both juvenile hormone and insulin-like peptides are known to regulate growth and reproduction as well as polyphenism. In termites the role of juvenile hormone in reproduction and the induction of the soldier caste is well known, but the role of IGF and other ilps in these processes remains largely unknown. Here the various termite ilps are identified and hypotheses regarding their functions suggested.
METHODS
Genome assemblies and transcriptome short read archives (SRAs) were used to identify insulin-like peptides and neuropeptides in termites and to determine their expression in different species, tissues and castes.
RESULTS AND DISCUSSION
Termites have seven different ilps, gonadulin, IGF and an ortholog of insulin-like peptide 7 (dilp7), which are commonly present in insects, and four smaller peptides, that have collectively been called short IGF-related peptides (sirps) and individually atirpin, birpin, cirpin and brovirpin. Gonadulin is lost from the higher termites which have however amplified the brovirpin gene, of which they often have two or three paralogs. Based on differential expression of these genes it seems likely that IGF is a growth hormone and atirpin an autocrine tissue factor that is released when a tissue faces metabolic stress. Birpin seems to be responsible for growth and in the absence of juvenile hormone this may lead to reproductive adults or, when juvenile hormone is present, to soldiers. Brovirpin is expressed both by the brain and the ovary and likely stimulates vitellogenesis, while the function of cirpin is less clear.
Topics: Female; Male; Animals; Bees; Isoptera; Insulin; Somatomedins; Insecta; Neuropeptides; Reproduction; Insulin, Regular, Human; Juvenile Hormones; Drosophila
PubMed: 37128206
DOI: 10.7717/peerj.15259 -
Comparative Biochemistry and... Sep 2020When successive stages of an organism's life-history overlap, conflicts and trade-offs can emerge due to competition among physiological pathways. For example, long...
When successive stages of an organism's life-history overlap, conflicts and trade-offs can emerge due to competition among physiological pathways. For example, long periods of sustained locomotion in migrating birds are supported by the androgenic up-regulation of aerobic factors, such as new red blood cell production and hematocrit. However, towards the end of migration, many female birds begin up-regulating 17ß-estradiol (E) to support vitellogenesis and egg production, but E secretion is known to have suppressive effects on red blood cell production (anti-erythropoiesis). We explored potential trade-offs between factors related to aerobic performance (hematocrit, reticulocyte index) and the expression of factors related to E-mediated vitellogenesis (i.e. yolk precursor production) in female macaroni penguins (Eudyptes chrysolophus), a species in which the physiologies controlling egg production and migratory activity run simultaneously (e.g. females experience a migratory conflict). We collected blood samples from penguins immediately upon their return to the colony, prior to egg laying. Hematocrit was elevated when the penguins returned to the colony (50.05% ± 3.40 SD), which is similar to pre-laying values observed in other migratory bird species. Furthermore, mean reticulocyte levels were elevated (34.87% ± 2.34), which is the highest level yet recorded in birds. Similarly, both plasma vitellogenin and yolk-targeted very low density lipoprotein levels were upregulated (2.30 ± 0.06 μg Zn ml, and 9.70 ± 0.19 mmol l, respectively), indicating that penguins were reproductively active and producing eggs during migration and upon arrival on land. As predicted, a negative relationship between hematocrit and plasma vitellogenin was found, but we found no evidence to suggest that birds were experiencing reproductive anemia. Alternatively, we attribute the negative relationship to a hemodilution effect of yolk precursor secretion into circulation. It appears that female macaroni penguins are able to preserve hematocrit levels and new red blood cell production when migratory activity overlaps with reproductive processes.
Topics: Androgens; Animal Migration; Animals; Estradiol; Female; Hematocrit; Oxygen Consumption; Reproduction; Spheniscidae; Vitellogenins
PubMed: 32535235
DOI: 10.1016/j.cbpa.2020.110742 -
Frontiers in Endocrinology 2021The role G-protein coupled estrogen receptor (GPER) plays in vertebrate reproduction remains controversial. To investigate GPER's reproductive role, we generated a gper...
The role G-protein coupled estrogen receptor (GPER) plays in vertebrate reproduction remains controversial. To investigate GPER's reproductive role, we generated a gper zebrafish mutant line ( ) using TALENs. Gper mutant females exhibited reduced fertility with a 40.85% decrease in embryo production which was associated with a significant decrease in the number of Stage V (730-750 μm) ovulated oocytes. Correspondingly, the number of early vitellogenic follicles (Stage III, 400-450 µm) in ovaries was greater than that in wildtypes (), suggesting that subsequent follicle development was retarded in the fish. Moreover, plasma vitellogenin levels were decreased in females, and epidermal growth factor receptor (Egfr) expression was lower in Stage III vitellogenic oocytes than in counterparts. However, hepatic nuclear estrogen receptor levels were not altered, and estrogen levels were elevated in ovarian follicles. These results suggest that Gper is involved in the control of ovarian follicle development regulation of vitellogenesis and Egfr expression in zebrafish.
Topics: Animals; Cell Membrane; ErbB Receptors; Estrogens; Female; Fertility; Fishes; Metabolomics; Mutation; Oocytes; Ovarian Follicle; Ovulation; Receptors, Estrogen; Receptors, G-Protein-Coupled; Vitellogenesis; Vitellogenins; Zebrafish; Zebrafish Proteins
PubMed: 33790865
DOI: 10.3389/fendo.2021.637691 -
General and Comparative Endocrinology Jan 2023Eyestalk-derived neuropeptides, primarily the crustacean hyperglycemic hormone (CHH) neuropeptide family, regulate vitellogenesis in decapod crustaceans. The red...
Eyestalk-derived neuropeptides, primarily the crustacean hyperglycemic hormone (CHH) neuropeptide family, regulate vitellogenesis in decapod crustaceans. The red deep-sea crab, Chaceon quinquedens, a cold-water species inhabiting depths between 200 and 1800 m, has supported a small fishery, mainly harvesting adult males in the eastern US for over 40 years. This study aimed to understand the role of eyestalk-neuropeptides in vitellogenesis in C. quinquedens with an extended intermolt stage. Chromatography shows two CHH and one MIH peak in the sinus gland, with a CHH2 peak area four times larger than CHH1. The cDNA sequence of MIH and CHH of C. quinquedens is isolated from the eyestalk ganglia, and the qPCR assay shows MIH is significantly higher only at ovarian stages 3 than 4 and 5. However, MIH transcript and its neuropeptides do differ between stages 1 and 3. While CHH transcripts remain constant, its neuropeptide levels are higher at stages 3 than 1. Additionally, transcriptomic analysis of the de novo eyestalk ganglia assembly at ovarian stages 1 and 3 found 28 eyestalk neuropeptides. A GIH/VIH or GSH/VSH belonging to the CHH family is absent in the transcriptome. Transcripts per million (TPM) values of ten neuropeptides increase by 1.3 to 2.0-fold at stage 3 compared to stage 1: twofold for Bursicon α, followed by CHH, AKH/corazonin-like, Pyrokinin, CCAP, Glycoprotein B, PDH1, and IDLSRF-like peptide, and 1.3-fold of allatostatin A and short NP-F. WXXXRamide, the only downregulated neuropeptide, decreases TPM by ∼ 2-fold at stage 3, compared to stage 1. Interestingly, neuroparsin with the highest TPM values remains the same in stages 1 and 3. The mandibular organ-inhibiting hormone is not found in de novo assembly. We report that CHH, MIH, and eight other neuropeptides may play a role in vitellogenesis in this species.
Topics: Animals; Male; Female; Brachyura; Invertebrate Hormones; Arthropod Proteins; Neuropeptides; Ganglia; DNA, Complementary; Transcriptome
PubMed: 36152768
DOI: 10.1016/j.ygcen.2022.114128 -
Ecology and Evolution Feb 2021A frequent response of organisms to climate change is altering the timing of reproduction, and advancement of reproductive timing has been a common reaction to warming...
A frequent response of organisms to climate change is altering the timing of reproduction, and advancement of reproductive timing has been a common reaction to warming temperatures in temperate regions. We tested whether this pattern applied to two common North American turtle species over the past three decades in Nebraska, USA. The timing of nesting (either first date or average date) of the Common Snapping Turtle () was negatively correlated with mean December maximum temperatures of the preceding year and mean May minimum and maximum temperatures in the nesting year and positively correlated with precipitation in July of the previous year. Increased temperatures during the late winter and spring likely permit earlier emergence from hibernation, increased metabolic rates and feeding opportunities, and accelerated vitellogenesis, ovulation, and egg shelling, all of which could drive earlier nesting. However, for the Painted Turtle (), the timing of nesting was positively correlated with mean minimum temperatures in September, October, December of the previous year, February of the nesting year, and April precipitation. These results suggest warmer fall, and winter temperature may impose an increased metabolic cost to painted turtles that impedes fall vitellogenesis, and April rains may slow the completion of vitellogenesis through decreased basking opportunities. For both species, nest deposition was highly correlated with body size, and larger females nested earlier in the season. Although average annual ambient temperatures have increased over the last four decades of our overall fieldwork at our study site, spring temperatures have not yet increased, and hence, nesting phenology has not advanced at our site for . While exhibited a weak trend toward later nesting, this response was likely due to increased recruitment of smaller females into the population due to nest protection and predator control () in the early 2000s. Should climate change result in an increase in spring temperatures, nesting phenology would presumably respond accordingly, conditional on body size variation within these populations.
PubMed: 33598126
DOI: 10.1002/ece3.7105 -
Insect Science Feb 2023Oocyte maturation is critical for insect reproduction. Vitellogenesis, the timely production and uptake of vitellogenin (Vg), is crucial for female fecundity. Vg is...
Oocyte maturation is critical for insect reproduction. Vitellogenesis, the timely production and uptake of vitellogenin (Vg), is crucial for female fecundity. Vg is synthesized in fat body and absorbed by the oocytes through endocytosis during insect oogenesis. In the silkworm, Bombyx mori, we discovered that a nucleus-enriched long-noncoding RNA (lncRNA) lncR26319 regulates Endophilin A (EndoA) - a member of the endophilin family of endocytic proteins - through competitive binding to miR-2834. The lncR26319-miR-2834-EndoA axis was required for Vg endocytosis in the silkworm; loss of EndoA or overexpression of miR-2834 significantly reduced egg numbers in virgin moths. In addition, accumulation of miR-2834 resulted in pupal and adult deformation and reduced fecundity in females. The expression of Vg, 30-kDa (30K) protein, and egg-specific protein (Esp) decreased after knockdown of EndoA or overexpression of miR-2834, while knockdown of miR-2834 had an opposite effect on the expression of Vg, 30K protein gene, and Esp. These results suggest that the lncR26319-miR-2834-EndoA axis contributes to the endocytic activity in the Vg uptake and leads to the normal progression of oogenesis in the silkworm. Thus, miR-2834 and EndoA are crucial for female reproduction and could be potential targets for new pest management strategies in lepidopterans.
Topics: Female; Animals; Bombyx; Oogenesis; Vitellogenins; Oocytes; MicroRNAs; Insect Proteins
PubMed: 35612298
DOI: 10.1111/1744-7917.13082