Gonadal Development Research Articles

Growth rate, meat yield, condition index and reproduction of mussels (Mytilus galloprovincialis, Lamarck 1819) integrated to a fish farm

In the current study mussels were integrated to a fish farm located at the Aegean Sea, which is providing important production sites for the European aquaculture industry. Growth and survival, meat yield, condition index were calculated and gonad development was observed monthly over a one year period from April 2018–2019. First the impact area of sea cage farm was determined and study carried out at three sitations that were identified as impact zone, sea cage center and distant zone without impact from farm site. Temperature, salinity, chlorophyll-a and particulate matter were measured monthly. It was determined that, the mussel growth of at the impact zone was statistically significant with a final size of 61.36 ± 4.2 mm which was superior than those located in the center point and far distance zone with no influence from the cage farm. The mussels in the study area were in the resting phase during the summer months; became sexually active with the decline in water temperature and spawning occurred during the winter time from December to March.

Comparative Studies on Duplicated foxl2 Paralogs in Spotted Knifejaw Oplegnathus punctatus Show Functional Diversification.

As a member of the forkhead box L gene family, foxl2 plays a significant role in gonadal development and the regulation of reproduction. During the evolution of deuterostome, whole genome duplication (WGD)-enriched lineage diversifications and regulation mechanisms occurs. However, only limited research exists on foxl2 duplication in teleost or other vertebrate species. In this study, two foxl2 paralogs, foxl2 and foxl2l, were identified in the transcriptome of spotted knifejaw (Oplegnathus punctatus), which had varying expressions in the gonads. The foxl2 was expressed higher in the ovary, while foxl2l was expressed higher in the testis. Phylogenetic reconstruction, synteny analysis, and the molecular evolution test confirmed that foxl2 and foxl2l likely originated from the first two WGD. The expression patterns test using qRT-PCR and ISH as well as motif scan analysis revealed evidence of potentially functional divergence between the foxl2 and foxl2l paralogs in spotted knifejaw. Our results indicate that foxl2 and foxl2l may originate from the first two WGD, be active in transcription, and have undergone functional divergence. These results shed new light on the evolutionary trajectories of foxl2 and foxl2l and highlights the need for further detailed functional analysis of these two duplicated paralogs.

Dietary protein requirement of female climbing perch, Anabas testudineus (Bloch, 1792) broodstock

Nutritional components are multifarious amongst different producers, whereas they are just designed for fish farming but not suitable for improving the reproductive performance of brood fish. Climbing perch, Anabas testudineus is one of the candidate species for freshwater aquaculture in Asia. However, there is little knowledge available about the nutrient requirement of A. testudineus broodstock. Therefore, a feeding trial was conducted for 90-days to optimize the dietary protein requirement for reproductive performances of A. testudineus female broodstock. Six iso-energetic (around 400 Kcal digestible energy/100 g), iso-lipidic (8%) and hetero nitrogenous (25–50% crude protein, CP) semi-purified diets namely, 25% CP (T25), 30% CP (T30), 35% CP (T35), 40% CP (T40), 45% CP (T45) and 50% CP (T50) were prepared for feeding the fish of respective group twice daily. Three hundred and sixty (360) adults A. Testudineus (average body weight 18.67 ± 0.09 g) with female and male ratio of 1:1 were randomly distributed in six treatments in triplicate with the stocking density of 20 fish/ tank (500 L water volume) following a completely randomized design. Results indicated that the gonado-somatic index and viscero-somatic index increased significantly (p < 0.05) up to 40% CP then reduced gradually. But intraperitoneal fat content decreased with increasing dietary protein levels. T40 group showed lowest hepato-somatic index. The absolute fecundity was highest (p < 0.05) in 35% dietary protein fed group but found similar (p > 0.05) between T30 and T45 group. Estradiol was significantly lowest (p < 0.05) but highest 17α, 20β di-hydroxy progesterone level were observed in 35% CP fed group. Cortisol was found highest (p < 0.05) in T40, T45andT50groupand lowest in T35 group. Histological observations revealed that the females with higher proportion of vitellogenic oocytes were from 35% to 40% protein-fed groups. After induced spawning, significantly (p < 0.05) higher fecundity of spawning, rate of fertilization and hatching, and survival of larvae were observed in 40% CP fed group. Second-order polynomial regression analysis of fertilization rate (%) and larval survival (%) estimated 39.07–39.21% dietary protein is optimum for gonadal development, oocyte maturation and reproductive performance of female A. testudineus broodstock.

CRISPR/Cas9-mediated activation of NR5A1 steers female human embryonic stem cell-derived bipotential gonadal-like cells towards a steroidogenic cell fate

The nuclear receptor subfamily 5 group A member 1 (NR5A1), encoding steroidogenic factor 1 (SF-1), has been identified as a critical factor in gonadal development in animal studies. A previous study of ours suggested that upregulation of NR5A1 during early gonadal differentiation in male (46,XY) human pluripotent stem cells steers the cells into a more mature gonadal cell type. However, the detailed role of NR5A1 in female gonadal differentiation has yet to be determined. In this study, by combining the processes of gonadal differentiation and conditional gene activation, we show that NR5A1 induction predominantly upregulates the female gonadal marker inhibin subunit α (INHA) and steroidogenic markers steroidogenic acute regulatory protein (STAR), cytochrome P450 family 11 subfamily A member 1 (CYP11A1), cytochrome P450 family 17 subfamily A member 1 (CYP17A1), hydroxy-delta-5-steroid dehydrogenase (HSD3B2) and hydroxysteroid 17-beta dehydrogenase 1 (HSD17B1). In contrast, NR5A1 induction did not seem to affect the bipotential gonadal markers gata binding protein 4 (GATA4) and Wilms’ tumour suppressor 1 (WT1) nor the female gonadal markers r-spondin 1 (RSPO1) and wnt family member 4 (WNT4). Differentially expressed genes were highly associated with adrenal and ovarian steroidogenesis pathways. Moreover, time-series analysis revealed different dynamic changes between male and female induced samples, where continuously upregulated genes in female gonadal differentiation were mostly associated with adrenal steroidogenesis. Thus, in contrast to male gonadal differentiation, NR5A1 is necessary but not sufficient to steer human embryonic stem cell (hESC)-derived bipotential gonadal-like cells towards a more mature somatic, female cell fate. Instead, it seems to direct bipotential gonadal-like cells more towards a steroidogenic-like cell population. The information obtained in this study helps in elucidating the role of NR5A1 in gonadal differentiation of a female stem cell line.

Influence of seasonality and gonad development on the nutritional quality and safety of the razor clam Sinonovacula constricta (Lamarck 1818)

Understanding the reproductive activity or seasonal variation in comprehensive evaluations of the nutritional quality and safety of the razor clam Sinonovacula constricta (Lamarck) is important for improving product quality and economic benefits. The contents of moisture (from 80.12±0.38 to 84.98±0.40%), protein (from 53.14±0.06 to 63.12±0.69% DW), lipid (from 4.55±0.19 to 5.69±0.35% DW), glycogen (from 5.40±1.11 to 16.13±1.55% DW), and ash (from 12.03±0.33 to 19.86±0.56% DW) varied significantly at different gonadal development cycles or seasons. Glycogen, lipid, and protein variations were closely associated with gonadal development, with the lowest levels of lipid and protein in the spawning period. Moreover, S. constricta consistently had a well-balanced essential amino acid profile throughout the year, indicating that it is a source of high-quality protein. The predominant free amino acids in S. constricta were taurine, glycine, lysine, and alanine, which are important contributors to the flavor. S. constricta was defined as lean fat throughout the gonad cycle with polyunsaturated fatty acid accounting for the majority in the active and maturing stages. Microbiological quality and total volatile basic nitrogen were associated with the alteration of seasons. The optimal harvesting time of S. constricta was the inactive stage of most gonads in spring (from March to April in Taizhou, Zhejiang Province, China).

Genome-wide identification, evolution and expression of TGF-β signaling pathway members in mandarin fish (Siniperca chuatsi)

Members of the transforming growth factor β (TGF-β) signaling pathway regulate diverse cellular biological processes in embryonic and tissue development. We took mandarin fish (Siniperca chuatsi) as the research object to identify all members of the TGF-β signaling pathway, measure their expression pattern in the key period post hatching, and further explore their possible role in the process of sex regulation. Herein, we identified eighty-three TGF-β signaling pathway members and located them on chromosomes based on the genome of mandarin fish. TGF-β signaling pathway members were highly conserved since each TGF-β subfamily clustered with orthologs from other species. Transcriptome analysis, qRT–PCR and in situ hybridization demonstrated that most mandarin fish TGF-β signaling pathway members presented stage-specific and/or sex-dimorphic expression during gonadal development, and different members of the TGF-β signaling pathway participated in different stages of gonadal development. Taken together, our results provide new insight into the role of TGF-β signaling pathway members in the sex regulation of mandarin fish.

Examination of the role of a novel transcription factor in activating Foxl2 and its potential involvement in the regulation of ovarian development in scallops

The regulation of gonadal development remains largely unknown in bivalves, and the Foxl2 gene has been proposed as a key regulator of female development. However, limited information is available regarding its regulatory mechanisms. In our previous study on Chlamys farreri, a yeast one-hybrid assay was performed, and an unreported factor (designated Cf-FA1) that may act as a new transcription factor for activating Cf-Foxl2 transcription was identified. In the present study, we revealed that Cf-FA1 is a hydrophilic unstable protein possessing multiple proline-rich and serine/threonine-rich regions. Cf-FA1 exhibited a significantly biased expression in the ovary detected by semi-quantitative RT-PCR, and its cyto-localization was exhibited in ovarian cells during oogenesis through in situ hybridization and immunohistochemistry, while not in male gametes during spermatogenesis. Western blotting demonstrated that Cf-FA1 protein also exhibited a similar sexually dimorphic expression pattern and was more concentrated in the nucleus along with ovarian maturation. ChIP assays confirmed that Cf-FA1 binds to the Cf-Foxl2 promoter. Furthermore, the interference of Cf-FA1 expression in the ovary by in vivo RNAi led to an obvious Cf-Foxl2 expression decrease, ovary developmental retardation, gonadosomatic index decline, and female gametes reduction. These results suggest that Cf-FA1 acts as a transcription factor to activate Foxl2 transcription and participates in ovarian development and oogenesis regulation in bivalves, providing an important basis for sex control breeding in aquaculture.

Comparative transcriptome analysis reveals key genes and pathways related to gonad development in the sea cucumber Apostichopus japonicus

The sea cucumber Apostichopus japonicus is an economically important marine species in China, and understanding the mechanisms underlying its gonad development is crucial for successful reproduction and breeding. In this study, we performed transcriptome comparisons and analyses of A. japonicus gonadal and non-gonadal tissues to identify genes and molecular pathways associated with gonadal development. We also supplemented the annotation of the A. japonicus genome. Collectively, results revealed a total of 941 ovary-specific genes and 2499 testis-specific genes through different expression analysis and WGCNA analysis. The most enriched pathways in ovary and testis were “DNA replication” and “purine metabolism”, respectively. Additionally, we identified key candidate gene modules that control gonad development and germ cell maturation, with CDT1 and DYNC2LI1 serving as hub genes. Our findings provide important insights into the gonadal development system of A. japonicus and offer valuable references for further research on reproductive biology in this marine invertebrate species.

The roles of soybean lecithin in aquafeed: a crucial need and update.

Soybean lecithin is extensively used as the dietary supplementation of phospholipids in animal production. Soybean lecithin plays significant roles in aquafeed as growth promoter, feed enhancer, immunity modulator and antioxidant activity stimulator for aquaculture species. Besides, soybean lecithin is also reported to help aquaculture species being resilient to physical and chemical stressors. In this review, common sources, chemical structure and mode of action of lecithin, with highlight on soybean lecithin application in aquaculture over four-decadal studies published between 1983 and 2023, were evaluated and summarized. By far, soybean lecithin is best-known for its beneficial effects, availability yet cost-effective for aquafeed formulation. Findings from this review also demonstrate that although nutritional profile of long-chain polyunsaturated fatty acids and phosphatidylcholine from egg yolk and marine sources are superior to those from plant sources such as soybean, it is rather costly for sustainable application in aquafeed formulation. Moreover, commercially available products that incorporate soybean lecithin with other feed additives are promising to boost aquaculture production. Overall, effects of soybean lecithin supplementation are well-recognized on larval and juvenile of aquaculture species which having limited ability to biosynthesis phospholipids de novo, and correspondingly attribute to phospholipid, a primary component of soybean lecithin, that is essential for rapid growth during early stages development. In addition, soybean lecithin supplementation plays a distinguish role in stimulating maturation of gonadal development in the adults, especially for crustaceans.

Reproductive Characteristics and Germ Cell Status of Indian Major Carp, &lt;i&gt;Labeo rohita&lt;/i&gt; Reared in Elevated Water Temperature Regime

Rearing water temperature and fluctuations in it has a profound effect on survival and gonadal development of fish. Reproduction in fish, compared with other physiological processes, only occurs in a bounded temperature range; therefore, small changes in water temperature could significantly affect this process. Here we analysed the effects of different rearing water temperatures (28 °C, 30 °C, 32 °C, 34 °C and 36 °C) and a cytotoxic drug (busulfan) on germ cell status and maturation in Indian major carp, Labeo rohita. The effectiveness of the treatment was assessed by gonadosomatic index, histology and dye uptake of GC. Thermo-chemical treatments were given either: as elevated water temperature alone (0.69±0.09) or in combination with busulfan that showed a low GSI value (0.49±0.26) as compared to control (0.88±0.009). Gonadal morphology visibly shrunk after the thermochemical treatments. Similarly, the gonadal histology confirmed that the GC depletion took place when the rohu were reared at elevated temperature along with the application of a cytotoxic drug busulfan (40 mg/kg). According to the deteriorating reproductive responses of the fish by temperature fluctuations, it is plausible that changes may affect aquaculture production and affecting future populations of fish, so new strategies for amelioration should be anticipated.

Experiencing short heat waves early in development changes thermal responsiveness of turtle embryos to later heat waves.

Although physiological responses to the thermal environment are most frequently investigated using constant temperatures, the incorporation of thermal variability can allow for a more accurate prediction of how thermally sensitive species respond to a rapidly changing climate. In species with temperature-dependent sex determination (TSD), developmental responses to incubation temperature are mediated by several genes involved in gonadal differentiation. Kdm6b and Dmrt1 respond to cool incubation temperatures and are associated with testis development, while Foxl2 and Cyp19A1 respond to warm incubation temperatures and are associated with ovary development. Using fluctuating incubation temperatures, we designed two studies, one investigating how conflicting thermal cues affect the timing of commitment to gonadal development, and another investigating the rapid molecular responses to conflicting thermal cues in the red-eared slider turtle (Trachemys scripta). Using gene expression as a proxy of timing of commitment to gonadal fate, results from the first study show that exposure to high amounts of conflicting thermal cues during development delays commitment to gonadal fate. Results from the second study show that Kdm6b splice variants exhibit differential responses to early heat wave exposure, but rapidly (within 2 days) recover to pre-exposure levels after the heat wave. Despite changes in the expression of Kdm6b splice variants, there was no effect on Dmrt1 expression. Collectively, these findings demonstrate how short exposures to heat early in development can change how embryos respond to heat later in development.

Iso-seq and RNA-seq profiling of Fenneropenaeus penicillatus: Unravelling the signaling pathway and genes involved in the ovarian development

The impediment of inadequate shrimp gonad development has adversely affected their production in the aquaculture sector. One promising strategy to enhance the quality and timing of offspring for commercial purposes is the regulation of their reproductive activity. Nevertheless, the availability of information pertaining to ovarian development in Fenneropenaeus penicillatus remains limited. To address this knowledge gap, our study employed a multi-faceted approach, integrating cutting-edge technologies such as Iso-seq, RNA-seq, RT-qPCR, histological and morphological observations. The Iso-seq generating 81,964,598 subreads with an average length of 1600 bp. This effort yielded 926,713 CCS reads and 557,043 FLNC reads, culminating in a robust set of 16,587 non-redundant full-length transcripts. This study utilized CPC, CPAT, PLEK, and pfam, to predict the numbers of long non-coding RNAs (lncRNAs). The outcomes were as follows: 5204, 4478, 7055, and 8175 lncRNAs, respectively. Our findings unveiled the intricate molecular underpinnings of ovarian development, encompassing pivotal pathways such as oocyte meiosis, insulin signaling pathway, oxytocin signaling pathway, progesterone-mediated oocyte maturation, estrogen signaling pathway, and GnRH signaling pathway. Notably, we identified specific genes—including Vtg, VgR, Sxl4, UCH, Hsp70, PP1, CDK2, Rheb, MKK3, and CDC42—that exhibited dynamic expression patterns during ovarian development. This study has produced a comprehensive dataset of full-length transcripts that holds significant potential as a genomic reference for future research on F. penicillatus. Furthermore, these insights may substantially contribute to the advancement of artificial breeding techniques and the ongoing development of sustainable aquaculture practices for F. penicillatus.

How do maternal androgens and estrogens affect sex determination in reptiles with temperature-dependent sex?

Temperature sex determination (TSD) in reptiles has been studied to elucidate the mechanisms by which temperature is transformed into a biological signal that determines the sex of the embryo. Temperature is thought to trigger signals that alter gene expression and hormone metabolism, which will determine the development of female or male gonads. In this review, we focus on collecting and discussing important and recent information on the role of maternal steroid hormones in sex determination in oviparous reptiles such as crocodiles, turtles, and lizards that possess TSD. In particular, we focus on maternal androgens and estrogens deposited in the egg yolk and their metabolites that could also influence the sex of offspring. Finally, we suggest guidelines for future research to help clarify the link between maternal steroid hormones and offspring sex.

Transcriptome Sequencing Analysis of Sex-Related Genes in the Gonads of Mytilus unguiculatus

In the cultivation of Mytilus unguiculatus, the broodstock are shade-dried to stimulate sperm and egg production. To identify the functional genes affecting gonad development in M. unguiculatus, the transcriptome of gonads in mussels stimulated by shade-drying and those not stimulated were compared. Differential gene expression analysis revealed that there were 22 differentially expressed genes (DEGs) in the testis and 70 DEGs in the ovary among the experimental groups. KEGG enrichment analysis identified a total of 11 pathways that might be related to environmental stimuli affecting gonadal development. Nicotinic acetylcholine receptors (AChRs), the cholecystokinin A receptor (CCKAR), hypocretin (orexin) receptor 2 (HCRTR2), and gamma-aminobutyric acid type B receptor (GABBR) were highly expressed in the neuroactive ligand-receptor interaction pathway, indicating that these genes might be involved in the transduction of environmental information that stimulates gonadal development. Meanwhile, nuclear receptor co-repressor 2 (NCoR2) was highly expressed in the notch signaling pathway, indicating that NCoR2 might be involved in the regulation of gonad development. To validate the transcriptome data, we selected five DEGs in the KEGG signaling pathway, including AChRs, CCKAR, HCRTR2, GABAB, and NCoR2, for real-time quantitative PCR (RT-qPCR), which produced results consistent with the RNA-Seq data. The transcriptome analysis and gene pathway identification in this study have enhanced our comprehension of the reproductive mechanisms in M. unguiculatus.

Spawning aggregations of checkered snapper (Lutjanus decussatus) and blackspot snapper (L. fulviflamma): seasonality, lunar-phase periodicity and spatial distribution within spawning ground.

Snappers (family Lutjanidae) are important fisheries target species and some species are known to form spawning aggregations at particular spawning grounds. The present study investigated the ecological characteristics of fish aggregations of two snapper species (checkered snapper Lutjanus decussatus and blackspot snapper L. fulviflamma) that form at a particular site. Specifically, the aims were to clarify (1) seasonality and lunar-phase periodicity of fish aggregation formation, (2) fine-scale spatial distribution of fish density (spatial variations of fish density at intervals of several-tens meters) within the aggregation site, (3) size and age frequency distributions of fishes in the aggregation site, (4) gonad development, (5) to compare fish abundance between inside and outside the aggregation site, and (6) to verify that fish aggregations of the two snapper species were spawning aggregation. Underwater observations using a 600m×5m transect revealed that greater fish abundance of Lutjanus decussatus was found monthly between May and October, and clear positive peaks in the fish abundance were found only around the last-quarter moon. This lunar-related periodicity in the increase of fish abundance was confirmed by a time-series analysis (correlogram). Within the aggregation site, L. decussatus showed a relatively uniform distribution. In contrast, greater fish abundance of L. fulviflamma was found monthly between April and October, and clear positive peaks in the fish abundance were found around the last-quarter moon (April, May, June and October) or new moon (July, August and September). This lunar-related periodicity was also confirmed by correlogram. Lutjanus fulviflamma showed a relatively clumped distribution within the aggregation site. Most females of the two species in the aggregation site had hydrated eggs, indicating that the two species form aggregations for reproduction. The two species, although occurring simultaneously, are considered to form aggregations of conspecifics only. For L. decussatus, average fork length and age of males and females were 229.2 mm and 243.9 mm and 9.4 years and 8.1 years, respectively. For L. fulviflamma, average fork length and age of males and females were 233.9 mm and 246.9 mm and 6.8 years and 8.1 years, respectively. Fish abundance inside the aggregation site was 266.8-fold and 141557.1-fold greater than those outside the aggregation site for L. decussatus and L. fulviflamma, respectively. These results showed that (1) fish aggregation formation of the two snapper species was predictably repeated in particular months and lunar-phase, (2) it was predictably found at the particular site, (3) the fish abundance in the aggregation site markedly exceeded the fish abundance outside the aggregation site, and (4) the two species form aggregations for reproduction. Therefore, it is suggested that the fish aggregations for the two species can be regarded as spawning aggregations.

Etiology, histology, and long-term outcome of bilateral testicular regression: a large Belgian series

Abstract STUDY QUESTION What is the long-term outcome of individuals born with bilateral testicular regression (BTR) in relation to its underlying etiology? SUMMARY ANSWER Statural growth and pubertal development are adequate with incremental doses of testosterone replacement therapy (TRT); however, penile growth is often suboptimal, especially in those with a suspected genetic etiology (i.e. heterozygous DHX37 variants) or a micropenis at birth. WHAT IS KNOWN ALREADY BTR is a rare and poorly understood condition. Although a vascular origin has been postulated, heterozygous missense variants in DHX37 have been attributed to the phenotype as well. How these various etiologies impact the clinical phenotype, gonadal histology and outcome of BTR remains unclear. STUDY DESIGN, SIZE, DURATION For this cross-sectional study, individuals with BTR were recruited in eight Belgian pediatric endocrinology departments, between December 2019 and December 2022. A physical exam was performed cross-sectionally in all 17 end-pubertal participants and a quality of care questionnaire was completed by 11 of them. Exome-based panel testing of 241 genes involved in gonadal development and spermatogenesis was performed along with a retrospective analysis of presentation and management. A centralized histological review of gonadal rests was done for 10 participants. PARTICIPANTS/MATERIALS, SETTING, METHODS A total of 35 participants (33 with male, 1 with female, and 1 with non-binary gender identity) were recruited at a mean age of 15.0 ± 5.7 years. MAIN RESULTS AND THE ROLE OF CHANCE The median age at presentation was 1.2 years [0–14 years]. Maternal gestational complications were common (38.2%), with a notably high incidence of monozygotic twin pregnancies (8.8%). Heterozygous (likely) pathogenic missense variants in DHX37 (p.Arg334Trp and p.Arg308Gln) were found in three participants. No other (likely) pathogenic variants were found. All three participants with a DHX37 variant had a microphallus at birth (leading to female sex assignment in one), while only six of the remaining 31 participants without a DHX37 variant (19.4%) had a microphallus at birth (information regarding one participant was missing). Testosterone therapy during infancy to increase penile growth was more effective in those without versus those with a DHX37 variant. The three participants with a DHX37 variant developed a male, female, and non-binary gender identity, respectively; all other participants identified as males. TRT in incremental doses had been initiated in 25 participants (median age at start was 12.4 years). Final height was within the target height range in all end-pubertal participants; however, 5 out of 11 participants (45.5%), for whom stretched penile length (SPL) was measured, had a micropenis (mean adult SPL: 9.6 ± 2.5). Of the 11 participants who completed the questionnaire, five (45.5%) reported suboptimal understanding of the goals and effects of TRT at the time of puberty induction. Furthermore, only 6 (54.5%) and 5 (45.5%) of these 11 participants indicated that they were well informed about the risks and potential side effects of TRT, respectively. Histological analysis of two participants with DHX37 variants suggested early disruption of gonadal development due to the presence of Müllerian remnants in both and undifferentiated gonadal tissue in one. In eight other analyzed participants, no gonadal remnants were found, in line with the BTR diagnosis. LIMITATIONS, REASONS FOR CAUTION The limitations of this study include the relatively small sample size (n = 35) and the few individuals with DHX37 variants (n = 3). Furthermore, data on the SPL were often missing, due to this being undocumented or refused by participants. WIDER IMPLICATIONS OF THE FINDINGS TRT provides adequate statural growth, even when initiated in late adolescence, thus providing time for physicians to explore the patients’ gender identity if needed. However, sufficient and understandable information regarding the effects and side effects of TRT is required throughout the management of these patients. SPL remains suboptimal in many individuals and could be improved by TRT during infancy to mimic the physiological mini-puberty. An environmental origin in some participants is supported by the high incidence of gestational complications (38.2%) and by the three monozygotic twin pregnancies discordant for the BTR phenotype. Individuals with a heterozygous DHX37 variant have a more severe phenotype with severely restricted penile growth until adulthood. Histological analysis confirmed DHX37 as a gonadal development, rather than a BTR-related, gene. STUDY FUNDING/COMPETING INTEREST(S) Funding was provided by the Belgian Society for Pediatric Endocrinology and Diabetology (BESPEED) and by Ghent University Hospital under the NucleUZ Grant (E.D.B.). M.C. and E.D.B. are supported by an FWO senior clinical investigator grant (1801018N and 1802220N, respectively). The authors report no conflicts of interest. TRIAL REGISTRATION NUMBER N/A.

Minus-C odorant binding protein TcasOBP7G contributes to reproduction and defense against phytochemical in the red flour beetle, Tribolium castaneum

Insect odorant binding proteins (OBPs) paly an important role in the recognition and transmission signals. One odorant binding protein gene, TcasOBP7G, was significantly up-regulated after exposure to eucalyptol. Nevertheless, the causal role of TcasOBP7G in Tribolium castaneum is still unclear. Here, TcasOBP7G was cloned and characterized from T. castaneum, aligning with the typical characteristic of Minus-C OBPs. The analysis of gene expression profile showed that TcasOBP7G is highly expressed at late larval and adult stage, with particularly high expression levels in ovary and testis of adults, suggesting that TcasOBP7G might be associated with reproduction of T. castaneum. Furthermore, RNAi of TcasOBP7G led to a decrease in spawning, while the development of gonads was normal, suggesting that TcasOBP7G may medicate the reproduction of T. castaneum. Additionally, the mRNA level of TcasOBP7G was significantly increased after exposure to eucalyptol, and knockdown of TcasOBP7G resulted in an increased susceptibility of T. castaneum to eucalyptol, indicating that TcasOBP7G is associated with the tolerance of T. castaneum to eucalyptol. Altogether, these results indicate that TcasOBP7G is required for both reproduction and defense against phytochemical in T. castaneum. This study will provide a theoretical basis for the development of novel control strategies based on the olfaction of insects.

Examination of the effects of highly diluted bioactive compounds on gametogenesis in relation to energy budget and oocyte quality in mussel (Modiolus capax) broodstock

A critical bottleneck for bivalve hatcheries is the availability of mature broodstock with high-quality gametes to ensure the production of healthy spat. The use of highly diluted bioactive compounds (HDBC) has emerged as a novel and prophylactic strategy to improve gonad development, reproduction bioenergetics, and oocyte quality of marine bivalve broodstock. This study evaluates the effect of HDBC formulas to enhance the laboratory-controlled breeding capacity of Modiolus capax adult mussel, selected as a model organism because of its aquaculture potential as an alternative seafood resource. The experimental design included three replicates of three HDBC treatments at 31Centesimal (1 × 10−31) dynamizations using distilled water as the final excipient (TR1: SiT, CaS, HeS; TR2: PhA, FeP, ZnP; and TR3: ViP, ViA, ViT), and two control treatments: C+ hydro-alcoholic solution at 1% (Usual HDBC vehicle) and C- (distilled water) during a 30-day period. As a result, TR1 enhanced energy reserves (lipids and carbohydrates) in all tissues; TR2 promoted an increase in lipid and carbohydrate content in the gonad and their transfer into developing oocytes; TR3 significantly improved gonad development and reproductive capacity of the mussels with the highest proliferation of mature oocytes, enhancing food-nutrient assimilation and energetic reserve transfer from the somatic tissues to the ovary. Additionally, all HDBC formulas recorded a lower (P < 0.05) number of atretic oocytes compared to the untreated animals. This evidence reflects a simultaneous improvement of gametogenesis and energy budget of M. capax broodstock, ensuring sexual maturation and higher-quality oocytes when HDBC are used.

The Gonadal Maturity and Gene Expressions of Female Giant Freshwater Prawn (Macrobrachium rosenbergii) after Dietary Administration of Medroxyprogesterone Acetate

Abstract One of the problems in giant prawn cultivation is female giant prawns laying eggs during rearing. They will incubate their eggs for three weeks so that the energy from the expected feed for growth is used for egg development and other reproductive activities. Giving MPA hormone to giant prawns either by injection or oral could inhibit gonadal maturation and increase growth rate. The maturation process of the prawn ovary consists of the activation of some complex cellular mechanisms involving genes that regulate the stages of oocyte development. This study aimed to evaluate the response of gonadal maturity and the expression of the MrvWD-Kazal gene in giant prawns fed with a diet containing MPA hormone. The design used in this study was a completely randomized design with four treatments and five replications. The treatments were feeding a diet added with MPA with a concentration of 0 mg.kg-1 feed as control (K), 50 mg.kg-1 feed (P1), 100 mg.kg-1 feed (P2), and 150 mg.kg-1 feed (P3). MPA hormone at a concentration of 50-150 mg/kg feed could inhibit the gonadal maturation of female prawns. In 100 mg/kg of feed concentration showed the lowest gene expression level, indicating an inhibition of gonadal maturation molecularly. The administration of MPA hormone through the feed is a recommended method of aquaculture because it is more applicable and effective than by injection, even though it has a non-uniform impact on each individual. Highlight Research Administration of MPA hormone through the feed to female giant freshwater prawns can inhibit the level of gonad maturity. Expression of von Willebrand factor D (vWD) – Kazal gene were analyzed in different levels of prawn maturity Gonadosomatic index and gonadal histology confirmed that different levels of administration of MPA hormone through the feed could affect the gonad development. The administration of MPA hormone through the feed is a recommended method for aquaculture because it is more applicable and effective to inhibit early maturation of prawns.

FoxH1 Represses the Promoter Activity of cyp19a1a in the Ricefield Eel (Monopterus albus).

Forkhead box H1 (FoxH1) is a sexually dimorphic gene in Oreochromis niloticus, Oplegnathus fasciatus, and Acanthopagrus latus, indicating that it is essential for gonadal development. In the present study, the molecular characteristics and potential function of FoxH1 and the activation of the cyp19a1a promoter in vitro were evaluated in Monopterus albus. The levels of foxh1 in the ovaries were three times higher than those in the testes and were regulated by gonadotropins (Follicle-Stimulating Hormone and Human Chorionic Gonadotropin). FoxH1 colocalized with Cyp19a1a in the oocytes and granulosa cells of middle and late vitellogenic follicles. In addition, three FoxH1 binding sites were identified in the proximal promoter of cyp19a1a, namely, FH1 (-871/-860), FH2 (-535/-524), and FH3 (-218/-207). FoxH1 overexpression significantly attenuated the activity of the cyp19a1a promoter in CHO cells, and FH1/2 mutation increased promoter activity. Taken together, these results suggest that FoxH1 may act as an important regulator in the ovarian development of M. albus by repressing cyp19a1a promoter activity, which provides a foundation for the study of FoxH1 function in bony fish reproductive processes.