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The photosynthetic differences between adult and juvenile Mediterranean plants were previously studied under field conditions, yet the corresponding differentiation of their photoprotective efficiency has not been sufficiently investigated. The present study aims to examine possible differences in the photoprotective potential between adults and juveniles of two native Mediterranean plants with distinct growth forms. Thus, the seasonal variations in individual carotenoids, electron transport rate (ETR), and non-photochemical quenching (NPQ) were monitored in fully exposed mature leaves from adults and juveniles of the winter deciduous tree Cercis siliquastrum L. and the evergreen sclerophyllous shrub Nerium oleander L. All plants were grown under apparently similar field conditions. In both species, juveniles displayed substantially lower ETR and increased NPQ values than adults in spring, with the differences intensifying during summer drought and diminishing in autumn. Concomitantly, juveniles showed significantly higher chlorophyll-based total carotenoids in spring and summer mainly due to the higher investment in xanthophyll cycle components (VAZ), in combination with an increased mid-day de-epoxidation state (DEPS) and partial retention of zeaxanthin in the dark. In N. oleander, although ETR was lower in juveniles during winter, NPQ was extremely low in both ages. In conclusion, juveniles exhibit enhanced photoprotection potential, especially in the summer, due to their reduced photochemical capacity. The photosynthetic superiority of adults during the favorable spring period may be attributed to the needs of the co-existing reproductive effort. [ABSTRACT FROM AUTHOR]

Black tiger shrimp (Penaeus monodon) is a commercially important species. It is reported to have low reproductive maturation rates in captivity. To improve the production of this species via sustainable aquaculture, genetic techniques are required to improve its maturation rates. However, to date, reports on P. monodon reproduction at a transcriptional level are limited. To address this, we conducted transcriptome sequencing of the ovaries and testes of P. monodon using high‐throughput sequencing to identify sex‐related pathways and genes. A total of 75.74 Gb of clean data were generated from nine gonadal tissue libraries. We obtained 62,276 unigenes with a mean length of 1452 bp and N50 of 2423 bp. A total of 11,411 significantly differentially expressed genes (DEGs) were identified between the testis and developed ovaries. Enrichment analysis of the DEGs identified 415 significantly enriched GO terms and 106 enriched KEGG pathways. Genes related to the P. monodon ovaries were enriched in the steroid biosynthesis, mRNA surveillance, nucleocytoplasmic transport, oxidative phosphorylation and DNA replication pathways. Five upregulated and five downregulated ovarian genes were confirmed using RT‐PCR. This investigation has thus identified important sex‐related functional genes, GO terms and pathways in P. monodon. In particular, we identified several important genes and pathways related to gonadal development, such as GnRH/GnRHR‐like, Hsp90, PCNA, cathepsin L, Wnt signalling pathway and ovarian steroidogenesis pathway, which provide important insights into the mechanism analysis and sex regulation of shrimp gonadal development. The results will provide reference data for future research into the reproductive biology of shrimp, which will aid in improved black tiger shrimp breeding in captivity. [ABSTRACT FROM AUTHOR]

The photosynthetic differences between adult and juvenile Mediterranean plants were previously studied under field conditions, yet the corresponding differentiation of their photoprotective efficiency has not been sufficiently investigated. The present study aims to examine possible differences in the photoprotective potential between adults and juveniles of two native Mediterranean plants with distinct growth forms. Thus, the seasonal variations in individual carotenoids, electron transport rate (ETR), and non-photochemical quenching (NPQ) were monitored in fully exposed mature leaves from adults and juveniles of the winter deciduous tree Cercis siliquastrum L. and the evergreen sclerophyllous shrub Nerium oleander L. All plants were grown under apparently similar field conditions. In both species, juveniles displayed substantially lower ETR and increased NPQ values than adults in spring, with the differences intensifying during summer drought and diminishing in autumn. Concomitantly, juveniles showed significantly higher chlorophyll-based total carotenoids in spring and summer mainly due to the higher investment in xanthophyll cycle components (VAZ), in combination with an increased mid-day de-epoxidation state (DEPS) and partial retention of zeaxanthin in the dark. In N. oleander, although ETR was lower in juveniles during winter, NPQ was extremely low in both ages. In conclusion, juveniles exhibit enhanced photoprotection potential, especially in the summer, due to their reduced photochemical capacity. The photosynthetic superiority of adults during the favorable spring period may be attributed to the needs of the co-existing reproductive effort.

Sexual maturation must occur on a controlled developmental schedule. In mammals, Makorin3 (MKRN3) and the miRNA regulators LIN28A/B are key regulators of this process, but how they act is unclear. In C. elegans, sexual maturation of the nervous system includes the functional remodeling of postmitotic neurons and the onset of adult-specific behaviors. Here, we find that the lin-28–let-7 axis (the ‘heterochronic pathway’) determines the timing of these events. Upstream of lin-28, the Makorin lep-2 and the lncRNA lep-5 regulate maturation cell-autonomously, indicating that distributed clocks, not a central timer, coordinate sexual differentiation of the C. elegans nervous system. Overexpression of human MKRN3 delays aspects of C. elegans sexual maturation, suggesting the conservation of Makorin function. These studies reveal roles for a Makorin and a lncRNA in timing of sexual differentiation; moreover, they demonstrate deep conservation of the lin-28–let-7 system in controlling the functional maturation of the nervous system.

Highlights • Androgen titers classically mediate aggressiveness and reproduction in vertebrates. • We tested whether juvenile hormone titers play a similar role in insects. • Juvenile hormone had a gonadotropic effect in Eupelmus vuilleti females. • Juvenile hormone affected female aggressiveness during contests for hosts. • Novel evidence is presented that juvenile hormone and androgens may have parallel actions. Abstract In vertebrates, titers of androgens such as testosterone are known to upregulate aggressive behaviors associated with reproduction. In insects, juvenile hormone (JH) is a good candidate for studying the flexibility of insect endocrine responses because it has important effects on both reproductive processes and behavior. JH has a gonadotropic effect across a broad range of insect species, increasing ovarian development in females, and may have a role in the regulation of aggressive behavior during competition. In Hymenoptera, the functions of JH have been studied in facultatively eusocial species such as polistine wasps, bumblebees, ants and bees. Surprisingly, no work has yet focused on the relationship between JH, reproduction and aggressiveness in a non-social Hymenoptera, although it may help to understand how JH actions have evolved across taxa with different degrees of sociality. Here, we explored how JH treatment influenced: i) female reproductive status, and ii) the intensity (aggressiveness) and resolution of conflict, in Eupelmus vuilleti (Hymenoptera: Eupelmidae), a solitary ectoparasitoid wasp in which females fight over hosts. We demonstrated that intra-abdominal injections of JH increased the number of mature eggs in females after 24 h. In addition, the number of aggressive behaviors displayed by females was affected by the interaction between JH treatment and the number of mature eggs in their abdomen, but mature egg load alone predicted the outcome of staged contests. Wasps were more aggressive when they had more ready-to-lay eggs, with this effect being stronger when females were injected with JH. Moreover, females won more frequently when they had higher mature egg load. Our results highlight how JH affects egg maturation and aggressive behaviors in Eupelmus vuilleti females. To our knowledge, this is the first study showing that hormone manipulation can modulate females' reproduction status and behavior during intraspecific competition over hosts in a non-social hymenopteran parasitoid. [ABSTRACT FROM AUTHOR]

Schistosomiasis is a human parasitic disease caused by flatworms of the genus Schistosoma. Adult female schistosomes produce numerous eggs that are responsible for the pathogenesis and transmission of the disease, and the maturation of female gonads depends on the permanent pairing of females and males. Signaling protein kinases have been proven to control female gonad differentiation after pairing; however, little is known about the roles of protein phosphatases in the developmental and reproductive biology of schistosomes. Here we explored 3 genes encoding catalytic subunits of serine/threonine protein phosphatase 1 (PP1c) that were structurally and evolutionarily conserved in Schistosoma japonicum. In situ hybridization showed transcripts of 3 Sj-pp1c genes mainly localized in the reproductive organs and tissues. Triple knockdown of Sj-pp1c genes by RNA interference caused stunted growth and decreased pairing stability of worm pairs, as well as a remarkable reduction in cell proliferation activity and defects in reproductive maturation and fecundity. Transcriptomic analysis post-RNA interference suggested that Sj-pp1c genes are involved in controlling worm development and maturation mainly by regulating cell proliferation, eggshell synthesis, nutritional metabolism, cytoskeleton organization, and neural process. Our study provides the first insight into the fundamental contribution of Sj-PP1c to molecular mechanisms underlying the reproductive biology of schistosomes. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effects of dietary supplementation of ferulic acid (FA) on reproductive tract weight (RTW), ovarian activity and serum concentrations of some metabolites and thyroid hormones of pre-pubertal hairbreed ewe lambs during the natural anestrous season. Twenty Dorper x Pelibuey crossbred ewe lambs (initial body weight = 28.5 ± 0.5 kg and age = 5.0 mo) were fed a basal diet and assigned to two treatments (n = 10) under randomized complete block design: FA supplementation to dosages of 0 (control) or 300 mg of FA/d animal −1 . Females were treated with FA during 34 d and then slaughtered to evaluate RTW and ovary. Blood samples were collected at days 1 and 34 to determine serum concentrations of metabolites (i.e. glucose, cholesterol, triglycerides, urea and total protein) and thyroid hormones. Final weight, dry matter intake, and serum concentrations of metabolites (except glucose) and thyroid hormones were unaltered by FA. Compared to control, FA-fed ewe lambs had lower ( P  = 0.05) serum glucose level but higher ( P  ≤ 0.05) RTW, ovarian mass, number of larger follicles and corpus luteum (CL). While percentage of ewe lambs with small follicles and number of small follicles per female did not vary, percentage of ewe lambs with large follicles and CL increased ( P  = 0.02) with FA. In conclusion, FA supplementation improves the reproductive tract development and ovarian activity of pre-pubertal hairbreed ewe lambs during the natural anestrous season. An improvement in functionality of the glucose-insulin system could be related with this benefic effect of FA. [ABSTRACT FROM AUTHOR]

Abstract: Transcriptomes of dissected brains from virgin alate and dealate mated queens from polygyne fire ants (Solenopsis invicta) were analyzed and compared. Thirteen genes were upregulated in mated queen brain, and nine were downregulated. While many of the regulated genes were either uncharacterized or noncoding RNAs, those annotated genes included two hexamerin proteins, astakine neuropeptide, serine proteases, and serine protease inhibitors. We found that for select differentially expressed genes in the brain, changes in gene expression were most likely driven by the changes in physiological state (i.e., age, nutritional status, or dominance rank) or in social environment (released from influence of primer pheromone). This was concluded because virgins that dealated after being separated from mated queens showed similar patterns of gene expression in the brain as those of mated queens for hexamerin 1, astakine, and XR_850909. Abaecin (XR_850725), however, appears upregulated only after mating. Therefore, our findings contribute to distinguish how specific gene networks, especially those influenced by queen primer pheromone, are regulated in queen ants. Additionally, to identify brain signaling pathways, we mined the fire ant genome and compiled a list of G‐protein‐coupled receptors (GPCRs). The expression level of GPCRs and other genes in the “genetic toolkit” in the brains of virgin alates and mated dealate queens is reported. [ABSTRACT FROM AUTHOR]

Life-history transitions require major reprogramming at the behavioral and physiological level. Mating and reproductive maturation are known to trigger changes in gene transcription in reproductive tissues in a wide range of organisms, but we understand little about the molecular consequences of a failure to mate or become reproductively mature, and it is not clear to what extent these processes trigger neural as well as physiological changes. In this study, we examined the molecular processes underpinning the behavioral changes that accompany the major life-history transitions in a key pollinator, the bumblebee Bombus terrestris. We compared neuro-transcription in queens that succeeded or failed in switching from virgin and immature states, to mated and reproductively mature states. Both successes and failures were associated with distinct molecular profiles, illustrating how development during adulthood triggers distinct molecular profiles within a single caste of a eusocial insect. Failures in both mating and reproductive maturation were explained by a general up-regulation of brain gene transcription. We identified 21 genes that were highly connected in a gene coexpression network analysis: nine genes are involved in neural processes and four are regulators of gene expression. This suggests that negotiating life-history transitions involves significant neural processing and reprogramming, and not just changes in physiology. These findings provide novel insights into basic life-history transitions of an insect. Failure to mate or to become reproductively mature is an overlooked component of variation in natural systems, despite its prevalence in many sexually reproducing organisms, and deserves deeper investigation in the future. [ABSTRACT FROM AUTHOR]

The present study aimed to describe serum anti-Müllerian hormone (AMH) patterns of ex situ male and female beluga to examine the influence of age (divided into 5-year categories) or sexual maturation and reproductive season. In males aged 5-9 years, AMH concentrations were significantly (P < 0.05) higher than those in all age categories exceeding 15 years and were not influenced by season (P = 0.57). AMH concentrations in females peaked in the 5-9-year age category during the breeding season and decreased (P < 0.05) after 9 years of age. Aged females displayed lower (P < 0.05) AMH concentrations than immature and mature animals and immature females secreted higher concentrations than mature animals (P = 0.03). For mature females, seasonal differences (P = 0.02) in AMH concentrations were detected, with females in the breeding season displaying higherAMHconcentrations than in the non-breeding season. This is the first timeAMHhas been characterised in a cetacean species and the first potential hormonal evidence of reproductive senescence in beluga. Further research is required to determine if this hormone can be used as a predictor of fertility for the species. [ABSTRACT FROM AUTHOR]

The timing of reproductive maturation is susceptible to hormonal and environmental influences, and variation in this timing can be partially attributed to the prenatal and post-natal environment. We examined associations between prenatal steroid exposure and the post-natal family environment on the variability in reproductive maturation timing in young marmosets ( Callithrix geoffroyi). Urine samples from pregnant females were analyzed for cortisol (CORT) and androgens (uA). Post-natal uA was measured in males to determine age (in days) of adult-like levels of androgens associated with spermatogenesis; post-natal pregnanediol glucuronide (PdG) was measured in females to determine age (in days) of first ovulation. Maternal, paternal, alloparental, and total care (carrying, grooming, and rejection/removals) of offspring were observed. Female offspring exposed to lower prenatal uA levels and higher paternal grooming and lower maternal rejection/removals showed later first ovulation, whereas female offspring exposed to higher prenatal uA showed earlier first ovulation. Male offspring showed earlier reproductive maturation as paternal grooming increased, regardless of first trimester uA exposure. Male offspring exposed to low prenatal uA levels showed earlier reproductive maturation as maternal rejections/removals increased. In offspring exposed to low prenatal CORT, high total carrying predicted earlier first ovulation in females, but later reproductive maturation in males. Total carrying duration did not affect timing of reproductive maturation in offspring exposed to high third trimester CORT levels. Our findings expand the evolutionary theory of socialization by demonstrating that the effect of post-natal family environment on timing of reproductive maturation depends on prenatal uA exposure and also influences reproductive maturation timing in male offspring. [ABSTRACT FROM AUTHOR]

In insects, juvenile hormone (JH) is critical for the orchestration of male reproductive maturation. For instance, in the male moth, Agrotis ipsilon , the behavioral response and the neuronal sensitivity within the primary olfactory centers, the antennal lobes (ALs), to the female-emitted sex pheromone increase with fertility during adulthood and the coordination between these events is governed by JH. However, the molecular basis of JH action in the development of sexual behavior remains largely unknown. Here, we show that the expression of the paralogous JH receptors, Methoprene-tolerant 1 and 2 (Met1 , Met2) and of the JH-inducible transcription factor, Krüppel homolog 1 (Kr-h1) within ALs raised from the third day of adult life and this dynamic is correlated with increased behavioral responsiveness to sex pheromone. Met1-, Met2- and Kr-h1-depleted sexually mature males exhibited altered sex pheromone-guided orientation flight. Moreover, injection of JH-II into young males enhanced the behavioral response to sex pheromone with increased AL Met1 , Met2 and Kr-h1 mRNA levels. By contrast, JH deficiency suppressed the behavioral response to sex pheromone coupled with reduced AL Met1 , Met2 and Kr-h1 mRNA levels in allatectomized old males and these inhibitions were compensated by an injection of JH-II in operated males. Our results demonstrated that JH acts through Met-Kr-h1 signaling pathway operating in ALs, to promote the pheromone information processing and consequently the display of sexual behavior in synchronization with fertility to optimize male reproductive fitness. Thus, this study provides insights into the molecular mechanisms underlying the hormonal regulation of reproductive behavior in insects. [Display omitted] • Methoprene-tolerant 1 and 2 and Krüppel homolog 1 are expressed in the antennal lobes. • The expression of Met1 , Met2 and Kr-h1 within antennal lobes raises during adulthood. • Silencing of Met1 , Met2 or Kr-h1 leads to altered sex pheromone-orientated flight. • Allatectomy reduces Met1 , Met2 and Kr-h1 mRNAs and sex pheromone-orientated flight. • The effect of allatectomy is partly compensated by injection of juvenile hormone. [ABSTRACT FROM AUTHOR]

Sex hormones play an important role in gametogenesis. During the breeding season, sex hormone levels in the sterile allotriploid crucian carp (3nAT) were significantly lower than those in the fertile diploid red crucian carp (2nRCC). Sex hormone rescue was performed to study the relationship between sex hormones and 3nAT sterility. For three months before breeding season, 3nAT females and males were fed the sex hormones estradiol and testosterone, respectively. During breeding season, hormone-rescued 3nAT fish (re-3nAT) showed normal reproductive behavior, and levels of estradiol in female re-3nAT and testosterone in male re-3nAT were similar to those of the diploid control (2nRCC). The vtg gene, which is associated with the hepatic synthesis of vitellogenin in the female, and the genes spef2, tekt1, and ift27 , which are associated with the formation of the sperm flagellum, were significantly upregulated in re-3nAT as compared to 3nAT. Under artificially assisted reproduction, re-3nAT individuals produced a few eggs of different sizes and sperm with abnormal structures. However, few individuals had insemination ability. Neither zygotes produced by self-crossing re-3nAT nor those produced by crossing re-3nAT with the haploid gametes produced by 2nRCC exhibited normal embryonic development. Thus, although sex hormone treatment led to the production of abnormal gametes by re-3nAT, viable offspring did not develop, meaning that re-3nAT remained sterile. These results indicated that sex hormones affected gamete maturation but were not the determinant of triploid sterility. • The sex hormone secretion of sterile allotriploid was abnormal. • Sex hormone treatment results in abnormal sterile gametes from allotriploid. • Sex hormone was not the decisive factor of triploid sterility. [ABSTRACT FROM AUTHOR]

The endocrine mechanism regulating reproduction of tiger shrimp, Penaeus monodon, is a field of topical interest, which is to be addressed in detail as control of reproduction in captivity is conditional for domestication. In this study, the titres of estradiol and progesterone in hemolymph, ovary and hepatopancreas during various reproductive phases of females were quantified using ELISA. Circulating concentration of hemolymph estradiol and progesterone in the endocrinologically induced (eyestalk ablated) females was also quantified. Additionally, the evidence for estradiol and progesterone receptors was provided using immunohistochemistry. Levels of progesterone in hemolymph and ovary were highest in the vitellogenic and ripe phases (P > 0.05). Conversely, in hepatopancreas significantly higher progesterone level was detected at immature phase (184.3 ± 2.3 pg/ml). Estradiol was highest in hemolymph (65.97 ± 0.8 pg/ml) and ovary (58.47 ± 0.7 pg/ml) at the early vitellogenic phase. In hepatopancreas, however, lowest level of estradiol was detected at the early vitellogenic phase (121 ± 0.38 pg/ml). Progesterone and estradiol receptor protein signals were predominantly found in the previtellogenic oocytes. These results suggest the possible involvement of vertebrate-type steroid in the reproductive maturation of P. monodon. [ABSTRACT FROM AUTHOR]

Identifying the causes of differential reproductive success is key to understanding natural selection and the forces of selection operating on animals. Here we present results from a 9-yr (2004-2012) study of female reproductive performance in relation to mother's age and rank, presence of immigrant males, rainfall, and fig fruit abundance in four groups of gray-cheeked mangabeys ( Lophocebus albigena) in Kibale National Park, Uganda. We found that females had a rank- and age-specific reproductive pattern, with high-ranking females maturing earlier, having their first births earlier, and exhibiting significantly slower reproductive aging than low-ranking females. We also found that both immigrant and resident males were associated with higher birth rates. Finally, we found that reproduction was aseasonal and did not correlate with rainfall, but that births correlated positively with the abundance of fruits of Ficus spp. Our results show broad similarities between arboreal, forest-dwelling gray-cheeked mangabeys and their more terrestrial, open habitat-dwelling papionin relatives in the importance of dominance rank in estrous cycle initiation, first reproduction, and reproductive aging. [ABSTRACT FROM AUTHOR]

This study was performed to clarify how the relative volume of saturated/unsaturated lipid and reproductive maturation relate to resistance to high temperature in the oceanic sea skaters, Halobates micans. Heat coma temperature (HCT) was measured in H. micans adults collected from a fixed sampling location (12°00'N, 135°00'E) in the western tropical Pacific Ocean. After measuring HCT, the specimen were dissected to measure the testes size and to determine the presence and number of oocytes in females. Bodies of the specimen were assessed by lipid analysis to evaluate saturated and unsaturated lipid content. A negative trend was seen between heat coma temperature and percentage of a saturated fatty acid, myristic acid (ratio of carbon number to number of double bonds=14:0) (Pearson's correlation test: r=-0.520, p=0.101). In contrast, a positive trend was detected between heat coma temperature and percentage of an unsaturated fatty acid, palmitoleic acid (16:1) (r=478, p=0.137). Young males with small testes showed lower heat coma temperatures, whereas females that showed relatively high heat coma temperatures of 36-40°C tended to have fewer mature oocytes in their ovaries than those that showed low heat coma temperatures of 30-34°C. As Halobates appears to exhibit embryonic diapause rather than adult diapause, males of H. micans may develop both testes and resistance to high temperature in the parallel as they grow. In females, a trade-off may occur between heat tolerance function and oogenesis in the oceanic sea skaters. [ABSTRACT FROM AUTHOR]

Abstract: Accurate and controlled methods to measure physiological stress are crucial to effectively monitor and assess the health of wildlife populations and evaluate resilience to external stressors. Glucocorticoids, particularly cortisol, are frequently used to measure stress in fish. While measurements of cortisol concentrations provide a powerful indicator of physiological stress, there are important considerations in accurately measuring and interpreting results. We assessed methods to capture and sample wild populations of salmonids and evaluated potential biases from sampling disturbance. We present results of a stress series and suggest approaches to mitigate bias associated with sampling disturbance. Studies on physiological stress in salmonids often focus on particular life stages (e.g. outward migration to marine waters, return migration to freshwater systems), or processes (e.g. fisheries interactions, spawning success), characterized by dramatic physiological challenges related to the developmental stage of the fish and the external environment. Such pressures influence baseline cortisol levels and complicate efforts to interpret the effects of additional external stressors. We present a profile for naturally occurring shifts in cortisol levels at migration, reproductive maturation, spawning, and senescence. This profile provides a crucial baseline for use as reference in evaluating physiological stress in Pacific salmon during crucial life stages. Our findings provide guidance for sampling wild salmonids and highlight the need for caution in interpreting cortisol in the context of physical challenges and physiological developments relevant to their complex life history. [Copyright &y& Elsevier]

Currently, there is widespread interest in establishing 25-hydroxy vitamin D (25OHD) level preventing a secondary elevation in parathyroid hormone (PTH). The aim of this study was to identify the 25OHD nadir resulting in a rise of PTH and to determine if this inflection point is weight- or race-specific during growth and development in peripubertal girls. A total of 104 normal (n = 61) and overweight (n = 43) African American (AA) and European American (EA) girls, 5 to 14 years of age, were included. Though AAs had lower 25OHD levels, there was no difference in PTH compared with EAs. A 25OHD concentration of 27.2 ng/mL (P < .01) was indicated to increase PTH in normal-weight girls, although a statistically significant level was not established in overweight girls. No race difference in inflection point was observed. These data suggest a potential influence of weight status on the 25OHD-PTH inflection point in peripubertal girls. Accordingly, on determination of 25OHD level reflecting optimal health, consideration of weight status appears to be important during this critical period of growth and development. [ABSTRACT FROM PUBLISHER]

Body condition and reproductive maturation are parameters of reproductive success that are influenced by sexual hormones rising in the circulation during the time of puberty. Various endocrine systems can be programmed by conditions experienced during early life. Stress for instance is supposed to be capable of influencing fetal development, leading to adjustments of offspring's later physiology. We examined whether prenatal stress (induced by exposure to strobe light) during early- to mid-gestation was capable of affecting later reproductive parameters in guinea pigs ( Cavia aperea f . porcellus). Therefore, we measured the levels of testosterone and progesterone from the age of day 12-124 in prenatally stressed (PS, n = 20) and unaffected control animals ( n = 24). Furthermore, we determined the timing of puberty and growth. Body weight development revealed significantly faster growth in PS females compared to control animals. The onset of first estrus was slightly earlier in PS females, however not significantly so. Cycle lengths and levels of progesterone differed between groups over the course of time with higher progesterone levels and more constant cycles among PS females compared to control females who displayed marked differences between first and subsequent cycles. Levels of testosterone did not differ between groups. We conclude that prenatal stress accelerates growth and maturity in females, but not in males. [ABSTRACT FROM AUTHOR]

Abstract: Reproductive maturation of wild caught female and male southern bluefin tuna (Thunnus maccoyii) (SBT) held under captive conditions at two locations were examined: (1) production SBT (n =132) held in sea cages located offshore of Port Lincoln, South Australia; and (2) broodstock SBT (n =24) held in an onshore breeding facility at Arno Bay, South Australia. With the exception of one large female specimen sampled from the sea cages offshore of Port Lincoln, there was no overlap in size range (fork length), and very little overlap in the range of whole body weight of the fish sampled at the two locations (production SBT 17 to 101kg and 98 to 155cm; broodstock SBT 97 to 152kg and 160 to 182cm). Production SBT were assumed to be aged 1 to at least 7years old and broodstock SBT were aged between 8 and 12years old. The production and broodstock SBT were generally heavier for a given length compared to that predicted for wild SBT and the broodstock SBT were younger in age for a given fork length compared to that determined for wild SBT. Therefore, predictions from wild stocks may not be a reliable indication of the age of captive reared fish or their capacity to reproduce in captivity. Gonadal histology showed that female and male production SBT were mostly sexually immature. Female and male broodstock SBT were sexually mature. Sexually mature female SBT were observed from 101kg in body weight and 155cm in fork length, while male SBT were sexually mature at a smaller size (51kg body weight and 128cm fork length) compared to female SBT. Gonadosomatic and gonad index generally increased with increasing stages of maturation for female and male SBT; however, there was no relationship between general condition index, fat-body index or hepatosomatic index and stages of maturation. Furthermore, the study showed that SBT sourced from the wild and held in the captive environment for up to 9years can achieve sexual maturity. The production SBT found at advanced stages of maturation indicates that future broodstock can be sourced directly from the Great Australian Bight without the need for long term holding. [Copyright &y& Elsevier]

Termites face significant and chronic intranidal selection pressures from parasites and pathogens that colonize their nests. They also encounter microbes outside their nest while foraging and during dispersal of winged primary reproductives to establish new colonies. The latter run the additional risk of becoming infected by a mating partner. Indeed, death of reproductives because of disease is a major cause of incipient colony failure and may favor prescreening prospective mates for signs of illness. To determine the role of disease on mate preference in termites, female primary reproductives of the Pacific dampwood termite Zootermopsis angusticollis (Hagen) simultaneously were presented with reproductive males that were either healthy or exhibiting a progression of symptoms associated with infection by the entomopathogenic fungus Metarhizium anisopliae (Metchnikoff Sorokin). We compared duration and frequency of female visits to healthy and infected males. In addition, we determined the physiological consequences for females exposed to fungal conidia, either directly or indirectly through their mate. Females showed no preference for healthy rather than infected males. Moreover, only directly-exposed females experienced negative physiological effects, having a reduced chance of survival, gaining less weight, developing fewer functional ovarioles, and producing significantly fewer vitellogenic oocytes than controls. Although there are important fitness-related costs of direct exposure, the lack of mate selection based on disease risk suggests that more imminent ecological pressures (e.g., predators, desiccation) override the need for a careful and time-consuming assessment of a potential mate's health. [ABSTRACT FROM AUTHOR]

The reproductive physiology of social insects is often highly responsive to social stimuli from nestmates, but the mechanisms underlying this sensitivity are usually poorly understood. The effect of varied social conditions on the endocrinology and ovarian maturation in maturing female primary reproductives of the dampwood termite Zootermopsis angusticollis Hagen is studied to better understand their developmental responses to conspecifics. Newly dealate queens are paired with a reproductive male, with another maturing female, or are allowed to mature in isolation. Developmental responses are tracked by monitoring rates of juvenile hormone (JH) production by corpora allata in vitro, haemolymph ecdysteroids titres and ovarian development after 5, 10, 15 and 30 days of maturation. Significant declines in rates of JH production rates are observed by days 5, 10 and 30, respectively, for females paired with males, left to mature in isolation or paired with a female. Ecdysteroid titres increase by day 5 and stay elevated in females nesting with males. By contrast, for CA from females that are isolated or paired with another female, the titres decline and stay low until at least day 15, but increase significantly by day 30. These hormonal differences correspond to differential rates of physiological maturation, with more rapid ovarian development occurring in females paired with a male, than in those nesting alone or with another female. The results suggest that JH and ecdysteroids modulate the ovarian response of alates to stimuli from nestmates during this period of maturation, and that JH and ecdysteroid titres may be regulated independently during this period of development. [ABSTRACT FROM AUTHOR]

Socioendocrinology is the study of the effect of the social environment on the interactions between hormones and behavior. Individuals have evolved a physiological flexibility that enables them to respond to their social surroundings in a manner that maximizes reproductive success. We present evidence that (a) males who have evolved to participate in infant care have different endocrine profiles around offspring from males who have not evolved to regularly participate in infant care, (b) the energetic costs of reproduction in both males and females creates conditions conducive to elevated levels of both stress and sex hormones, (c) adolescent subfecundity among females evolved as a mechanism fostering mate choice, (d) some primate species are probably facultative ovulators, and (e) endocrine suppression of subordinate males probably does not contribute to delayed onset of reproduction but does contribute to reduced access to females, which hampers progeny production. Hormones and behavior are inextricably intertwined in a feedback relationship that regulates each other. [ABSTRACT FROM AUTHOR]

The in situ growth, maturation and senescence of central California Iridaea cordata (Turner) Bory was studied. This ontogenetic progression was quantified by measuring development and growth of: i) individually tagged blades, and ii) populations of blades within cumulative (1-yr duration) and seasonal experimental plots. Greatest growth and longest life span were exhibited by winter-spring initiated blades, and were correlated with a rapid increase in irradiance, but not with either seawater temperature or nutrients. Tagging studies showed that reproductive maturation and senescence of blades occurred throughout the year, irrespective of date tagged, growth rate or size. Moreover, the majority of blades continued to elongate following maturation, and some matured within 3 mo of initiation at all seasons but winter. At the population level maturation took place primarily during summer-autumn when 90 ±2% of the population was mature. The majority of the population senesces or "dies back" during autumn-winter. It is concluded that in situ, the blades are derived almost totally via vegetative means involving perennation. This indirectly suggests that sexual reproduction or the success of sporeling development are marginal. Additionally, the species is perennial with annually deciduous blades, characterized by both rapid growth and maturation. [ABSTRACT FROM AUTHOR]

We assessed ovarian and endocrine function in 86 adolescents over a six month period. Postmenstrual estrone (E1) and estradiol-17 beta (E2) levels, premenstrual FSH levels and pre- and postmenstrual LH, testosterone (T) and androstenedione (A) levels decreased as the frequency of ovulation increased, while premenstrual E2, progesterone (P) and 17 alpha-hydroxyprogesterone levels increased. Both right and left ovarian volume and the per cent of multifollicular ovaries decreased with an increase in the frequency of ovulation. In the premenstrual phase P values correlated significantly with frequency of ovulation for FSH (r = -0.43: P less than 0.001), LH (r = -0.36: P less than 0.01), T (r = -0.31: P less than 0.05) and A (r = -0.26: P less than 0.05). Our data suggest that in the postmenarcheal period the progressive loss of immature endocrine and ovarian characteristics (high LH, FSH, and androgen levels and enlarged, multifollicular ovaries) is linked to an increasing number of ovulations. Progesterone plays a major role in the development of cyclic function characteristic of adult maturity. [ABSTRACT FROM AUTHOR]

Sexual maturation must occur on a controlled developmental schedule. In mammals, Makorin3 ( MKRN3 ) and the miRNA regulators LIN28A/B are key regulators of this process, but how they act is unclear. In C. elegans , sexual maturation of the nervous system includes the functional remodeling of postmitotic neurons and the onset of adult-specific behaviors. Here, we find that the lin-28-let-7 axis (the 'heterochronic pathway') determines the timing of these events. Upstream of lin-28 , the Makorin lep-2 and the lncRNA lep-5 regulate maturation cell-autonomously, indicating that distributed clocks, not a central timer, coordinate sexual differentiation of the C. elegans nervous system. Overexpression of human MKRN3 delays aspects of C. elegans sexual maturation, suggesting the conservation of Makorin function. These studies reveal roles for a Makorin and a lncRNA in timing of sexual differentiation; moreover, they demonstrate deep conservation of the lin-28-let-7 system in controlling the functional maturation of the nervous system., Competing Interests: HL, EV, RM, KK, DF, DP No competing interests declared, (© 2019, Lawson et al.)

Schistosomiasis is a human parasitic disease caused by flatworms of the genus Schistosoma. Adult female schistosomes produce numerous eggs that are responsible for the pathogenesis and transmission of the disease, and the maturation of female gonads depends on the permanent pairing of females and males. Signaling protein kinases have been proven to control female gonad differentiation after pairing; however, little is known about the roles of protein phosphatases in the developmental and reproductive biology of schistosomes. Here we explored 3 genes encoding catalytic subunits of serine/threonine protein phosphatase 1 (PP1c) that were structurally and evolutionarily conserved in Schistosoma japonicum. In situ hybridization showed transcripts of 3 Sj-pp1c genes mainly localized in the reproductive organs and tissues. Triple knockdown of Sj-pp1c genes by RNA interference caused stunted growth and decreased pairing stability of worm pairs, as well as a remarkable reduction in cell proliferation activity and defects in reproductive maturation and fecundity. Transcriptomic analysis post-RNA interference suggested that Sj-pp1c genes are involved in controlling worm development and maturation mainly by regulating cell proliferation, eggshell synthesis, nutritional metabolism, cytoskeleton organization, and neural process. Our study provides the first insight into the fundamental contribution of Sj-PP1c to molecular mechanisms underlying the reproductive biology of schistosomes.-Zhao, L., Lu, Z., He, X., Mughal, M. N., Fang, R., Zhou, Y., Zhao, J., Gasser, R. B., Grevelding, C. G., Ye, Q., Hu, M. Serine/threonine protein phosphatase 1 (PP1) controls growth and reproduction in Schistosoma japonicum.

Life-history transitions require major reprogramming at the behavioral and physiological level. Mating and reproductive maturation are known to trigger changes in gene transcription in reproductive tissues in a wide range of organisms, but we understand little about the molecular consequences of a failure to mate or become reproductively mature, and it is not clear to what extent these processes trigger neural as well as physiological changes. In this study, we examined the molecular processes underpinning the behavioral changes that accompany the major life-history transitions in a key pollinator, the bumblebee Bombus terrestris. We compared neuro-transcription in queens that succeeded or failed in switching from virgin and immature states, to mated and reproductively mature states. Both successes and failures were associated with distinct molecular profiles, illustrating how development during adulthood triggers distinct molecular profiles within a single caste of a eusocial insect. Failures in both mating and reproductive maturation were explained by a general up-regulation of brain gene transcription. We identified 21 genes that were highly connected in a gene coexpression network analysis: nine genes are involved in neural processes and four are regulators of gene expression. This suggests that negotiating life-history transitions involves significant neural processing and reprogramming, and not just changes in physiology. These findings provide novel insights into basic life-history transitions of an insect. Failure to mate or to become reproductively mature is an overlooked component of variation in natural systems, despite its prevalence in many sexually reproducing organisms, and deserves deeper investigation in the future., (© The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.)

Currently, there is widespread interest in establishing 25-hydroxy vitamin D (25OHD) level preventing a secondary elevation in parathyroid hormone (PTH). The aim of this study was to identify the 25OHD nadir resulting in a rise of PTH and to determine if this inflection point is weight- or race-specific during growth and development in peripubertal girls. A total of 104 normal (n = 61) and overweight (n = 43) African American (AA) and European American (EA) girls, 5 to 14 years of age, were included. Though AAs had lower 25OHD levels, there was no difference in PTH compared with EAs. A 25OHD concentration of 27.2 ng/mL (P < .01) was indicated to increase PTH in normal-weight girls, although a statistically significant level was not established in overweight girls. No race difference in inflection point was observed. These data suggest a potential influence of weight status on the 25OHD-PTH inflection point in peripubertal girls. Accordingly, on determination of 25OHD level reflecting optimal health, consideration of weight status appears to be important during this critical period of growth and development.