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How the growth hormone (GH)/insulin-like growth factor (IGF) system affects osmoregulation in basal vertebrates remains unknown. We examined changes in the expression of components of the GH/IGF axis and gill ion transporters during metamorphosis and following seawater (SW) exposure of sea lamprey. During metamorphosis, increases in gill nka and nkcc1 and salinity tolerance were accompanied by increases in pituitary gh , liver igf1 , gill ghr and igf1 , but not liver ghr. SW exposure of fully metamorphosed sea lamprey resulted in slight increases in plasma chloride concentrations after SW exposure, indicating a high level of SW tolerance, but no major changes in mRNA levels of gill ion transporters or components of the GH/IGF axis. Our results indicate that metamorphosis is a critical point in the lifecycle of sea lamprey for stimulation of the GH/IGF axis and is temporally associated with and likely promotes metamorphosis and SW tolerance. • The GH/IGF axis developed early in the vertebrate lineage. • Metamorphosis is key in the lifecycle of sea lamprey for stimulation of the GH/IGF axis. • The role of GH/IGF axis is osmoregulation evolved early in vertebrate evolution. • The GH/IGF axis in sea lamprey works similarly to that of teleost fishes. • In sea lamprey, gill ion secretion mechanisms develop prior to ocean entry. [ABSTRACT FROM AUTHOR]

The renewal of the natural resources is one of the most concerning aspects of modern farming. In animal production, there are many barriers breeders and researchers have to overcome to develop new practices to improve reproductive potential and hasten sexual maturation of the commercially viable species, while maintaining meat quality and sustainability. With the utilization of molecular biology techniques, there have been relevant advances in the knowledge of spermatogenesis, especially in mammals, resulting in new possibilities to control male fertility and the selection of desirable characteristics. Most of these discoveries have not been implemented in animal production. In this review, recent studies are highlighted on the molecular pathways involved in spermatogenesis in the context of animal production. There is also exploration of the interaction between environmental factors and spermatogenesis and how this knowledge may revolutionize animal production techniques. Furthermore, new insights are described about the inheritance of desired characteristics in mammals and there is a review of nefarious actions of pollutants, nutrition, and metabolism on reproductive potential in subsequent generations. Even though there are these advances in knowledge base, results from recent studies indicate there are previously unrecognized environmental effects on spermatogenesis. The molecular mechanisms underlying this interaction are not well understood. Research in spermatogenesis, therefore, remains pivotal as a pillar of animal production sustainability. • An adequate nutritional status is crucial to achieve normal spermatogenesis. • Environmental factors can modulate the inheritance of desirable characteristics. • Endocrine-disrupting chemicals disrupt both the endocrine and reproductive systems. • Epigenetic factors regulate spermatogenesis and embryo development in mammalians. [ABSTRACT FROM AUTHOR]

In insects that lay eggs in large clutches, yolk accumulation in each of the many ovarioles is restricted to the basal (terminal) oocyte, the one closest to the lateral oviduct. All succeeding (subterminal) oocytes remain small until the terminal oocytes finished their development and were ovulated into the oviduct. The major step regulating yolk uptake by terminal oocytes is the formation of gaps between cells of the follicle layer, a process termed patency. In the migratory as well as in the desert locust, patency is induced by a Patency Inducing Factor (PIF) produced by the lateral oviducts. PIF is secreted in all regions of the lateral oviducts and interacts with the basal follicle cells via the pedicel, a fine duct that connects an ovariole with the oviduct. By this mechanism, patency is triggered in the follicle cells of the terminal oocyte only, restricting yolk accumulation to the oocytes next to ovulation. In contrast to the previous hypothesis, juvenile hormone (JH) is not necessary to induce patency, rather JH amplifies the effect of PIF. [ABSTRACT FROM AUTHOR]

Abstract: Bone is a complex tissue, which has a number of mechanical and physiological functions. The maintenance and repair of bone is ensured by a constant cycle of turnover and remodelling. The control of this process is equally complex and is regulated by both mechanical and biological controls. This article outlines the normal physiology and regulation of bone and provides a basis for the understanding of both the pathogenesis and management of common disorders of bone and bone metabolism as well as an appreciation of specific pathways of pharmacological intervention. [Copyright &y& Elsevier]

Abstract: Environmentally induced phenotypic plasticity is common in nature. Hormones, affecting multiple traits and signaling to a variety of distant target tissues, provide a mechanistic link between environments, genes and trait expression, and may therefore well be involved in the regulation phenotypic plasticity. Here, we investigate whether in the tropical butterfly Bicyclus anynana temperature-mediated plasticity in egg size and number, with fewer but larger eggs produced at lower temperatures and vice versa, is under control of juvenile hormone, and whether different temperatures cause differences in egg composition. Female B. anynana butterflies showed the expected response to temperature, however, we found no evidence for an involvement of juvenile hormone. Neither haemolymph JH II and JH III titres nor vitellogenin levels differed across temperatures. The smaller eggs produced at the higher temperature contained relatively higher amounts of water, free carbohydrates and proteins, but relatively lower amounts of lipids. While these smaller eggs had a lower absolute energy content, total reproductive investment was higher at the higher temperature (due to a higher fecundity). Overall, our study indicates that temperature-mediated plasticity in reproduction in B. anynana is mechanistically related to a biophysical model, with oocyte production (differentiation) and oocyte growth (vitellogenesis) having differential temperature sensitivities. [Copyright &y& Elsevier]

Abstract: In this article, we provide a concise review of the past and current literature on the neglected influence of progesterone on male sexual behavior. Although there has been increased interest in all aspects of male sexual function, and the importance of androgens in the regulation of male copulatory behavior has long been well documented, knowledge of the role of progesterone on male sexual behavior is still patchy. Very little human data exist on this theme, and most of the literature concerns animal research, in particular reptiles and rodents. This review attempts to outline specific progesterone mechanisms involved in male sexual behavior, showing that this hormone plays a more relevant role in the control of male sexual behavior than commonly assumed. Exploring the neuroendocrine mechanisms of progesterone in the sexual behavior of males may provide insights into the regulation of sexuality in this gender. [Copyright &y& Elsevier]

Abstract: One of the major advances in the study of endocrine regulation of the mammary gland has been the development of techniques to obtain defined mutations in mice. The use of mice deficient in hormones, growth factors, receptors or transcription factors now allow to dissect hormonal pathways and to elucidate the specific role of the epithelium and the stroma. The study of temporal changes of global gene expression at each physiological stage is now possible by microarrays or proteomic analyses to profile gene or protein expressions, respectively. These approaches have been successful in demonstrating the huge number of genes that are differentially expressed in the murine and bovine mammary epithelial cells during pregnancy, lactation and involution. The next step to get the temporal and spatial assignement of gene function necessitate now the coordination of these technologies with accurate cellular biology approaches through in vivo and dynamic studies. [Copyright &y& Elsevier]

Abstract: The physiology of lactation includes development of the mammary gland from the foetal to the adult stage, further development during pregnancy and onset of lactation, with the accompanying metabolic and behavioural adaptation. At the onset of pregnancy the endocrine system undergoes dramatic changes. The growth of the mammary gland is stimulated by growth hormone and prolactin, adrenocortical steroids, oestrogens and progesterone, and that of the gastrointestinal (GI) tract by gastrin, CCK and secretin. The onset of lactation is accompanied by increases in the blood volume, cardiac output, mammary blood flow and blood flow through the GI-tract and liver, aiming to provide the udder with nutrients and hormones for regulation of milk synthesis. Food intake and distribution of nutrients to the mammary gland are partially regulated by hormones as well as the repartitioning of nutrients away from body stores towards the udder. To improve milk production, administration of growth hormone has been practised, but also much discussed. Besides central mechanisms, local mechanisms within the mammary gland regulate initiation of lactation, maintenance, regulation of blood flow and mammary gland cell apoptosis. Most of the milk in a filled dairy cow udder is stored in the alveolar compartments. The milk ejection reflex must be activated to gain access to the udder milk, i.e. oxytocin contracts the myoepithelial cells. Recent studies show that vasopressin may also elicit milk ejection. More efficient oxytocin release is achieved if the cows are fed during milking. Beyond milk let down, oxytocin influences maternal behaviour and metabolism. Furthermore, it has been indicated that suckling or milking activates a vagal reflex, which may link the milk production to the endocrine system of the GI-tract. The question has been raised whether the mammary gland is a supporting or consuming organ. [Copyright &y& Elsevier]

The effect of [His7]-corazonin on the abundance of antennal sensilla in the desert locust, Schistocerca gregaria, was investigated to test the hypothesis that injection of this neuropeptide would mimic a crowding effect. Solitarious locusts (reared in isolation) were injected with [His7]-corazonin at the 3rd nymphal instar and the numbers of sensilla on the 2nd, 8th and 14th antennal segments in the adult stage were compared with those for oil-injected solitarious controls or un-injected gregarious locusts (reared in group). The numbers of sensilla on these antennal segments were all reduced significantly after [His7]-corazonin injection compared with those for oil-injected controls, but similar to the values for gregarious individuals. Among the four major types of olfactory sensilla, coeloconic, trichoid, basiconic type A and basiconic type B, [His7]-corazonin injection influenced the abundance of all but the last type. The effect of [His7]-corazonin injection varied with the time of injection; the earlier the injection the larger the effects on the abundance of total antennal sensilla on the 8th segment, although the way in which the injection affected the abundance varied with the sensillum type. A hypothesis explaining how crowding affects the abundance of antennal sensilla and other phase-related characteristics through changes in [His7]-corazonin concentrations was proposed. [Copyright &y& Elsevier]

The effects of some endogenous hormones on the control of axillary bud development of pineapple Ananas comosus (L.) Merr. nodal segments cultivated in vitro were verified. Nodal segments with the apex (control) and decapitated nodal segments were used as explants and were cultured on hormone-free medium. Histological modifications occurring during the developmental process were also observed. Endogenous levels of indole-3-acetic acid (IAA) and four cytokinins (Cks) (isopentenyladenine (iP), isopentenyladenine 9-riboside (iPR), zeatin (Z) and zeatin riboside (ZR)) were quantified by means of high performance liquid chromatography (HPLC) and enzyme-linked immunosorbent assay (ELISA). During the first 4 h of culture, a marked reduction in the level of IAA (309%) of the decapitated nodal segment was detected and this coincided with the beginning of cell division in the leaf axil. Cks levels decreased during the first 12 h of culture in both explants. However, this reduction was 150% higher in the control, and occurred mainly due to a decrease in the level of ZR. The reduction in the level of IAA probably favored Cks biosynthesis and/or inhibited its degradation in the nodal tissue of the decapitated segment. After 16 h of culture, there was an increase in the level of IAA probably as a consequence of the establishment of the new auxin-producing shoot apex. After 1 d, a progressive increase in ZR occurred, suggesting that Z-type Cks have an important role in the leaf development of the new plant. Comparatively, auxin/total Cks ratio was always lower in the decapitated nodal segment throughout the process of the axillary bud development. [Copyright &y& Elsevier]

When insects molt, the exoskeleton is renewed under the controls of insect hormones via the biosynthesis and degradation of cuticle proteins. To understand the hormonal control of cuticle formation, we used the differential display method to look for stage-specific cuticle genes, and identified a novel cDNA named Bombyx mori Cuticle Protein GlyGlyTyr-repeat 1 (BMCPG1). Expression of BMCPG1 mRNA peaked sharply immediately after a pulse of ecdysteroid during the fourth molt and pre-pupal stages, concurrent with the expression of genes for FTZF1 and dopa decarboxylase. BMCPG1 was expressed only in the epidermis, but not in any other tissue. We cultured the larval epidermis and found that BMCPG1 expression is not induced by the continuous presence of ecdysteroid. Removal of ecdysteroid from the medium, which constitutes a pulse treatment, is required for the induction of BMCPG1 transcription. These results explain well the stage-specific expression of BMCPG1 by ecdysteroid in vivo. Based on its expression patterns and unique structure, we propose that BMCPG1 may be a novel component of epicuticle of B. mori, and is probably involved in cross-linking of proteins via its GGY repeats. [Copyright &y& Elsevier]

[Display omitted] • Molecular markers for saffron flower induction time have been identified. • Working models for hormone signalling pathways mediating flowering have been proposed. • Corm dormancy release is inhibited by abscisic acid, but induced by auxins. • Flower initiation is promoted by auxins and it may be inhibited by gibberellins. • Enlargement of scape during flower development is induced by gibberellins. The demand for saffron is expected to rise in the coming years due to its nutraceutical and medicinal properties. To cope with this, it will be necessary to develop a mechanised production of saffron. Upgrading the production methods requires accurate control of the flowering time in this species. Nevertheless, little is known about the control of flowering time in Crocus sativus L. The aim of this study is to gain insight into the floral induction regulatory networks operating in this species. A transcriptomic analysis was performed from saffron main buds in different stages of development. The identification of putative integrators of flowering time signals, like FT , as well as meristem identity genes, such as LFY and TFL1 , permitted the definition of the time of flowering induction of the buds, being able to use them as molecular markers. The identification of the transcripts encoded by a DROOPING LEAF-like (DL) gene is of particular relevance because this gene might be a novel factor for carpel specification in saffron. To elucidate the hormonal signalling networks working during flower induction, transcriptomic data were used, and the content of IAA, ABA and gibberellins was determined in competent and non-competent buds to flower, during the saffron life cycle. Our results suggested that ABA might be negatively regulating corm dormancy release, but its involvement in flower induction cannot be ruled out. ABI5 and the mediator of ABA regulated dormancy gene MARD1, could be key players of this pathway. In addition, a drop in GA 4 levels may also be a necessary, but insufficient, condition for floral induction and development. DELLA , TFL1 and PIF3 genes might be involved in the gibberellin pathway. Notably, IAA seems to be a positive regulator of the process, involving MP/ARF5 and ANT genes in the pathway. Taken together, these results pave the way to the unveiling of the regulatory networks controlling the vegetative-to-reproductive phase change in saffron. [ABSTRACT FROM AUTHOR]

In this study, we examined the effects of porcine growth hormone (GH) and cortisol on plasma insulin-like growth factor binding proteins (IGFBPs) in juveniles of three subspecies of Oncorhynchus masou (masu, amago, and Biwa salmon). Ligand blotting using digoxigenin-labeled human IGF-I was used to detect and semi-quantify three major circulating IGFBP bands at 41, 28, and 22 kDa, corresponding to IGFBP-2b, −1a, and -1b, respectively. GH increased plasma IGFBP-2b concentration in masu and Biwa salmon but suppressed it in amago salmon. Plasma IGFBP-2b levels were increased by cortisol in the three subspecies. Cortisol induced plasma IGFBP-1a in the three subspecies, whereas GH had a suppressive effect in masu and Biwa salmon. Sham and cortisol injections increased plasma IGFBP-1b levels after 1 day in masu and amago salmon, suggesting that IGFBP-1b is induced following exposure to stressors via cortisol. Increased IGFBP-1b levels were restored to basal levels when co-injected with GH in Biwa salmon, and the same trend was seen in masu and amago salmon. However, the suppressive effect of GH disappeared 2 days after injection in the three subspecies. Despite some differences among subspecies, the findings suggest that cortisol is a primary inducer of plasma IGFBP-1b; however, GH counteracts it in the short term. Therefore, GH has the potential to modulate the degree of increase in circulating IGFBP-1b levels during acute stress. Unlabelled Image • Hormonal regulation of plasma IGFBPs was examined in O. masou subspecies. • GH had a positive effect on plasma IGFBP-2b in masu and Biwa salmon. • Cortisol induced plasma IGFBP-1a and -1b. • GH counteracted cortisol action on IGFBP-1b in Biwa salmon. [ABSTRACT FROM AUTHOR]

• Sunburn is one of the most important damage in apple fruit production all over the world. • Physiological and metabolical disorders are triggered by sun radiation exposure. • New strategies for early detection in field have been developed. • Genomic and transcriptomic information will useful to understand the molecular mechanisms involved. Climate change negatively influences many human activities and one of the most affected is agriculture. In the apple industry, water availability, elevated temperatures and altered phenology will transform fruit production in traditional growing regions. Extended periods of intense solar radiation and high temperatures during the growing season cause problems in fruit quality increasing losses and reducing sustainability and profitability. Photooxidative and heat stress stimulate sunburn development on apple fruit in the field growing under increasingly stressful conditions. In particular, apples growing in semi-arid conditions are frequently exposed to high solar irradiance and elevated temperature during the growing season that promote the development of sun-related skin disorders. Furthermore, regions that have traditionally not faced sunburn pressure may begin to experience losses in this area. Apple cultivars differ in their susceptibility to sun damage, which is evidenced, in part, by the timing of symptom development and severity. Some studies attribute genotypic variation to physiological and morphological differences while others do to antioxidant-related metabolic differences between them. Here, we discuss the physiological and molecular progress and gaps in knowledge of sunburn damage and the development of sunburn resistance in apple fruit. This information will help develop stronger sunburn mitigation strategies and enhance breeding efforts to address challenges associated with sunburn in apple production. [ABSTRACT FROM AUTHOR]

Abstract: Blood glucose concentration represents the net flux of glucose entering and leaving the blood. Glucose is delivered to the blood from the liver following ingestion of carbohydrate, from the breakdown of glycogen (the storage form of glucose) and from endogenous glucose synthesis. Glucose is removed from the blood by a number of organs and tissues, notably the brain, skeletal muscle, liver and adipose tissue. With this variety of means of entry and exit from the blood, and the complications arising from too high or too low a glucose concentration, the regulation of blood glucose is complex. Many factors affect the delivery of glucose to, and its removal from, the blood. These include dietary carbohydrate and fat, the circulating free fatty acid concentration, exercise, hypoxia and the actions of several hormones. The postprandial blood glucose concentration is about 4-5.5 mmol/l or 70-100 mg/100 ml, but arterial concentrations vary throughout the day from about 3.5 mmol/l after exercise to 9 mmol/l following a meal. For the purposes of this article, it is the plasma fraction of blood glucose that is of most interest, because the plasma glucose concentration is the driving force behind the diffusion of glucose molecules across the capillary wall into the interstitial space. [Copyright &y& Elsevier]