Phoresy is an interspecies interaction that facilitates spatial dispersal by attaching to a more mobile species. Hitchhiking species have evolved specific traits for physical contact and successful phoresy, but the regulatory mechanisms involved in such traits and their evolution are largely unexplored. The nematode Caenorhabditis elegans displays a hitchhiking behavior known as nictation during its stress-induced developmental stage. Dauer-specific nictation behavior has an important role in natural C. elegans populations, which experience boom-and-bust population dynamics. In this study, we investigated the nictation behavior of 137 wild C. elegans strains sampled throughout the world. We identified species-wide natural variation in nictation and performed a genome-wide association mapping. We show that the variants in the promoter of nta-1, encoding a putative steroidogenic enzyme, underlie differences in nictation. This difference is due to the changes in nta-1 expression in glial cells, which implies that glial steroid metabolism regulates phoretic behavior. Population genetic analysis and geographic distribution patterns suggest that balancing selection maintained two nta-1 haplotypes that existed in ancestral C. elegans populations. Our findings contribute to further understanding of the molecular mechanism of species interaction and the maintenance of genetic diversity within natural populations.

Steroid hormones are responsible for coordinating many aspects of biological processes in most multicellular organisms, including insects. Ecdysteroid, the principal insect steroid hormone, is biosynthesized from dietary cholesterol or plant sterols. In the last 20 years, a number of ecdysteroidogenic enzymes, including Noppera-bo, Neverland, Shroud, Spook/Spookier, Cyp6t3, Phantom, Disembodied, Shadow, and Shade, have been identified and characterized in molecular genetic studies using the fruit fly Drosophila melanogaster. These enzymes are encoded by genes collectively called the Halloween genes. The transcriptional regulatory network, governed by multiple regulators of transcription, chromatin remodeling, and endoreplication, has been shown to be essential for the spatiotemporal expression control of Halloween genes in D. melanogaster. In this review, we summarize the latest information on transcriptional regulators that are crucial for controlling the expression of ecdysteroid biosynthetic enzymes and their roles in insect development.

Modes of mammalian reproduction are diverse and not always conserved among related species. Progesterone is universally required to supports pregnancy but sites of synthesis and metabolic pathways vary widely. The steroid metabolome of mid-to late gestation was characterized, focusing on 5α-reduced pregnanes in species representing the Perissodactyla, Cetartiodactyla and Carnivora using mass spectrometry. Metabolomes and steroidogenic enzyme ortholog sequences were used in heirarchial analyses. Steroid metabolite profiles were similar within orders, whales within cetartiodactyls for instance, but with notable exceptions such as rhinoceros clustering with goats, and tapirs with pigs. Steroidogenic enzyme sequence clustering reflected expected evolutionary relationships but once again with exceptions. Human sequences (expected outgroups) clustered with perissodactyl CYP11A1, CYP17A1 and SRD5A1 gene orthologues, forming outgroups only for HSD17B1 and SRD5A2. Spotted hyena CYP19A1 clustered within the Perissodactyla, between rhinoceros and equid orthologues, whereas CYP17A1 clustered within the Carnivora. This variability highlights the random adoption of divergent physiological strategies as pregnancy evolved among genetically similar species.

BACKGROUND: The clupeoid fishes are ecologically and commercially important fish species worldwide that exhibit a high level of population fluctuation, accompanied by alteration of reproductive traits. However, knowledge about their reproductive physiology in order to understand mechanisms underlying such population dynamics is limited. The endocrine system along with the brain-pituitary-gonadal (BPG) axis is critical for regulating reproduction. The aims of this study were to provide transcript data and genes related to the BPG axis, and to characterize the expression profiles of ovarian steroidogenesis-related genes in the Japanese sardine (Sardinops melanostictus, Clupeidae).
RESULTS: RNA sequencing was performed using the sardine brain, pituitary, and gonad in both sexes. A total of 290,119 contigs were obtained and 115,173 non-redundant ORFs were annotated. The genes differentially expressed between ovary and testis were strongly associated with GO terms related to gamete production. The tissue-specific profile of the abundance of transcripts was characterized for the major regulators in the BPG axis, such as gonadotropin-releasing hormone, gonadotropin, and steroidogenic enzyme. By comparing between ovary and testis, out of eight different 17β-hydroxysteroid dehydrogenase (Hsd17b) genes identified, higher hsd17b7 expression was found in testis, whereas higher expression of hsd17b8, hsd17b10, hsd17b12a, and hsd17b12b was found in ovary. The cDNAs encoding key endocrine factors in the ovarian steroidogenic pathway were cloned, sequenced, and quantitatively assayed. In the pituitary, follicle-stimulating hormone beta peaked during vitellogenesis, while luteinizing hormone beta peaked at the completion of vitellogenesis. In the ovary, follicle-stimulating hormone receptor and luteinizing hormone receptor were upregulated from mid- to late phase of vitellogenesis. Furthermore, three steroidogenic enzyme genes (cyp11a1, cyp17a1, and cyp19a1a) gradually increased their expression during ovarian development, accompanying a rise in serum estradiol-17β, while 3β-hydroxysteroid dehydrogenase and steroidogenic acute regulatory protein did not change significantly.
CONCLUSIONS: This is the first report of deep RNA sequencing analysis of Japanese sardine, in which many key genes involved in the BPG axis were identified. Expression profiles of ovarian steroidogenesis-related genes provide a molecular basis of the physiological processes underlying ovarian development in the sardine. Our study will be a valuable resource for clarifying the molecular biology of clupeoid fishes.

UNASSIGNED: Aberrant cortical adrenal tissues are not generally identified in adults. Herein, we present a very rare case of an ectopic adrenal tumor located in the renal hilum that caused gross hematuria.
UNASSIGNED: A 33-year-old man suddenly presented with asymptomatic gross hematuria. Abdominal computed tomography revealed a 35-mm mass in the left renal hilum encroaching the renal vein. Following the surgical removal with frozen section of the mass, his gross hematuria immediately improved. Pathological analysis of the specimen revealed the features adrenal adenoma. Immunohistochemical staining for key steroidogenic enzymes confirmed the adrenocortical origin without excessive hormone production.
UNASSIGNED: This is the first case of an ectopic adrenocortical adenoma in the renal hilum that caused gross hematuria without hormonal symptoms.

BACKGROUND: Androgen deprivation therapy (ADT) is a standard treatment for advanced prostate cancer (PCa). However, PCa recurrence and progression rates during ADT are high. Until now, there has been no evidence regarding when progression begins. This study evaluated the gene expression of intraprostatic androgen receptor (AR) and steroidogenic enzymes in the early stages of ADT.
METHODS: Prostate tissue samples were taken from PCa patients with urinary retention who received ADT (ADT-PCa; n = 10) and were further subgrouped into ADT ≤12 months (n = 4) and ADT > 12 months (n = 6). The ADT-PCa tissues were then compared with BPH (n = 12) and primary (no treatment) PCa tissues (n = 16). mRNA for gene expression analysis of AR and steroidogenic enzymes was extracted from formalin-fixed paraffin embedded (FFPE) tissues and analyzed by real-time PCR. Protein expression was evaluated by immunohistochemistry with specific antibodies.
RESULTS: AR gene expression was higher in the ADT-PCa group than in the BPH or primary PCa group. Both the ADT ≤12 and > 12 months subgroups had significantly higher relative gene expression levels of AR (p < 0.01 and 0.03, respectively) than the primary PCa group. In the ADT-PCa group, AR protein expression showed an increasing trend in the ADT ≤12 months subgroup and was significantly elevated in the ADT > 12 months subgroup compared with the PCa group (100%; p < 0.01). Half (50%) of the patients in the ADT ≤12 months subgroup were found to have upregulation of AR, and one showed upregulation beginning at 3 months of ADT. A trend toward elevated relative gene expression of SRD5A3 was also apparent in the ADT groups.
CONCLUSIONS: AR and steroidogenic enzymes are upregulated in ADT-PCa patients as early as 3 months, without PSA elevation. Steroidogenic enzymes, particularly SRD5A3, were also upregulated before PSA rose.

In adrenocortical pathology, it is important to localize the sites of steroid biosynthesis in order to obtain a better understanding of steroid metabolism. Previous morphological techniques, including light- and electron-microscopical examination, histochemistry, and immunohisto-chemistry of steroids, as well as biochemical studies, could not satisfactorily demonstrate which types of cortical cells produce which steroid hormones. Recent purification and characterization of specific steroidogenic enzymes, such as cytochrome P-450, that are involved in adrenal steroid biosynthesis have made it possible to generate specific antibodies and DNA probes against the enzymes that catalyze specific reaction(s) in the complicated biochemical cascade of steroidogenesis. By employing these antibodies and DNA probes, it has became possible to detect the expression of specific steroidogenic enzymes in surgically resected human adrenal cortex and its disorders. This can indicate the site(s) of specific steroid hormone(s) catalyzed by the expressed enzymes.

Trimethyltin (TMT) is widely used as a plastic heat stabilizer and can cause severe toxicity. Here, the effects of TMT on testosterone production by adult Leydig cells and the related mechanisms of action were investigated. Eighteen adult male Sprague Dawley rats (56 days old) were randomly divided into 3 groups and given intraperitoneal injection of TMT for 21 consecutive days at the doses of 0 (vehicle control), 5, or 10 mg/kg/d. After treatment, trunk blood was collected for hormonal analysis. In addition, related gene and protein expression in testes was detected. At 10 mg/kg, TMT significantly reduced serum testosterone levels but increased serum luteinizing and follicle-stimulating hormone levels. The messenger RNA and protein levels of luteinizing hormone/chorionic gonadotropin receptor, steroidogenic acute regulatory protein, cytochrome P450 17-hydroxylase/17,20-lyase, follicle-stimulating hormone receptor, and SRY box 9 were significantly lower in the TMT-treated testes than in controls. Immunohistochemical study showed that TMT decreased adult Leydig cell number. In conclusion, these findings indicate that TMT reduced adult Leydig cell testosterone production in vivo by directly downregulating the expression of steroidogenic enzymes and decreasing adult Leydig cell number in the testis.

High temperature decreases the egg number, ovarian weight, and hierarchical follicle number. In the present study, we investigated the effect of high temperature on the quality of eggs of adult female quails. Laying quail were raised under a standard thermal condition of 25 °C until exposed to an elevated temperature of 34 °C (experimental) or maintained at 25 °C (control) from 12:00 to 16:00 for 10 consecutive days. Weight and number of eggs were measured; serum and the largest follicles were collected and used for hormone measurement. Ovaries and adrenals were collected for expression analysis of 3β- and 17β-HSD, genes encoding steroidogenic enzymes. Egg weight slightly decreased with an increase in the treatment time in the heat-challenged group; the egg weight significantly decreased in the heat treatment group than in the control group during the last 2 days of experiment (P < 0.05). The laying rate showed no difference during the experimental period but significantly decreased on the last day in the heat treatment group. In the experimental group the ovaries and oviducts were lighter (P < 0.05) and the hierarchical follicle number and ovarian weight decreased (P < 0.05) compared to the control group. Although serum corticosterone level significantly increased after heat challenge (P < 0.05) and immediately recovered to the normal level, yolk immunoreactive corticosterone in the hierarchical follicle (F1, F2, F3) significantly increased (P < 0.05). The expression level of 17β-HSD showed no changes in the ovary but significantly increased in adrenals (P < 0.05). Our findings indicate that the effects of heat challenge on the maternal ovary in the quail are mediated through the adrenal function.

Microminipigs have become an attractive animal model for the toxicology- and pharmacology-related studies because of their manageable size. In this study, the development of the testicular interstitium and steroidogenesis in microminipigs, from 0 to 12 months of age, were investigated. Testicular interstitium was mostly composed of two types of Leydig cells (large and small Leydig cells) and a few macrophages and mast cells. Large Leydig cells were observed in the peritubular area throughout all the ages. Small Leydig cells were present in the interlobular and subcapsular areas at an early age and then gradually converted into large Leydig cells. Testicular composition of the Leydig cells began to increase after 3 months of age, when spermatogenesis was completed, and reached approximately 35% at 12 months. Steroidogenic enzymes in Leydig cells were detected by immunohistochemistry from 0 month of age. Serum testosterone levels increased substantially from 1.5 to 4.5 months of age, which coincided well with the age of sexual development previously reported in microminipigs. Because the interstitial space of the testis has dramatic variations between species, the basic information obtained in the present study will be a useful reference for all the future toxicity evaluations in microminipigs.