Characterization of a testicular 17α,20β-dihydroxy-4-pregnen-3-one (a spermiation-inducing steroid in fish) receptor from a teleost, Japanese eel (Anguilla japonica)11The nucleotide sequence data reported in this paper will appear in the DDBJ/EMBL/GenBank nucleotide sequence databases with accession number AB032075.
A cDNA encoding a nuclear 17alpha,20beta-dihydroxy-4-pregnen-3-one (17alpha,20beta-DP, spermiation-inducing hormone in fish) receptor (DPR) was, for the first time, isolated from an eel testis cDNA library. The amino acid sequence of DPR shows high homology with those of human and chicken progesterone receptors. The affinity of the bacterial recombinant DPR ligand binding domain protein for 17alpha,20beta-DP is higher than that of progesterone. In transfection experiments using COS7 cells, the DPR showed progestin-dependent activation of transcription. 17alpha,20beta-DP was the most effective activator of transcription. These results indicate that the cDNA encodes a functional eel DPR, and show that 17alpha,20beta-DP has a nuclear receptor-mediated action in eel testes.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.
"Phylogenetic analyses of these four proteins clearly indicate that they correspond to the Senegalese sole homologs of StAR, 3b-HSD, 17b-HSD and 20b-HSD. In addition, we identified a partial cDNA for the Senegalese sole PR with high homology to the nuclear receptor for 17,20b-P described in the eel and in other teleost species  . "
[Show abstract][Hide abstract] ABSTRACT: In male teleosts, testicular steroids are essential hormones for the regulation of spermatogenesis and their production is regulated by pituitary gonadotropins. In the Senegalese sole (Solea senegalensis), an economically important flatfish with semi-cystic and asynchronous spermatogenesis, the gonadotropic regulation of spermatogenesis, particularly regarding the production and regulation of testicular steroids, are not well understood. For this reason, we first cloned and characterized the response of several key genes for the production and action of testicular steroids to the in vivo administration of human chorionic gonadotropin (hCG) and, second, we investigated the transcriptomic effects of hCG in the Senegalese sole testis. We succeeded in cloning the full-length cDNAs for Steroidogenic Acute Regulatory protein (StAR), 3β-hydroxysteroid dehydrogenase (3β-HSD), 17β-HSD and 20β-HSD and a partial cDNA for the nuclear progesterone receptor. In this study we also identified a transcript encoding a protein with homology to StAR, which we named StAR-like, that could represent a new member of the StAR-related lipid transfer (START) family. All the cloned genes were expressed in the testis and their expression levels were significantly increased by the in vivo administration of hCG. The plasma levels of testosterone and 11-ketotestosterone also increased in response to hCG administration, likely as a result of the induction of the expression of steroidogenic enzymes by hCG. Furthermore, gene expression analysis by microarray identified 90 differentially expressed genes in the testis in response to hCG administration, including genes potentially involved in steroidogenesis, progression of spermatogenesis and germ cell maturation and cytoskeletal organization. Our results have identified for the first time a number of key genes involved in the regulation of steroid production and spermatogenesis in the Senegalese sole testis that are under gonadotropic control.
Full-text · Article · Feb 2011 · General and Comparative Endocrinology
"But, cortisol does not seem to be an agonist of these receptors (Pinter and Thomas, 1995; Zhu et al., 2003). In male Japanese eel, DOC also displayed a high affinity for a nuclear 17α-20ß-dihydroxyproges- terone (MIS) receptor in the testis and once more, cortisol did not bind or activate it (Todo et al., 2000). That steroid binding profile was also observed in sperm membrane progestogen receptor in Atlantic croaker Micropogonias undulatus (Thomas et al., 2005). "
[Show abstract][Hide abstract] ABSTRACT: Reproduction in vertebrates is controlled by the Hypothalamus-Pituitary-Gonad axis and the main hormone actions have been extensively described. Still, despite the scattered information in fish, accumulating evidence strongly indicates that corticosteroids play essential roles in reproductive mechanisms. An integrative approach is important for understanding these implications. Animal husbandry and physiological studies at molecular to organismal levels have revealed that these corticosteroids are regulators of fish reproductive processes. But their involvements appear strongly contrasted. Indeed, for both sexes, corticosteroids present either deleterious or positive effects on fish reproduction. In this review, the authors will attempt to gather and clarify the available information about these physiological involvements. The authors will also suggest future ways to prospect corticosteroid roles in fish reproduction.
Full-text · Article · Mar 2009 · Comparative biochemistry and physiology. Part A, Molecular & integrative physiology
"ePR1 and ePR2 are coexpressed in the spleen and testis where they are supposed to form heterodimers, cooperating in the regulation of progestin-responsive gene expression (Ikeichi et al., 2002). ePR1 and ePR2 mRNA from Anguilla japonica testis have been cloned and sequenced (Ikeichi et al., 2002; Todo et al., 2000). The derived aa composition showed proteins with an approximate mw of about 100 kDa. "
[Show abstract][Hide abstract] ABSTRACT: A progestin receptor (PR) has been detected in the olfactory organ of the trout Salmo trutta fario. The specificity of this receptor was high for 17alpha,20beta-dihydroxy-4-pregnen-3-one (17alpha,20beta-DP), but it also bound 17alpha-hydroxy-progesterone (17alpha-OHP) and 21-hydroxyprogesterone (21-OHP), even when present at low concentrations (10-fold in relative binding affinity assay). Progesterone (P) competed effectively at much higher concentrations (1,000-fold in relative binding affinity assay). Immunohistochemical studies carried out with three different monoclonal antibodies against human progesterone receptor (hPR), chicken progesterone receptor hinge region (cPR), and chicken progesterone receptor A/B domain (PR22), revealed that immunoreactivity was present in the epithelium of the olfactory organ of females and males of the trout Salmo trutta fario only against hPR. Western blotting showed two hPR immunoreactive bands of about 62 and 66 kDa. Finally, a portion of the cDNA of about 300 nucleotides extending over the DNA binding domain and the ligand binding domain was cloned and sequenced, revealing a high degree of sequence homology of the PR in Salmo trutta fario with the PR in other teleosts.
Full-text · Article · Jan 2009 · Microscopy Research and Technique