title: The olfactory organ of the trout Salmo trutta fario: a novel localization for a progestin receptor.
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.
authors.affiliation: Department of Biological and Environmental Sciences, University of Sannio, Via Port'Arsa, 11, Benevento 82100, Italy.
authors.forename: Ettore
authors.initials: E
authors.lastname: Varricchio
authors.forename: Elena
authors.initials: E
authors.lastname: Coccia
authors.forename: Rosalba
authors.initials: R
authors.lastname: Putti
authors.forename: Marina
authors.initials: M
authors.lastname: Paolucci
mesh_terms: D019326:17-alpha-Hydroxyprogesterone / Q000378:metabolism; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D015153:Blotting, Western; D002645:Chickens; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D003900:Desoxycorticosterone / Q000378:metabolism; D005260:Female; D006801:Humans; D006908:Hydroxyprogesterones / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D008970:Molecular Weight; D009833:Olfactory Pathways / Q000737:chemistry* / Q000502:physiology; D011485:Protein Binding; D011980:Receptors, Progesterone / Q000032:analysis* / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012487:Salmonidae / Q000235:genetics / Q000502:physiology*; D017422:Sequence Analysis, DNA
chemical_list: D000911:Antibodies, Monoclonal; D018076:DNA, Complementary; D006908:Hydroxyprogesterones; D011980:Receptors, Progesterone; C007433:17,20-dihydroxy-4-pregnen-3-one; D003900:Desoxycorticosterone; D019326:17-alpha-Hydroxyprogesterone