Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P01178 (oxytocin)
 15,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In an attempt to delineate the nature of the immunoreactive neurophysins in oat cell carcinomas of the lung with ectopic vasopressin production, tumor neurophysins were characterized by gel filtration and by electrophoresis. In all of the five tumor tissues, activities of both vasopressin and nicotine-stimulated neurophysin (NSN) determined by radioimmunoassay were demonstrated. A small amount of oxytocin as well as estrogen-stimulated neurophysin was detected in three of the tissues. When tissue extract was subjected to Sephadex G-50 gel filtration in 0.2 N acetic acid, the major portion of immunoreactive NSN emerged in the fractions corresponding to the molecular size of 10,000. The migration pattern of NSN in these fractions on electrophoresis was qualitatively the same as that of NSN extracted from human posterior pituitary glands. In addition to this major neurophysin, immunoreactive NSN with the molecular size of 20,000 was consistently demonstrated in three tumor extracts. This high molecular weight form of neurophysin represented 6.5--8.7% of total NSN immunoactivities in each tumor extract and its elution profile was not changed when analyzed under denaturating conditions in 6 M guanidine hydrochloride. On electrophoresis, it migrated near the gamma globulin region; however, the peak was broad suggesting that it consists of more than two different molecular populations. A substantial portion of the high molecular weight NSN appears to be a glycoprotein judging from its binding to concanavalin A. When the high molecular weight from of neurophysin was incubated with trypsin, essentially all of the activities were converted into NSN with the molecular size of 10,000. Moreover, an equimolar amount of vasopressin was liberated after the treatment, the elution pattern of which closely resembled that of synthetic arginine vasopressin. When a lower concentration of trypsin was used, some of the 20,000-dalton neurophysin exhibited activities of both NSN and vasopressin. Since the antivasopressin serum used in this study appeared to be directed toward the ring portion side of vasopressin, these results suggest that this 20,000-dalton neurophysin is, in all probability, a common precursor to vasopressin and neurophysin, and that vasopressin may be located in the middle of the precursor molecule.
 ...
PMID:Nature of the immunoreactive neurophysins in ectopic vasopressin-producing oat cell carcinomas of the lung. Demonstration of a putative common precursor to vasopressin and neurophysin. 626 3

The rat arginine vasopressin-neurophysin precursor gene has been isolated from a genomic library cloned in lambda phage Charon 4A. Restriction mapping and nucleotide sequence analysis demonstrated that the gene is 1.85 kilobase pairs long and contains two intervening sequences located in the protein coding region. Exon A encodes a putative signal peptide, the hormone arginine vasopressin and the variable N terminus of the carrier protein neurophysin, exon B encodes the highly conserved middle part of neurophysin and exon C its variable C terminus together with glycoprotein. Thus, the three functional domains of the percursor - arginine, vasopressin, neurophysin, glycoprotein - are encoded on three distinct exons.
 ...
PMID:Structural organization of the rat gene for the arginine vasopressin-neurophysin precursor. 631 16

A glycoprotein of neurohypophysial origin was found to have cofractionated with FSH prepared from pituitary glands of the green turtle, Chelonia mydas. Antiserum raised against this preparation contained high antibody titres and affinity for the neurohypophysial component and allowed development of a specific radioimmunoassay to monitor its purification and distribution in the brain. Immunocytochemistry revealed that the glycoprotein was concentrated in the pars nervosa and associated nerve tracts passing through the median eminence to the supraoptic and paraventricular nuclei; similar distributions were observed in turtles and rats. The antiserum to the turtle material bound radiolabelled rat vasopressin (VP)-neurophysin and precipitated precursors of this neurophysin, but it did not cross-react with rat oxytocin-neurophysin. An amino-terminal alanine was also consistent with the structure of rat VP-neurophysin, but the turtle molecule was larger than the corresponding rat molecule. Limited tryptic digests of the turtle glycoprotein contained two components, one of which bound to lysine VP. Both components contained carbohydrate, but only the one which bound to VP cross-reacted in a radioimmunoassay for rat VP-neurophysin. The apparent surge in plasma immuno-FSH at the time of oviposition previously described in the turtle probably represented release of a neurophysin-like 'carrier' molecule associated with secretion of the neurohypophysial hormone (e.g. arginine vasotocin; AVT) responsible for oviduct contractility. These data suggest that the neurohypophysial glycoprotein represents a partially processed AVT precursor and provide the first biochemical evidence of a mammalian-like biosynthetic pathway for neurohypophysial hormones in a non-mammalian species.
 ...
PMID:Presence of a neurophysin-like precursor in the green turtle (Chelonia mydas). 643 86

Using a combination of in vitro methodology, including cell-free translation, two-dimensional peptide mapping and recombinant DNA techniques, the structure of the precursors of the hypothalamic nonapeptide hormones vasopressin and oxytocin has been elucidated. Both hormone precursors are model cellular polyproteins in that they comprise several different entities within the same polypeptide molecule. In each precursor, the nonapeptide hormone follows immediately the signal peptide and is, in turn, attached to its respective carrier neurophysin. The vasopressin precursor also includes a pituitary glycoprotein at its C-terminus. The posttranslational processing of the precursors to set free the nonapeptide hormones is thus a critical regulatory step, which can in part be simulated in the quasi in vivo system of the Xenopus laevis oocyte. The preprohormones to vasopressin and oxytocin illustrate well the convenience of the in vitro experimental approach in understanding the function of the peptidergic neuron.
 ...
PMID:Vasopressin and oxytocin precursors as model preprohormones. 662 4

In the subfornical organ of Rana esculenta, three basic structural elements can be demonstrated by light microscopic and immunohistological techniques used for the demonstration of products of the neurosecretory system. These elements are: (i) neurones and their processes, which the constituents of the subfornical organ proper, (ii) afferent axons of the preoptic nucleus, and (iii) subependymal cells with coarse processes. The vesicular inclusions of the two former structures correspond to the neurophysin vesicles with respect to their size, structure and reactivity. The vesicles of the subependymal cells belong to the same size class, possess a somewhat granular internal structure and react atypically after the application of the ultrahistochemical technique for the identification of neurophysin vesicles. Presumably, their content is a glycoprotein with a high proportion of cystine. The peptidergic axons of the preoptic nucleus projecting to the subfornical organ form neuroneuronal synapses.
 ...
PMID:Extrahypothalamic peptidergic neurosecretion. II. Neurosecretion in the subfornical organ of Rana esculenta L. 696 86

The supraoptic (SON) and paraventricular (PVN) nuclei of the lizard Liolaemus cyanogaster c. were studied by use of histochemical, immunocytochemical and electron microscopic methods. The immunofluorescence staining for neurophysin was applied to methacrylate-embedded material before and after treatment of the sections with urea and trypsin. Pseudoisocyanine was applied to sections previously used for immunocytochemistry. The ultrastructural study showed that the SON and PVN neurons posses neurosecretory granules (nsg), distributed throughout the perikaryon, and large (2 to 12 micrometers) electron-dense droplets located within dilatations of the cisternae of the rough endoplasmic reticulum. Whereas the perikaryon (nsg) and the secretory droplets are stainable with pseudoisocyanine, only the former displays immunoreactivity for neurophysin. However, after treating the sections with urea and trypsin, the same secretory droplets become immunoreactive. It is suggested that the secretory droplets are sites of storage for the precursor of neurophysin, and that the tryptic digestion either triggers its conversion into neurophysin or exposes its immunoreactive sites. Based on the ultrastructure and the histochemical behavior of the secretory droplets, it is also postulated that they contain, in addition to peptides, a glycoprotein component.
 ...
PMID:Ultrastructure and immunocytochemistry of neurons in the supraoptic and paraventricular nuclei of the lizard Liolaemus cyanogaster. Evidence for the intracisternal location of the precursor of neurophysin. 699 86

Polymerase chain reaction (PCR) primers designed to amplify bovine specific sequences of the arginine-vasopressin (ARVP), glycoprotein hormone alpha (CGA), cytochrome oxidase c subunit IV pseudogene (COXP), prochymosin (CYM), coagulation factor X (F10), inhibin beta A (INHBA), low density lipoprotein receptor (LDLR) and oxytocin (OXT) genes in hybrid cells were used in a search for single strand conformation polymorphisms. DNA from 75 animals comprising crossbred and 7 purebred breeds were analysed. ARVP, COXP, CYM, LDLR and OXT were found to be polymorphic while CGA, F10 and INHBA were not. Polymorphic regions were identified within 206 bp of exon 1 of ARVP, 582 bp of the pseudogene COXP, 253 bp of exon 9 of CYM, 519 bp of LDLR cDNA and 160 bp of the upstream regulatory region of OXT. This is the first report of bovine polymorphisms for these genes and an important step in our goal to incorporate type I comparative anchor loci into the bovine linkage map. Polymorphic loci were subsequently analysed in pedigreed full-sib families and shown to be inherited in a Mendelian fashion.
 ...
PMID:Single-strand conformation polymorphisms (SSCPs) detected in five bovine genes. 768 2

Familial central diabetes insipidus is an autosomal dominant disease caused by a deficiency of arginine vasopressin (AVP). We previously reported three distinct mutations in the AVP gene in Japanese familial central diabetes insipidus pedigrees that result in a substitution of Ser for Gly57 in the neurophysin-II (NPII) moiety of the AVP precursor, a substitution of Thr for Ala at the COOH-terminus of the signal peptide, and a deletion of Glu47 in the NPII moiety. In this study, we analyzed the AVP gene in two pedigrees by direct sequencing of the polymerase chain reaction-amplified DNA and found two novel mutations in exon 2, which encodes the central part of the NPII moiety of the precursor. The mutation in one pedigree was a C to A transition at nucleotide position 1891, which replaces Cys67 (TGC) with stop codon (TGA). As the premature termination eliminates part of the COOH domain of the NPII moiety and the glycoprotein moiety, the conformation of the truncated protein is likely to be markedly different from that of normal precursor. In another pedigree, a G to T transversion was detected at nucleotide position 1874, which substitutes polar Trp (TGG) for hydrophobic Gly62 (GGG). It is possible that mutated NPII molecules, as a consequence of a conformational change, cannot bind AVP or self-associate to form higher oligomer complexes. Interestingly, all mutations we have identified to date, with the exception of the signal peptide mutation, are located in exon 2, suggesting the importance of the highly conserved central part of the NPII molecules and/or the NPII moiety in the precursor for AVP synthesis.
 ...
PMID:Two novel mutations in the coding region for neurophysin-II associated with familial central diabetes insipidus. 771 10

The adult hypothalamo-neurohypophysial system, responsible for the secretion of the neurohormones, oxytocin, and vasopressin, undergoes reversible neuronal-glial and synaptic changes in response to stimulation (parturition, lactation, and osmotic stimulation). In the hypothalamus, these changes result in reduced astrocytic coverage of oxytocinergic somata and dendrites and concomitant increases in their GABAergic synapses; in the neurohypophysis, they lead to an enlarged neurovascular contact area. We discuss the possible role played by certain cell adhesion molecules, such as the highly sialylated isoform of the neural cell adhesion molecule, PSA-NCAM, the F3 glycoprotein, and the extracellular matrix molecule, tenascin, in such plasticity. The hypothalamo-neurohypophysial system continues to express high levels of these molecules during adulthood and they may serve as permissive factors to allow stimulus-induced structural remodelling to occur.
 ...
PMID:Adhesion molecules and structural plasticity of the adult hypothalamo-neurohypophysial system. 793 46

Inhibin and activin are best known as gonadal glycoprotein hormones but have a broad anatomical distribution. We previously described the central distribution ofinhibin/activin beta A- and beta B-subunit proteins in some neuronal cell bodies, fibers, and nuclei of the rat brain and reported a possible role for central activin in suckling-induced oxytocin secretion and corticotropin releasing factor release. In the present report, we mapped the detailed immunohistochemical localization of inhibin/activin alpha-, beta A-, and beta B-subunits throughout the rat brain to further clarify their central distribution. In addition, the localization and distribution of their corresponding mRNAs was assessed. The results are summarized as follows: 1) Both beta A- and beta B-subunit immunoreactivity are found in neuronal cell bodies in the nucleus of the solitary tract and the dorsal and ventral medullary reticular nuclei, and in fibers and terminals of known projection sites for these nuclei. 2) beta B-subunit immunoreactivity is localized in a group of perifornical neurons in the hypothalamus. 3) beta A-subunit immunoreactivity is present in discrete populations of neuronal cell nuclei scattered throughout the CNS. 4) mRNAs encoding each of the inhibin/activin subunits are expressed in all major brain regions as determined by S1 nuclease assay and in a variety of specific neuroanatomical sites as shown by in situ hybridization. The results suggest that central inhibin and activin proteins are produced in the brain where they may potentially serve inter- and intracellular functions in multiple systems.
 ...
PMID:Hybridization histochemical and immunohistochemical localization of inhibin/activin subunits and messenger ribonucleic acids in the rat brain. 882 Aug 78


<< Previous 1 2 3 4 5 Next >>