Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The pre- and post-Golgi processing of preprovasopressin and prepro-oxytocin was evaluated by microsequencing for incorporated radiolabel. 35S-Cysteine and 3H-fucose were microinjected into rat supraoptic nuclei (SON), and proteins and peptides related to the biosynthesis of vasopressin (VP) and oxytocin (OT) were isolated at various times from the supraoptic nuclei and neural lobe by employing a one-step procedure of high performance liquid chromatography (HPLC). These proteins and peptides were recognized through their binding to specific antibodies against VP, OT, and rat neurophysins (RNPs), and by their binding to ConA-Sepharose. Two immunoreactive glycoproteins related to VP biosynthesis were recovered from the SON and both contained fucose and had a 35S-cysteine placement consistent with the location of the hormone sequence at the N-terminus. SDS-electrophoresis revealed the major protein form to be 21,000 daltons and the minor protein form to be 19,000 daltons. One nonglycosylated protein of 16,000 daltons related to oxytocin biosynthesis was recovered from the SON, and this protein also had a 35S-cysteine placement consistent with an N-terminal OT sequence. These data provide the first sequential evidence that prior to, or shortly after, packaging in the Golgi the preprohormones of VP and OT have lost their entire leader-peptide structures.
 ...
PMID:Single-step isolation and sequencing of vasopressin and oxytocin precursors. 140 17

[35S]Cysteine has been injected into the supraoptic nuclei of normal rats and of animals given 7 micrograms colchicine into the cerebrospinal fluid to inhibit transport of neurosecretory granules. Analysis of extracts of the supraoptic nuclei 20 min or 6 h after isotope injections showed that (i) colchicine does not affect biosynthesis, i.e., incorporation of tracer into the common precursors of neurohypophyseal hormones and their associated neurophysins, and (ii) processing of precursors inside the arrested granules proceeds normally.
 ...
PMID:Analysis of the neurohypophyseal components accumulating in the supraoptic nucleus of the rat after injection of colchicine. 662 93

We have developed small-scale methods for the isolation and biochemical characterization of subcellular fractions from single guinea-pig posterior-pituitary glands. Secretory vesicles and coated microvesicles produced in this way were of similar purity to those isolated from large amounts of tissue by conventional ultracentrifugation. [35S]Cysteine injected into the hypothalamus was found in the soluble contents of secretory vesicles isolated from the neural lobes 24 h later. High-pressure liquid-chromatographic analysis revealed that the radiolabel was incorporated into the expected neurosecretory products (oxytocin, vasopressin and neurophysin) and also into a biosynthetic intermediate in the vasopressin system. The membranes of secretory vesicles were labelled with [3H]choline 24 h after its hypothalamic injection. Little or no [3H]choline could be demonstrated in coated microvesicles at this time, although these structures were labelled 5 days after injection. Stimulating hormone secretion by chronic dehydration produced a significant fall in [3H]choline content of the secretory-vesicle membranes without any transfer of label into coated microvesicles, suggesting that coated microvesicles are not involved in membrane retrieval in the neurohypophysis.
 ...
PMID:Membrane retrieval in the guinea-pig neurohypophysis. Isolation and characterization of secretory vesicles and coated microvesicles after radiolabel incorporation in vivo. 671 33

Cysteine-rich proteins were isolated from the hypothalamo-neurohypophyseal tract of dogs by high performance molecular weight chromatography. Trypsin digestion of these proteins produced a low molecular weight (LMW) peptide which was identified, by chemical and immunological assays, as (Arg8) vasopressin. There appear to be two forms of the precursor protein, one which has vasopressin immunoreactivity, and one which does not. Trypsin digestion of this latter protein produces high as well as LMW immunoreactivity. This suggests that the non-immunoreactive protein may be the precursor to the immunoreactive protein.
 ...
PMID:Direct detection of the vasopressin precursor. 736 54

[35S]Cysteine-labeled putative precursors for vasopressin-associated neurophysin (NP-VP) and oxytocin-associated neurophysin (NP-OT) were isolated from the supraoptic nuclei (SONs) of normal rats. Homozygous Brattleboro rats were deficient in one of these precursors, the NP-VP precursor. Direct support for the hypothesis that OT and its NP- and VP and its NP are synthesized from two separate macromolecular common precursors was obtained by limited proteolysis of the precursors with trypsin and identification of the fragments as NPs, VP, or OT by a number of criteria (14). In this paper, these common precursors designated propressophysin (precursor for NP-VP and arginine VP) and prooxyphysin (precursor for NP-OT and OT) were further characterized. Propressophysin was specifically bound by Concanavalin-A-Sepharose and was eluted by 0.2 M alpha-methyl mannoside, showing that it is glycosylated. In contrast, prooxyphysin does not appear to be glycosylated. Using [3H]fucose as label injected near the SONs, two proteins (mol wt, approximately 10,000) were identified, which appear to be derived from propressophysin, that are rapidly transported to the posterior pituitary of normal rats. These two proteins were absent in homozygous Brattleboro animals. Both propressophysin and prooxyphysin were bound by a NP-Sepharose affinity support. The binding was different from that of arginine VP or OT to NP, since it was independent of pH and was hydrophobic in nature. In addition to prooxyphysin, the SONs of homozygous Brattleboro rats also contained other [35S]cysteine-labeled protein (mol wt, 20,000) composed of a NP-like protein and NP-binding peptides. The tryptic peptides derived from these proteins were very different in their chromatographic (high performance liquid chromatography) properties than the tryptic peptides derived from propressophysin and prooxyphysin. This protein ('X') was not bound by a Concanavalin-A-Sepharose affinity column, although it had chromatographic properties similar to propressophysin on Sephadex G-75.
 ...
PMID:Biosynthesis of vasopressin, oxytocin, and neurophysins: isolation and characterization of two common precursors (propressophysin and prooxyphysin). 742 96

Methodology is described for characterization of the kinetics and equilibria of thiol/disulfide interchange reactions of the disulfide bonds in the neurohypophyseal peptide hormones arginine vasopressin and oxytocin and the related peptides pressinoic acid and tocinoic acid. Thiol/disulfide interchange reaction mixtures are analyzed by reversed-phase high-performance liquid chromatography. The effect of mobile-phase composition and pH on the HPLC capacity factors for the native disulfide and reduced dithiol forms of each peptide was examined. In each case, the capacity factor decreases as the acetonitrile content of the mobile phase increases. For each disulfide/dithiol peptide pair, the capacity factor is larger for the dithiol form of the peptide, indicating that the hydrophobic side chains of the linear peptide are more accessible for interaction with the hydrophobic stationary phase. To illustrate application of the methodology, rate and equilibrium constants are reported for the thiol/disulfide interchange reactions of cysteine with arginine vasopressin at pH 7.0. Cysteine reacts with arginine vasopressin to form two mixed disulfides, which in turn react with another molecule of cysteine to give the dithiol form of arginine vasopressin and cystine. Rate and equilibrium constants were determined for each step by analysis of reaction mixtures by HPLC. The results are compared to rate and equilibrium constants for reaction of cysteine with oxidized glutathione.
 ...
PMID:Characterization of the thiol/disulfide chemistry of neurohypophyseal peptide hormones by high-performance liquid chromatography. 825 69