Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oestradiol treatment enhances type-II gonadotrophin (GTH-II) synthesis in the European eel (Anguilla anguilla) at the silver stage. As a first step in studying the molecular mechanisms involved in this stimulation, we cloned and characterized the cDNA encoding the beta subunit of eel GTH-II. A cDNA library was constituted in lambda gt10 from oestradiol-treated eels. It was screened using an oligodeoxyribonucleotide mixed probe designed to be complementary to a highly conserved region of cDNAs from several LH-related beta subunits. Several clones were obtained and four were subcloned in pUC13 and sequenced. The longest clones comprised a 420 bp coding sequence, plus 5' and 3' untranslated regions of 36 and 172 bp respectively. Comparison with GTH-II from other teleost fish permitted the localization of the putative cleavage site of a 24 amino acid signal peptide. The resulting 116 amino acid apopeptide had well-conserved cysteine positions and a putative N-linked glycosylation site; homology was 70-80% with GTH-II from other fish, 45% with LH from mammals and birds, 38% with mammalian FSH and only 35% with fish GTH-I. Preliminary results indicated a strong positive effect of oestradiol treatment on the level of the putative GTH-II beta-subunit mRNA. This supports our proposal that the European eel provides a suitable model for studying the positive regulation of gonadotrophin synthesis by gonadal steroids.
J Mol Endocrinol 1990 Jun
PMID:Molecular cloning and sequence analysis of the cDNA for the putative beta subunit of the type-II gonadotrophin from the European eel. 211 36

Human sex steroid-binding protein (hSBP) has been purified from late-pregnancy serum and labelled either by iodination (125I) or by photoaffinity with [3H]delta 6-testosterone. Using a micromanipulator, each labelled protein was separately injected into the lumen of epididymal tubules isolated from the head epididymis of the cynomologus monkey (Macaca fascicularis). Tubules were sampled from 3 to 90 min after the injection and processed for electron microscope autoradiography. Localization of the label occurred over the epididymal epithelium whichever tracer was used. The labelling was not randomly distributed over the different cell types constituting the epithelium, since only the 'principal cells' exhibited a silver grain count significantly greater than the background count. In these cells, labelled protein was found over endocytic organelles (coated structures, endosomes, multivesicular bodies and the trans Golgi network) and nuclei (including the nuclear envelope). Quantitative analysis demonstrated the same pattern of cellular and subcellular distribution for each tracer. Pretreatment with excess unlabelled protein significantly reduced the uptake of radioactivity by the principal cells, demonstrating the specificity of this phenomenon. This is the first study to show direct histological evidence for the internalization of hSBP in the primate epididymis, consistent with earlier immunohistochemical or biochemical localization of this protein. It is concluded that head epididymal cells are able to take up labelled hSBP across their apical membrane. The mechanism of internalization seems to involve endocytosis by the principal cells and leads to labelling of the nuclear compartment. This is strikingly similar to the pattern of uptake of rat androgen-binding protein (rABP) by rat epididymal cells previously demonstrated by our group. To what extent the chemical and structural homology between hSBP and rABP can be held responsible for the common cytophysiological behaviour of these sex steroid-binding proteins remains to be determined.
J Mol Endocrinol 1990 Dec
PMID:Internalization of human sex steroid-binding protein in the monkey epididymis. 212 29

1. In situ hybridization histochemistry was used to localize nerve growth factor receptor (NGFR) mRNA in the adult rat basal forebrain. 2. In emulsion-dipped sections 35S-labeled RNA antisense probes produced a high density of silver grains over cells located in the medial septum, vertical and horizontal limbs of the diagonal band of Broca, and nucleus basalis. 3. This distribution of NGFR mRNA overlaps with the distribution of NGFR protein localized using immunocytochemical techniques. 4. No hybridization signal was detected when sections were hybridized with a 35S-labeled RNA sense (control) probe. 5. We suggest that NGFRs are synthesized in these basal forebrain nuclei and transported to terminal areas where NGF is thought to be bound and internalized, an initial step in the many actions of this neurotrophic factor.
Cell Mol Neurobiol 1990 Mar
PMID:Localization of nerve growth factor receptor mRNA in the rat basal forebrain with in situ hybridization histochemistry. 215 82

In situ hybridization histochemistry and RNA blots were used to study expression of glutamic acid decarboxylase (GAD) mRNA in rat caudate-nucleus and substantia nigra. In situ hybridization combined with computerized image analysis revealed that in the intact substantia nigra reticulata the cross-section area of GAD mRNA positive neurons were 25% larger in the dorsolateral part as compared with the ventromedial part. A unilateral ibotenic acid injection in caudate-putamen lesioned neurons, some of which project to the ipsilateral substantia nigra. An increased level of GAD mRNA was observed in substantia nigra ipsilateral to the lesion. Computerized image analysis of sections from in situ hybridization revealed an increase in the number of silver grains over GAD mRNA positive neurons in the dorsolateral substantia nigra reticulata ipsilateral to the lesion. However, no change was observed in the ventromedial part suggesting that GAD mRNA expression in this part of the nigra is less sensitive to inhibition by caudate-putamen afferents. In agreement with in situ experiments, RNA blots showed a 2-fold increased level of GAD mRNA in substantia nigra ipsilateral to the lesion. The increased GAD mRNA expression in the deafferented substantia nigra suggests a disinhibition of nigral GABA neurons, resulting in an increased utilization of GABA in these substantia nigra neurons.
Brain Res Mol Brain Res 1990 Apr
PMID:Increased expression of glutamic acid decarboxylase mRNA in rat substantia nigra after an ibotenic acid lesion in the caudate-putamen. 215 80

In situ hybridization (ISH) was used to study at the electron microscope level, the subcellular localization of oxytocin (OT) mRNA in the rat hypothalamic magnocellular neurons. Rat brains were fixed with paraformaldehyde and glutaraldehyde and vibratome slices were incubated with a 25-base synthetic oligonucleotide complementary to OT mRNA and labelled at the 3'-end with [3H]dCTP. Hybridized slices were embedded in Epon after post-fixation with osmium tetroxide and cut into ultrathin sections that were processed for ultrastructural radioautography. OT mRNA was observed in magnocellular neurons of supra-optic and paraventricular nuclei in the vibratome sections. On ultrathin sections, the cytological preservation appeared to be satisfactory. Except for a few silver grains over the nucleus, sometimes close to its membrane, most grains were localized over the cytoplasm of some magnocellular neurons, where they frequently overlapped the endoplasmic reticulum. To decrease exposure time, ISH was also performed with OT probes labelled with a long tritiated tail. In this case, clusters of silver grains occurred over the cell nuclei not only in magnocellular neurons but also in non-secretory neurons and even in glial cells. However, an excess of poly C added to the hybridization buffer strongly decreased this non-cytoplasmic labelling. In conclusion, the results obtained with the short-tailed oligonucleotides demonstrate that these synthetic oligonucleotides have possible applications for the ultrastructural localization of mRNAs and constitute a powerful tool for the dynamic study of cellular mRNA processing in several physiological and experimental conditions.
Brain Res Mol Brain Res 1990 Jun
PMID:Ultrastructural localization of oxytocin mRNA in the rat hypothalamus by in situ hybridization using a synthetic oligonucleotide. 216 99

CUP2 is a copper-dependent transcriptional activator of the yeast CUP1 metallothionein gene. In the presence of Cu+ and Ag+) ions its DNA-binding domain is thought to fold as a cysteine-coordinated Cu cluster which recognizes the palindromic CUP1 upstream activation sequence (UASc). Using mobility shift, methylation interference, and DNase I and hydroxyl radical footprinting assays, we examined the interaction of wild-type and variant CUP2 proteins produced in Escherichia coli with the UASc. Our results suggest that CUP2 has a complex Cu-coordinated DNA-binding domain containing different parts that function as DNA-binding elements recognizing distinct sequence motifs embedded within the UASc. A single-amino-acid substitution of cysteine 11 with a tyrosine results in decreased Cu binding, apparent inactivation of one of the DNA-binding elements and a dramatic change in the recognition properties of CUP2. This variant protein interacts with only one part of the wild-type site and prefers to bind to a different half-site from the wild-type protein. Although the variant has about 10% of wild-type DNA-binding activity, it appears to be completely incapable of activating transcription.
Mol Cell Biol 1990 Sep
PMID:A single amino acid change in CUP2 alters its mode of DNA binding. 216 39

Calbindin-D28k (CaBP28k) protein and gene expression were examined in the mouse cerebellum during development and aging utilizing slot and Northern blot hybridization analyses for mRNA levels, Western blot analysis and radioimmunoassay (RIA) for protein levels, and by in situ studies using immunocytochemistry and hybridization cytochemistry on prepared tissue sections. Samples were obtained and analyzed from C57BL/6J mice aged day of birth and postnatal weeks 1, 2, 4, 8, and 120. A specific cDNA and antibody for CaBP28k were utilized in these studies. Analysis of mRNA levels showed a steady rise in CaBP28k mRNA from birth to a peak at postnatal week (3.4-fold increase) and then a decline to steady-state levels at postnatal weeks 4 and 8 (47% reduction of peak level) followed by a reduction of CaBP28k mRNA to birth levels at postnatal week 120. The specificity of the changes observed was tested by reprobing blots with beta-actin cDNA. Analysis of CaBP28k protein levels by both Western blot and RIA showed a similar pattern. In situ analysis of CaBP28k mRNA levels, based on hybridization signal (silver grains per cell), demonstrated a rise in cellular CaBP28k mRNA levels which peaked at postnatal week 2 (416.9 +/- 52.1) and then declined to steady-state levels by postnatal weeks 4 and 8 (267.4 +/- 35.8). Cellular CaBP28k mRNA levels exhibited a dramatic reduction in the aged cerebellum (postnatal week 120; 78.3 +/- 16.0). The levels of cellular CaBP28k mRNA corresponded to the intensity of immunoreactive CaBP28k localized by immunocytochemistry. The results are consistent with the hypothesis that CaBP28k may play a critical role in Purkinje cell maturation and maintenance.(ABSTRACT TRUNCATED AT 250 WORDS)
Brain Res Mol Brain Res 1990 Oct
PMID:Calcium binding protein (calbindin-D28k) gene expression in the developing and aging mouse cerebellum. 217 7

The NADPH:5 alpha-dihydroprogesterone 3 alpha-hydroxysteroid oxidoreductase (3 alpha-HSOR) [EC 1.1.1.50] which catalyzes the reversible conversion of 5 alpha-pregnane-3,20-dione (5 alpha-dihydroprogesterone; 5 alpha-DHP) to 3 alpha-hydroxy-5 alpha-pregnan- 20-one (3 alpha-,5 alpha-tetrahydroprogesterone; 3 alpha,5 alpha-THP) was purified to apparent homogeneity from female rat anterior pituitary cytosol by a three step micro-purification procedure. Specific activity of purified 3 alpha-HSOR was enriched 438-fold from that in pituitary cytosol using successive ion exchange, chromatofocusing and affinity column chromatography purification steps. 3 alpha-HSOR appears to be a monomer with an approximate molecular weight of 36 kDa and an isoelectric point of about 5.75. The purified enzyme appears as a single protein staining band (36 kDa) when examined by polyacrylamide gel electrophoresis and with both silver or Coomassie blue staining. Under non-dissociating electrophoretic conditions, all of the 3 alpha-HSOR activity co-migrated with the 36 kDa protein staining band. The purified enzyme in the presence of the preferred cofactor, NADPH, has an apparent Km for 5 alpha-DHP of 82 nM and a Vmax of 1.2 mumol of 3 alpha,5 alpha-THP formed per mg protein/30 min. The Km for NADPH was 0.71 microM. In the oxidative direction, the enzyme in the presence of NADP+ has a Km for 3 alpha,5 alpha-THP of 1.4 microM and a Vmax of 9.7 mumol of 5 alpha-DHP formed per mg protein/30 min. The Km for NADP+ was 1.6 microM.
J Steroid Biochem Mol Biol 1990 Oct
PMID:Purification of the NADPH:5 alpha-dihydroprogesterone 3 alpha-hydroxysteroid oxidoreductase from female rat pituitary cytosol. 226 52

p29, a 29 kDa protein recognised by D5, a monoclonal antibody prepared against partially purified cytosolic estrogen receptor (ER), has been purified to homogeneity from ZR-75-1, a human breast cancer cell line. Ammonium sulphate fractionation followed by immunoaffinity chromatography on a three column system using Protein A-Sepharose coupled D5, produced purified p29. Silver stained SDS one-dimensional polyacrylamide gel electrophoresis (PAGE) and two-dimensional PAGE showed p29 to have been purified to homogeneity. Amino acid analysis showed no unusual characteristics. Partial N-terminal sequencing studies showed that purified p29 shared a 100% homology with the sequence of a pp89, murine cytomegaloviral protein.
J Steroid Biochem Mol Biol 1990 Nov 30
PMID:Immunoaffinity purification and characterisation of p29--an estrogen receptor related protein. 227 35

To establish the progenitor role of bronchial epithelial cells in the steady state, we undertook a quantitative autoradiographic study in normal hamsters. Groups of 7 hamsters were killed 1 h and 1, 2, 3, 4, 7, and 14 d after an intraperitoneal injection of [3H]thymidine (2 microCi/g body wt). Autoradiograms were prepared from 861 Epon sections, 2 microns thick, of left intrapulmonary hilar bronchi. Epithelial cells were classified into 1 of 7 categories: basal-1 (B1) and basal-2 (B2), depending on nuclear height; secretory cells denoted as S1 with zero to 4 granules, S2 with 5 or more granules with intervening cytoplasm, and S3 with abundant granules completely filling the cytoplasm; ciliated (C); and indeterminate (IN). Mean silver grain counts decreased significantly over time only for B1 cells (P less than 0.05), with a cell cycle time of 20.6 d and a DNA synthetic time of 7.5 h. Labeled cells, 1 h after thymidine injection, comprised 30.5% S1, 27.8% B1, 22.8% B2, 6.8% IN, 6.4% S2, 5.7% C, and 0% S3 cells. Labeling indices of individual cell categories (LIc), at 1 h after labeling, were highest for B1 followed by B2 cells, reflecting their proliferative intensity. Labeling index of all epithelial cells combined did not change with time, indicating that there was no major cell death or label dilution. The LIc decreased significantly over time only for B1 and B2 cells (P less than 0.001 and P less than 0.002, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)
Am J Respir Cell Mol Biol 1990 Jan
PMID:Cell kinetics of normal adult hamster bronchial epithelium in the steady state. 230 69


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