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F Fridlansky

Publications and source records attributed to F Fridlansky.

15 recordsLinked to original sources
PubMed1989

Preliminary assignments of the aromatic and some methyl group resonances of the 1H-NMR spectrum of the oxidized form of uteroglobin. Application to the interaction of oxidized uteroglobin with progesterone.

Two-dimensional NMR methods have been used to assign aromatic and methyl group resonances in the 1H-NMR spectrum of oxidized uteroglobin. Assignments to specific amino acids are based on X-ray-determined structures of two crystal forms (C222(1) and P2(1] and on an energy-minimized X-ray structure of the C222(1) form of uteroglobin. These preliminary assignments are sufficient to probe the interaction of oxidized uteroglobin with progesterone in solution. The protein global structure is unmodified but some direct or indirect conformational changes are induced in the H1H4(H1'H4') pockets and close to Phe28 by progesterone.

Binding Sites↗
PubMed1987

Refinement of the C222(1) crystal form of oxidized uteroglobin at 1.34 A resolution.

The structure of uteroglobin, a progesterone binding protein from rabbit uterine fluid, was determined and refined at 1.34 A resolution to a conventional R-factor of 0.229. The accuracy of the co-ordinates is estimated to be 0.15 A. The isotropic temperature factor of individual atoms was refined and its average value is 11.9 A2 for the 548 non-hydrogen atoms of the protein monomer. A total of 83 water molecules was located in difference electron density maps and refined, first using a constant occupancy factor of 1 and then variable occupancy, the final (Q) being 0.63. The mean temperature factor of the water oxygen atoms is 26.4 A2. Uteroglobin is a dimer and its secondary structure consists of four alpha-helices per monomer that align in an anti-parallel fashion. There is one beta-turn between helix 2 and helix 3 (Lys26 to Glu29); 76% of the residues are part of the alpha-helices. In the core of the dimeric protein molecule, between the two monomers that are held together by two disulfide bridges, we have observed a closed cavity. Its length is 15.6 A and its width is 9 A; 14 water molecules could be positioned inside. In the "bottom" part of the protein, near the C terminus, we have observed a smaller cavity, occupied by two water molecules. The calculation of the molecular surface revealed four surface pockets whose possible functional implications are discussed below.

Amino Acid Sequence↗
PubMed1987

Complete amino acid sequence of the human progesterone receptor deduced from cloned cDNA.

A lambda gt10 library containing DNAs complementary to messenger RNAs from human breast cancer T47-D cells was constructed and screened with a cDNA probe encoding the rabbit progesterone receptor. Four overlapping clones have been sequenced. The open reading frame corresponds to a protein of 933 amino acids with a molecular weight of 98,868 Da. The cysteine rich basic region supposed to be involved in DNA binding is completely homologous in the human and rabbit receptors, whereas the C-terminal end, where hormone binding is thought to take place, differs by a single amino acid change. The human progesterone receptor is characterized, as is the rabbit receptor, by the very high proline content of its N-terminal region. When mRNAs from either human breast cancer cell lines T47-D and MCF-7 or from normal human uterus tissue were blotted and probed with the cloned cDNA, four main bands were observed (5100, 4300, 3700, and 2900 nucleotides).

Amino Acid Sequence↗
PubMed1987

Submicroscopic duplication of chromosome 21 and trisomy 21 phenotype (Down syndrome).

A patient with the phenotype of trisomy 21 (Down syndrome) was found to have a normal karyotype in blood lymphocytes and fibroblasts. Assessment of the chromosome 21 markers SOD1, CBS, ETS2, D21S11, and BCEI showed partial trisomy by duplication of a chromosome segment carrying the SOD1, CBS, and ETS2 loci and flanked by the BCEI and D21S11 loci, which are not duplicated. This submicroscopic duplication at the interface of 21q21 and 21q22.1 reduces to about 2000-3000 kb the critical segment the trisomy of which is responsible for the phenotype of trisomy 21.

Adult↗
PubMed1985

Cloning of a gene expressed in human breast cancer and regulated by estrogen in MCF-7 cells.

Messenger RNAs (mRNAs) were prepared from MCF-7 breast cancer cells grown in the presence of estradiol. Complementary DNAs (cDNAs) were inserted into pBR322 plasmid and a library of 4400 recombinant bacterial clones was prepared. The clones were screened by in situ differential hybridization with cDNAs prepared from RNAs of MCF-7 cells grown either in the presence or absence of estradiol. Several estrogen-induced or estrogen-repressed clones were identified. One of them corresponded to a relatively frequent mRNA (0.8% of recombinant plasmids) of 650 nucleotides. The concentration of this mRNA was increased by estradiol (half maximal induction approximately 0.05 nM) but not by progesterone, dexamethasone, or dihydrotestosterone. Tamoxifen inhibited the effect of estradiol but was devoid of any agonistic activity when administered separately. This messenger was present in biopsies of breast cancer, but not in endometrium or liver. The cloned cDNA was sequenced. An open reading frame was found corresponding to a protein of less than 100 amino acids. A search of data banks showed no identity or marked similarity to previously published DNA or protein sequences, particularly to those of growth factors evoked by some characteristics of the coded polypeptide. The cloned cDNA probe was used to screen a library of Charon 4A phage containing human genomic fragments. Screening of 300,000 phages yielded two different recombinants hybridizing to the cDNA. Southern blot experiments using DNA from recombinant phage, MCF-7 cells, and placenta showed the presence of a unique gene exhibiting a similar restriction pattern in DNAs from malignant and nonmalignant tissues.

Amino Acid Sequence↗
PubMed1980

[Uteroglobin].

Uteroglobin has been studied under two aspects: 1) as a model of specific interaction between a protein and a steroid hormone: crystals were obtained and analyzed by X-ray diffraction; 2) as a marker of progesterone action in the endometrium: messenger RNA was translated, purified and transcribed into complementary DNA.

Animals↗
PubMed1979

N-terminal sequences of uteroglobin and its precursor.

Translation of uteroglobin mRNA in wheat-germ extract has yielded a precursor protein (pre-uteroglobin) containing an N-terminal extension of 21 amino acid residues. The sequence of this extension and that of the 50 N-terminal amino acid residues of uteroglobin have been determined.

Amino Acid Sequence↗
PubMed1976

Interaction of uteroglobin with progesterone, 5alphapregnane-3,20-dione and estrogens.

Uteroglobin was obtained from 5 day pregnant rabbits and purified to homogeneity by Sephadex G 75 and DEAE-cellulose chromatographies. Progesterone binding to uteroglobin was decreased by lyophilization and enhanced by SH-reducing agents. Dithiothreitol was more effective than dithioerythritol, and beta-mercaptoethanol was only active at 25 to 100 mM concentrations. SH-blocking agents (iodoacetate, iodoacetamide, phydroxymercuribenzoate and, dithiobisnitrobenzoic acid) inhibited binding. In the absence of SH-reducing agents only one in every 500 uteroglobin molecules bound the hormone, whereas under optimal conditions (20 mM dithiothreitol) one in every two molecules bound progesterone. There was no significant difference in equilibrium dissociation constants under these two conditions. Uteroglobin had a relatively high affinity for progesterone (KD=4.1 X 10(-7)M) but a threefold higher affinity for 5alpha-pregnane-3,20-dione (KD=1.3 X 10(-7)M). Estradiol was bound but non-specifically with a very low affinity, and its binding was not enhanced by SH-reducing agents. Hormonal specificity of binding to uteroglobin was different from that of binding to rabbit uterine progesterone receptor. Various synthetic progestagens (chlormadinone acetate, norethisterone, R5020) were bound to the latter but not to the former protein. Diethylstilbestrol had some affinity (15% of that of progesterone) for uteroglobin and no affinity for the progesterone receptor. Uteroglobin incubated in the presence or absence of cofactors (NADH and NADPH) with or without dithiothreitol did not metabolize progesterone.

Androgens↗