Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P02794 (ferritin)
 17,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The bovine exocrine pancreatic cell produces a variety of enzymes and proenzymes for export. Biochemical studies by Greene L.J., C.H. Hirs, and G.E. Palade (J. Biol. Chem. 1963. 238:2054) have shown that the mass proportions of several of these proteins in resting pancreatic juice and zymogen granule fractions are identical. In this study we have used immunocytochemical techniques at the electron microscope level to determine whether regional differences exist in the bovine gland with regard to production of individual secretory proteins and whether specialization of product handling occurs at the subcellular level. The technique used is a modification of one previously reported (McLean, J.D., and S.J. Singer. 1970. Proc. Natl. Acad. Sci U.S.A. 69:1771) in which immunocytochemical reagents are applied to thin sections of bovine serum albumin-imbedded tissue and zymogen granule fractions. A double antibody technique was used in which the first step consisted of rabbit F(ab')2 antibovine secretory protein and the detection step consisted of sheep (F(ab')2 antirabbit F(ab')2 conjugated to ferritin. The results showed that all exocrine cells in the gland, and all zymogen granules and Golgi cisternae in each cell, were qualitatively alike with regard to their content of secretory proteins examined (trypsinogen, chymotrypsinogen A, carboxypeptidase A, RNase, and DNase). The data suggest that these secretory proteins are transported through the cisternae of the Golgi complex where they are intermixed before copackaging in zymogen granules; passage through the Golgi complex is apparently obligatory for these (and likely all) secretory proteins, and is independent of extent of glycosylation, e.g., trypsinogen, a nonglycoprotein vs. DNase, a glycoprotein.
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PMID:Immunocytochemical localization of secretory proteins in bovine pancreatic exocrine cells. 31

After exposure to ligand at 0-4 degrees C, estrogen receptors from mouse uteri characteristically eluted between thyroglobulin (Mr 669,000) and ferritin (Mr 443,000) during size-exclusion HPLC. However, when preparations were warmed with ligand under mild activating conditions, most or all of the receptor was observed as a much larger complex, which eluted between dextran blue 2000 and thyroglobulin. Formation of the large complex required ligand, was inhibited by molybdate, and occurred even in 0.4 M KCl. Slower ligand dissociation characterized the large complex, indicating that activated receptors were included preferentially. This large complex did not form when charged cytosols were aged, concentrated, or precipitated, indicating that formation was not the result of random aggregation. After exposure to conditions commonly used for activation (25 degrees C, 60 min), most receptor existed as a very large, monodisperse complex of finite size, predicting an ordered structure for these large complexes that should be useful for defining the types of proteins which can interact with estrogen receptors. Formation of the large complex was not impeded or disrupted by EDTA, RNase, DNase I, thiourea, or mercaptoethanol; however, the capacity to form this large complex was not demonstrated by preparations that had been exposed to trypsin or by the small receptor forms obtained after salt extraction. Proteolytic sensitivity and lack of sensitivity to RNase or DNase indicate that interactions between receptors and other proteins are involved in peak A formation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Intermolecular engagement of estrogen receptors indicated by the formation of a high molecular weight complex during activation. 251 8

Antigens A and B, shown to be associated with the progestagen-dominated human endometrium, were partly purified and their properties studied. The antigens were recovered in the crude nuclei, the heavy particulate fraction and cytosol of decidua-rich tissue from early pregnancy. The antigens in cytosol were enriched by a combination of Concanavalin A-Sepharose chromatography and polyacrylamide gel electrophoresis. The immunological reactivity of the antigens after partial purification by Concanavalin A-Sepharose chromatography was retained after 30 min exposure to 4-85 degrees C at pH 7.4, or after 2 h to pH 2-12 at 22 degrees C. Trypsin, but not pepsin, RNase, DNase or neuraminidase, completely destroyed immunological reactivity of both antigens. The apparent molecular weight of both antigens determined by filtration on Sephadex G100 was 48 000. The isoelectric point of both antigens was approximately 4.9. The antigens were not immunologically related to transferrin, ceruloplasmin, alpha-1-antitrypsin, ferritin, uteroglobin, alpha-fetoprotein, human chorionic gonadotrophin, pregnancy-associated plasma proteins or pregnancy zone protein. Furthermore, the antisera to Antigens A and B did not react with the decidual cytosol of pregnant baboons or of pseudopregnant rats.
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PMID:Properties of the progestagen-dependent protein of the human endometrium. 743 Dec 86

Although the role of iron in marine productivity has received a great deal of attention, no iron storage protein has been isolated from a marine microorganism previously. We describe an Fe-binding protein belonging to the Dps family (DNA binding protein from starved cells) in the N(2)-fixing marine cyanobacterium Trichodesmium erythraeum. A dps gene encoding a protein with significant levels of identity to members of the Dps family was identified in the genome of T. erythraeum. This gene codes for a putative Dps(T. erythraeurm) protein (Dps(tery)) with 69% primary amino acid sequence similarity to Synechococcus DpsA. We expressed and purified Dps(tery), and we found that Dps(tery), like other Dps proteins, is able to bind Fe and DNA and protect DNA from degradation by DNase. We also found that Dps(tery) binds phosphate, like other ferritin family proteins. Fe K near-edge X-ray absorption of Dps(tery) indicated that it has an iron core that resembles that of horse spleen ferritin.
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PMID:Overexpression and characterization of an iron storage and DNA-binding Dps protein from Trichodesmium erythraeum. 1659 98