Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:4.1.99.3 (PRE)
 1,923 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Avidin is a host acute defense protein induced by progestins and by inflammation caused by injurious factors such as microbes, viruses, toxic factors or tissue trauma. In the reproductive tract of egg-laying vertebrates avidin has evolved into a progestin-dependent secretory protein involved in anti-microbial action through its biotin avidity. For "progestin-dependent avidin" production, cellular differentiation by estrogen is necessary. In contrast, the expression of "progestin-independent or inflammation-induced avidin" does not require differentiation. Many cell types such as macrophages, heterophils and fibroblasts can produce avidin after non-specific cellular injuries. The wide distribution of avidin in avian, reptilian and amphibian species could be explained on the basis of its vital functions such as antimicrobial or antifungal, metabolic and immunomodulatory actions. The ontogeny of the progestin-dependent avidin synthesis is a complex event involving oviductal differentiation by steroid hormones leading to a specific gene expression. The first phase in oviductal differentiation by estrogens is characterized by a new chromatin organization and by an infiltration of progesterone receptor (PR)-containing mesenchymal cells into the subepithelial mucosa leading to epithelial cell differentiation ("mesenchymal and epithelial cell interaction"). The second phase in the differentiation of progestin-induced response is dependent on the presence of PR in the secretory cells. Two kinds of PR expression occur in the oviduct. The first is a "constitutive PR" and is found in the epithelial, submucosal and peritoneal cells of the immature chick oviduct without steroid treatment, and the second is an "inducible PR" found especially in the mucosal mesenchymal and smooth muscle cells. Avidin production requires PR in the target cells, but not all PR-containing cells can produce avidin. Therefore, in addition to PR, other transcription factors are needed to define the target cell specificity of the response to progestins. Earlier biochemical studies suggested that cytosolic and/or nuclear unoccupied PR was complexed as an 8 S form with the heat shock protein 90 (hsp90). Our immunohistochemical results, however, indicate that PR in vivo is not bound to hsp90, which is located entirely in the cytoplasm, whereas PR is an entirely nuclear protein in both ligand-occupied and unoccupied forms. Therefore, we assume that PR is a monomeric (4S) or homodimeric (5S) (chromatin?) protein associated to DNA. Ligand binding to PR appears to lead to a conformational change, dimer formation, tighter binding to PRE (progesterone responsive element) and to transcription factors, phosphorylation and proteolysis of PR as well as a chromatin change.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Development of progestin-specific response in the chicken oviduct. 248 92

Immunity to Plasmodium falciparum is contributed by many known and unknown factors. Lack of effective vaccine and rise in drug-resistant Plasmodium parasites leads to the major challenge in controlling the parasite. Determination of surface or secreted proteins which are essential for the survival of the pathogen is a very important step in finding potential vaccine candidates. Despite the discovery of several vaccine candidates against Plasmodium over the last decades, an effective vaccine is not available. The present study hypothesized that the PRE-binding protein (PREBP) could be a potential vaccine candidate against malaria pathogenesis. PREBP is highly conserved among the class Aconoidasida and exhibit high antigenicity and accessibility as a secretory protein. The present hypothesis was tested by employing in-silico translational genomics wherein the antigenicity, localization and the conservancy were determined.
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PMID:PRE-binding protein of Plasmodium falciparum is a potential candidate for vaccine design and development: An in silico evaluation of the hypothesis. 3090 38