Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.21.64 (proteinase K)
 4,071 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Normal and abnormal biopsies of the uterine cervix, to a total of 124 samples, have been analysed for the detection of oestrogen receptor (ER) mRNA. The tough fibrous nature of the cervix proved very resistant to disaggregation in the first instance and subsequently, it was difficult to extract good high molecular weight message. This necessitated a systematic study of methodological technique, including two methods of tissue disaggregation and five techniques of extraction of ER mRNA, which in total involved the use of 124 cervical biopsies. The most successful method involved chopping the tissue, then digesting the cells with proteinase K and extracting the nucleic acids in salt and sodium dodecyl sulphate. Using the perfected technique, 16 cervical biopsies obtained at serial intervals from four women did not show any differences in ER mRNA in cervical biopsies either in the presence of oral contraception or histological abnormality. The successful method described will prove valuable for the detection of ER message in human tumours and other tissues of similar nature.
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PMID:Oestrogen receptor message in premalignant and normal cervical cells: a methodological study. 842 90

The preovulatory surge of estrogen up-regulates estrogen receptor-alpha (ER) gene expression in the uterus during the estrous/menstrual cycles of female mammals. Previously, we demonstrated that the 5-fold increase in ER mRNA levels in endometrium of ovariectomized ewes treated with a physiological dose of estradiol (E2) is entirely due to an increase in ER mRNA stability. Our current work confirms that the E2 effect is specific to ER mRNA. The sequence of ER mRNA, cloned from sheep endometrium, shows a high degree of conservation with those of other species, even in the 5'- and the very long 3'-untranslated regions. In a cell-free assay, ER mRNA demonstrates greater stability with endometrial extracts from E2-treated ewes compared with those from untreated ovariectomized ewes. The E2-enhanced stability of ER mRNA was ablated by prior treatment of the extracts with proteinase K, 70 C heat, and oxidizing and alkylating reagents, indicating that a protein is responsible for stabilization of the message. The 3'-untranslated region of ER mRNA contains discrete sequences required for E2-enhanced stability, four of which were identified by extensive deletion mutant analyses. Transfer of two of the four minimal E2-modulated stability sequences conferred E2-enhanced stability to a heterologous RNA. These minimal E2-modulated stability sequences contain a common 10-base, uridine-rich sequence that is predicted to reside in a loop structure. Throughout our studies, estrogen stabilization of ER mRNA in sheep endometrium resembled that of vitellogenin mRNA in frog liver, indicating conservation of this ancient mechanism for enhancing gene expression in response to estrogen.
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PMID:Estradiol stabilizes estrogen receptor messenger ribonucleic acid in sheep endometrium via discrete sequence elements in its 3'-untranslated region. 1255 62