Is mRNA sequestration involved in the regulation of progesterone 14α-hydroxylase cytochrome P-450 expression in Mucor hiemalis ?

• Published in: Microbiology (Society for General Microbiology) 1994, Vol.140 (7), p.1633-1640
• Main Authors: ANTONIOU, T. N. H, CURRAN, B. P. G, SMITH, K. E
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Biology of microorganisms of confirmed or potential industrial interest; Biotechnology; Fundamental and applied biological sciences. Psychology; Growth, nutrition, metabolism, transports, enzymes. Molecular biology; Microbiology; Mission oriented research; Mucor hiemalis; Mycology; Physiology and metabolism
• ISSN: 1350-0872; 1465-2080
• DOI: 10.1099/13500872-140-7-1633

During a 6 h incubation at 26 degree C, Mucor hiemalis hydroxylated progesterone predominantly at the 14 alpha site. Further incubation resulted in the production of several 14 alpha -dihydroxyprogesterones and a novel microbial transformation product, 8(9), 14(15)-didehydroprogesterone (pregna-4,8[9], 14[15]-triene-3,20-dione). Azole inhibition indicates that the hydroxylases are cytochromes P-450. Mycelia transformed in the presence of the translation inhibitor cycloheximide failed to hydroxylate progesterone, whereas identical treatment with the transcription inhibitor actinomycin D, or heat-shock for 1 h at 37 degree C prior to progesterone transformation, stimulated hydroxylation. 14 alpha -Hydroxylation was stimulated if mycelia were pre-incubated with progesterone, transcription or translation inhibitors. These data are consistent with a model in which cytochrome P-450 steroid hydroxylase mRNA is stored in cells in a dormant form by a labile sequestering protein.