Matches in SemOpenAlex for { <https://semopenalex.org/work/W2079603189> ?p ?o ?g. }
- W2079603189 endingPage "23" @default.
- W2079603189 startingPage "13" @default.
- W2079603189 abstract "The first step in the biosynthesis of ecdysteroids by Manduca sexta prothoracic glands, the conversion of cholesterol to 7-dehydrocholesterol, is mediated by an enzyme with characteristics of a microsomal cytochrome P-450, i.e. sensitivity to CO and fenarimol, and a requirement for NADPH. The enzyme responsible for hydroxylation at C-25 of the putative 3-dehydroecdysone precursor, 14-hydroxy-5β-cholest-7-en-3,6-dione, is also microsomal, while those mediating hydroxylations at C-22 and C-2 of 3,14,25-trihydroxy-5β-cholest-7-en-6-one are mitochondrial. Indirect evidence revealed that the steps between 7-dehydrocholesterol and the trideoxyecdysteroids occur in the mitochondria, suggesting that extensive shuttling of intermediates between the endoplasmic reticulum and mitochondria takes place in the prothoracic gland cell during ecdysteroid biosynthesis. During the fifth larval instar, cholesterol 7,8-dehydrogenase activity is evident from days 2 to 9, while the conversion to [3H]ecdysteroids is not significant prior to the ecdysteroid commitment peak on day 4. Terminal hydroxylase activity shows little change throughout the instar. These data support the hypothesis that regulation of the biosynthetic pathway by PTTH occurs at the step immediately following the formation of 7-dehydro-cholesterol. The steroid biosynthesis inhibitor, fenarimol, has been shown to inhibit each of these P-450 enzymes, as well as fat body ecdysone 20-monooxygenase, with an I50 of 10−4 M in disrupted glands, suggesting that it is a general P-450 inhibitor. The secretion of ecdysteroids by the glands in vitro is very sensitive to fenarimol, i.e. I50 of 10−6 M. RH5849, 1,2- dibenzoyl-1-tert-butylhydrazine, fails to inhibit any of these prothoracic gland reactions, yet strongly inhibits fat body ecdysone 20-monooxygenase activity. This suggests that RH5849 is a specific ecdysteroid substrate/product mimic in this reaction." @default.
- W2079603189 created "2016-06-24" @default.
- W2079603189 creator A5057813286 @default.
- W2079603189 creator A5065780513 @default.
- W2079603189 creator A5069286112 @default.
- W2079603189 date "1993-01-01" @default.
- W2079603189 modified "2023-09-27" @default.
- W2079603189 title "Early steps in ecdysteroid biosynthesis: Evidence for the involvement of cytochrome P-450 enzymes" @default.
- W2079603189 cites W1488907063 @default.
- W2079603189 cites W1580411717 @default.
- W2079603189 cites W1961534644 @default.
- W2079603189 cites W1967744233 @default.
- W2079603189 cites W1974584213 @default.
- W2079603189 cites W1980203712 @default.
- W2079603189 cites W1989831398 @default.
- W2079603189 cites W1991464513 @default.
- W2079603189 cites W2003883951 @default.
- W2079603189 cites W2004145896 @default.
- W2079603189 cites W2008441362 @default.
- W2079603189 cites W2017529156 @default.
- W2079603189 cites W2019465820 @default.
- W2079603189 cites W2020570437 @default.
- W2079603189 cites W2024186036 @default.
- W2079603189 cites W2030571034 @default.
- W2079603189 cites W2032301582 @default.
- W2079603189 cites W2033002048 @default.
- W2079603189 cites W2042122219 @default.
- W2079603189 cites W2052436308 @default.
- W2079603189 cites W2052828899 @default.
- W2079603189 cites W2053045295 @default.
- W2079603189 cites W2055350011 @default.
- W2079603189 cites W2055503134 @default.
- W2079603189 cites W2055635074 @default.
- W2079603189 cites W2055784350 @default.
- W2079603189 cites W2062623525 @default.
- W2079603189 cites W2067492092 @default.
- W2079603189 cites W2079434976 @default.
- W2079603189 cites W2080717570 @default.
- W2079603189 cites W2083862962 @default.
- W2079603189 cites W2083954894 @default.
- W2079603189 cites W2085669101 @default.
- W2079603189 cites W2088812261 @default.
- W2079603189 cites W2145650849 @default.
- W2079603189 cites W2148859347 @default.
- W2079603189 cites W2331340467 @default.
- W2079603189 cites W2333988945 @default.
- W2079603189 cites W2338649185 @default.
- W2079603189 cites W2340800860 @default.
- W2079603189 cites W2801172849 @default.
- W2079603189 cites W44114224 @default.
- W2079603189 cites W82297159 @default.
- W2079603189 doi "https://doi.org/10.1016/0965-1748(93)90077-6" @default.
- W2079603189 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/8485514" @default.
- W2079603189 hasPublicationYear "1993" @default.
- W2079603189 type Work @default.
- W2079603189 sameAs 2079603189 @default.
- W2079603189 citedByCount "94" @default.
- W2079603189 countsByYear W20796031892012 @default.
- W2079603189 countsByYear W20796031892013 @default.
- W2079603189 countsByYear W20796031892014 @default.
- W2079603189 countsByYear W20796031892015 @default.
- W2079603189 countsByYear W20796031892017 @default.
- W2079603189 countsByYear W20796031892018 @default.
- W2079603189 countsByYear W20796031892019 @default.
- W2079603189 countsByYear W20796031892020 @default.
- W2079603189 countsByYear W20796031892021 @default.
- W2079603189 countsByYear W20796031892022 @default.
- W2079603189 countsByYear W20796031892023 @default.
- W2079603189 crossrefType "journal-article" @default.
- W2079603189 hasAuthorship W2079603189A5057813286 @default.
- W2079603189 hasAuthorship W2079603189A5065780513 @default.
- W2079603189 hasAuthorship W2079603189A5069286112 @default.
- W2079603189 hasConcept C126322002 @default.
- W2079603189 hasConcept C127078168 @default.
- W2079603189 hasConcept C13002179 @default.
- W2079603189 hasConcept C134018914 @default.
- W2079603189 hasConcept C170493617 @default.
- W2079603189 hasConcept C173758957 @default.
- W2079603189 hasConcept C181199279 @default.
- W2079603189 hasConcept C2776071262 @default.
- W2079603189 hasConcept C2776905768 @default.
- W2079603189 hasConcept C2777180181 @default.
- W2079603189 hasConcept C2780312687 @default.
- W2079603189 hasConcept C2780768313 @default.
- W2079603189 hasConcept C47002013 @default.
- W2079603189 hasConcept C526171541 @default.
- W2079603189 hasConcept C553450214 @default.
- W2079603189 hasConcept C55493867 @default.
- W2079603189 hasConcept C59822182 @default.
- W2079603189 hasConcept C71315377 @default.
- W2079603189 hasConcept C71924100 @default.
- W2079603189 hasConcept C86803240 @default.
- W2079603189 hasConcept C87644729 @default.
- W2079603189 hasConceptScore W2079603189C126322002 @default.
- W2079603189 hasConceptScore W2079603189C127078168 @default.
- W2079603189 hasConceptScore W2079603189C13002179 @default.
- W2079603189 hasConceptScore W2079603189C134018914 @default.
- W2079603189 hasConceptScore W2079603189C170493617 @default.