Isoprenoid synthesis in isolated embryonic Drosophila cells. Sterol-independent regulatory signal molecule is distal to isopentenyl 1-pyrophosphates - PubMed (original) (raw)

Comparative Study

. 1985 Nov 15;260(26):14083-91.

Free article

Comparative Study

Isoprenoid synthesis in isolated embryonic Drosophila cells. Sterol-independent regulatory signal molecule is distal to isopentenyl 1-pyrophosphates

J A Watson et al. J Biol Chem. 1985.

Free article

Abstract

Embryonic Drosophila cells (Kc cells) were used to further characterize sterol-independent modulation of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity. 3-Methyl-3-5-dihydroxyvalerate (mevalonate), 3-fluoromethyl-3,5-dihydroxyvalerate (fluoromevalonate), and 3-ethyl-3,5-dihydroxyvalerate (homomevalonate) were tested as modulators. Although mevalonate caused a rapid, reversible suppression of reductase activity, fluoro- and homomevalonate increased activity; fluoromevalonate was more effective than homomevalonate. Mevalonate, added simultaneously with fluoromevalonate, blocked the analogue's effect on Kc cell reductase activity. However, mevalonate did not suppress an established fluoromevalonate increase in HMG-CoA reductase activity. Fluoromevalonate blocked [1-14C, 5-3H]mevalonate conversion to 14CO2- and 3H-labeled lipids and [3H] mevalonate 5-pyrophosphate accumulated. Neither protein nor RNA synthesis were required for mevalonate-mediated suppression of reductase activity. However, fluoromevalonate's effect on reductase activity required protein synthesis. Furthermore, in the absence of protein synthesis, fluoromevalonate-stabilized Kc cell HMG-CoA reductase activity. We have concluded that mevalonate, fluoromevalonate, homomevalonate, and compactin (mevinolin) modulated HMG-CoA reductase activity because they altered isoprenoid carbon flow to a post-isopentenyl 1-pyrophosphate regulatory, signal molecule.

PubMed Disclaimer

Similar articles

Cited by

Publication types

MeSH terms

Substances

LinkOut - more resources