Donald W. Back

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The rates of synthesis of fatty acid synthase and the levels of its mRNA are high in livers of chicks, ducklings, or goslings fed high-carbohydrate mash diets and low in livers of starved birds, indicating pretranslational regulation of fatty acid synthase activity. Determination of the step(s) at which the nutritional state regulates the fatty acid(More)
Choristoneura fumiferana multicapsid nucleopolyhedrovirus (CfMNPV) is a baculovirus pathogenic to spruce budworm, the most damaging insect pest in Canadian forestry. CfMNPV is less virulent to its host insect and its replication cycle is slower than the baculovirus type species Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) but the basis(More)
Mechanisms involved in stimulation of the synthesis of malic enzyme by insulin and triiodothyronine and in inhibition of synthesis by glucagon have been investigated by assessing levels and rates of synthesis of malic enzyme mRNA in chick embryo hepatocytes in culture. Insulin alone had no effect on the level of malic enzyme mRNA, whereas triiodothyronine(More)
Mechanisms involved in the multihormonal regulation of fatty acid synthase have been investigated by comparing levels of its mRNA with rates of enzyme synthesis in chick embryo hepatocytes in culture. Triiodothyronine or insulin caused about a 2.5-fold increase in the relative rate of synthesis of fatty acid synthase. Together, these hormones were(More)
The levels of malic enzyme and fatty acid synthase are increased by feeding and decreased by starvation in liver in vivo and are increased by triiodothyronine and decreased by glucagon in hepatocytes in culture. Cloned malic enzyme and fatty acid synthase cDNAs are being used to analyze regulation of these unique genes. Dietary regulation of both enzymes(More)
The mRNAs for fatty acid synthase and malic enzyme were almost undetectable in total RNA extracted from the livers of 16-day old chick embryos. Both mRNAs increased in abundance between the 16th day of incubation and the day of hatching. In neonates, fatty acid synthase mRNA level was dependent on nutritional status, increasing slowly if the chicks were(More)
The amount of malic enzyme mRNA in total liver RNA increased rapidly when starved ducklings were fed a high-carbohydrate mash diet, reaching 15 times the initial level at 9 h and an apparent steady state, about 20 times the initial level, at 24 h. Based on the kinetics of accumulation, malic enzyme mRNA had a half-life of 3-5 h in the livers of fed(More)
A series of compounds that increase the activity of delta-aminolevulinic acid synthase (ALAS) in chick embryo hepatocyte cultures were studied for their effects on steady-state levels of mRNA for ALAS and phenobarbital-inducible cytochrome PB1 P450. N-Ethylprotoporphyrin IX (N-EtPP), which is believed to lower heme levels by inhibition of ferrochelatase(More)
A full-length cDNA for the human liver mitochondrial cytochrome P-450 CYP27 was cloned from a human hepatoma HepG2 cDNA library and then subcloned into the mammalian expression vector pSG5. When CYP27 cDNA was transfected into COS-1 transformed monkey kidney cells along with adrenodoxin cDNA, transfected cells revealed a 10- to 20-fold higher vitamin(More)
Sensitive immunochemical assays were used to measure the mass and rate of synthesis of malic enzyme protein in wild-type and Mod-1n mutant mice fed a high carbohydrate/low fat diet supplemented with thyroid hormone. Malic enzyme activity in the fed, wild-type mice was 100-fold higher than in starved, wild-type mice. Neither activity, mass, nor synthesis of(More)