Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
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Gene/Protein
Disease
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Drug
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Target Concepts:
Gene/Protein
Disease
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Drug
Enzyme
Compound
Query: EC:6.4.1.2 (
acetyl-CoA carboxylase
)
2,876
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Hepatocytes isolated from 9-week-old chickens were cultured in a serum-free, hormonally defined medium. Relative amounts of mRNAs coding for lipogenic enzymes (
acetyl-CoA carboxylase
, fatty acid synthase, delta 9 desaturase, malic enzyme) and apoproteins (
apoprotein
A1 and
apoprotein
B) were determined until the 12th day. beta-actin and albumin mRNA, as well as albumin secretion, were also assessed. Cellular metabolic activity appeared to be very low for the first days of culture, but increased after the 7th day. All the mRNAs studied, except for that of malic enzyme, were present from this time throughout the culture lifespan. The biological significance of the observed results and the relevance of this chicken hepatocyte culture system for long-term metabolic and genetic studies are discussed.
...
PMID:Lipogenic enzyme and apoprotein messenger RNAs in long-term primary culture of chicken hepatocytes. 810 Feb 36
The intracellular compartmentation of biotin holocarboxylase synthetase has been investigated in pea (Pisum sativum) leaves, by isolation of organelles and fractionation of protoplasts. Enzyme activity was mainly located in cytosol (approx. 90% of total cellular activity). Significant activity was also identified in the soluble phase of both mitochondria and chloroplasts. Two enzyme forms were separated by anion-exchange chromatography. The major form was found to be specific for the cytosol compartment, whereas the minor form was present in mitochondria as well as in chloroplasts. We also report the isolation and DNA sequence of a cDNA encoding an Arabidopsis thaliana biotin holocarboxylase synthetase. This cDNA was isolated by functional complementation of a conditional lethal Escherichia coli birA (biotin ligase gene, which regulates biotin synthesis) mutant. This indicated that the recombinant plant protein was able to biotinylate specifically an essential
apoprotein
substrate in the bacterial host, that is a subunit of
acetyl-CoA carboxylase
called biotin carboxyl carrier protein. The full-length nucleotide sequence (1534 bp) encodes a protein of 367 amino acid residues with a molecular mass of 41172 Da and shows specific regions of similarity to other biotin holocarboxylase synthetase genes as isolated from bacteria and yeast, and with cDNA species from human. A sequence downstream of the first translation initiation site encodes a putative peptide structurally similar to organelle-targeting pre-sequences, suggesting a mitochondrial or chloroplastic localization for this isoform.
...
PMID:Evidence for multiple forms of biotin holocarboxylase synthetase in pea (Pisum sativum) and in Arabidopsis thaliana: subcellular fractionation studies and isolation of a cDNA clone. 917 80
Avian lipogenesis was studied in the chicken hepatocarcinoma LMH cell line. The differentiated and lipogenic status of these cells was evidenced by the presence of the albumin mRNA as well as of some mRNA coding for enzymes involved in lipogenesis (
acetyl-CoA carboxylase
, fatty acid synthase, delta 9 desaturase) and for apoproteins (
apoprotein
B and A1). These results were further confirmed by the analysis of triglyceride synthesis and secretion rates in growing cells. A time course analysis showed that triglyceride metabolism was affected by cell density. Hormone responsiveness of triglyceride production was also analyzed. Insulin, triiodothyronine and glucagon to a lesser extent were shown to regulate lipogenesis of LMH cells. The results were compared with those obtained in primary cultures of chicken hepatocytes.
...
PMID:Triglyceride synthesis and secretion and lipogenesis implicated gene expression in the chicken hepatocarcinoma cell line LMH. 940 72
Fatty acid and lipoic acid biosynthesis were investigated in plant mitochondria. Although the mitochondria lack
acetyl-CoA carboxylase
, our experiments reveal that they contain the enzymatic equipment necessary to transform malonate into the two main building units for fatty acid synthesis: malonyl- and acetyl-acyl carrier protein (ACP). We demonstrated, by a new method based on a complementary use of high performance liquid chromatography and mass spectrometry, that the soluble mitochondrial fatty-acid synthase produces mainly three predominant acyl-ACPs as follows: octanoyl(C8)-, hexadecanoyl(C16)-, and octadecanoyl(C18)-ACP. Octanoate production is of primary interest since it has been postulated long ago to be a precursor of lipoic acid. By using a recombinant H
apoprotein
mutant as a potential acceptor for newly synthesized lipoic acid, we were able to detect limited amounts of lipoylated H protein in the presence of malonate, several sulfur donors, and cofactors. Finally, we present a scheme outlining the new biochemical pathway of fatty acid and lipoic acid synthesis in plant mitochondria.
...
PMID:Fatty acid and lipoic acid biosynthesis in higher plant mitochondria. 1067 42
The finding that expression of a cholesterol 7alpha-hydroxylase (CYP7A1) transgene in cultured rat hepatoma cells caused a coordinate increase in lipogenesis and secretion of apoB-containing lipoproteins led to the hypothesis that hepatic production of apoB-containing lipoproteins may be linked to the expression of CYP7A1 (Wang, S.-L., Du, E., Martin, T. D., and Davis, R. A. (1997) J. Biol. Chem. 272, 19351-19358). To examine this hypothesis in vivo, a transgene encoding CYP7A1 driven by the constitutive liver-specific enhancer of the human
apoE
gene was expressed in C56BL/6 mice. The expression of CYP7A1 mRNA (20-fold), protein ( approximately 10-fold), and enzyme activity (5-fold) was markedly increased in transgenic mice compared with non-transgenic littermates. The bile acid pool of CYP7A1 transgenic mice was doubled mainly due to increased hydrophobic dihydroxy bile acids. In CYP7A1 transgenic mice, livers contained approximately 3-fold more sterol response element-binding protein-2 mRNA. Hepatic expression of mRNAs encoding lipogenic enzymes (i.e. fatty-acid synthase,
acetyl-CoA carboxylase
, stearoyl-CoA desaturase, squalene synthase, farnesyl-pyrophosphate synthase, 3-hydroxy-3-methylglutaryl-CoA reductase, and low density lipoprotein receptor) as well as microsomal triglyceride transfer protein were elevated approximately 3-5-fold in transgenic mice. CYP7A1 transgenic mice also displayed a >2-fold increase in hepatic production and secretion of triglyceride-rich apoB-containing lipoproteins. Despite the increased hepatic secretion of apoB-containing lipoproteins in CYP7A1 mice, plasma levels of triglycerides and cholesterol were not significantly increased. These data suggest that the 5-fold increased expression of the low density lipoprotein receptor displayed by the livers of CYP7A1 transgenic mice was sufficient to compensate for the 2-fold increase production of apoB-containing lipoproteins. These findings emphasize the important homeostatic role that CYP7A1 plays in balancing the anabolic lipoprotein assembly/secretion pathway with the cholesterol catabolic bile acid synthetic pathway.
...
PMID:Increased production of apolipoprotein B-containing lipoproteins in the absence of hyperlipidemia in transgenic mice expressing cholesterol 7alpha-hydroxylase. 1132 27
An experiment was conducted to investigate the effect of niacin supplementation on hepatic lipid metabolism in rabbits. Rex Rabbits (90 d, n = 32) were allocated to two equal treatment groups: Fed basal diet (control) or fed basal diet with additional 200 mg/kg niacin supplementation (niacin). The results show that niacin significantly increased the levels of plasma adiponectin, hepatic
apoprotein
B and hepatic leptin receptors mRNA (p<0.05), but significantly decreased the hepatic fatty acid synthase activity and adiponectin receptor 2, insulin receptor and
acetyl-CoA carboxylase
mRNA levels (p<0.05). Plasma insulin had a decreasing tendency in the niacin treatment group compared with control (p = 0.067). Plasma very low density lipoproteins, leptin levels and the hepatic adiponectin receptor 1 and carnitine palmitoyl transferase 1 genes expression were not significantly altered with niacin addition to the diet (p>0.05). However, niacin treatment significantly inhibited the hepatocytes lipid accumulation compared with the control group (p<0.05). In conclusion, niacin treatment can decrease hepatic fatty acids synthesis, but does not alter fatty acids oxidation and triacylglycerol export. And this whole process attenuates lipid accumulation in liver. Besides, the hormones of insulin, leptin and adiponectin are associated with the regulation of niacin in hepatic lipid metabolism in rabbits.
...
PMID:Dietary Niacin Supplementation Suppressed Hepatic Lipid Accumulation in Rabbits. 2700 17
Due to their health-promoting effects green tea catechins have gained a keen interest in recent years in the context of bodyweight reduction treatments and alleviation of inflammatory diseases. This study was designed to evaluate the impact of native and thermally modified catechins (TMC) on the body weight gain, fatty acid profile in subcutaneous adipose tissue and the activity of the enzymes involved in lipid metabolism regulation: AMP-dependent protein kinase (AMPK) and
acetyl-CoA carboxylase
(
ACC
) in
apoE
-deficient mice maintained on a high-fat diet. We observed that TMC decreased bodyweight gain as compared to the control group. Furthermore, TMC increased AMPK activity and reduced
ACC
activity in the metabolically important tissues: intestine, liver and subcutaneous adipose tissue and affected adipose tissue fatty acid composition. Native catechins produced less pronounced effects. These results suggest that TMC down-regulate endogenous fatty acid synthesis, which should be taken into account in dietary applications of catechins.
...
PMID:The impact of catechins included in high fat diet on AMP-dependent protein kinase in apoE knock-out mice. 3290 Feb 30