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Symptom
Drug
Enzyme
Compound
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Gene/Protein
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Query: EC:6.4.1.2 (
acetyl-CoA carboxylase
)
2,876
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
A candidate gene approach was carried out on a commercial line of turkeys to assess the association between fatness variability and polymorphisms of genes involved in lipid metabolism. Four restriction fragment length polymorphisms (RFLP) were typed on the
fatty acid synthase
gene (MspI/pF5), on the malic enzyme gene (HindIII/em), as well as on the
acetyl coenzyme A carboxylase
and delta9 desaturase genes. Fatness level was estimated in vivo by an ultrasonic instrument. Fat yield was assessed after slaughter by calculating the ratio of the leg skin plus subcutaneous fat weight to the whole leg weight. Finally, the lipid content was determined by extraction from the boneless leg. The 84 female turkeys sampled were full and half-sibs born from eight sires, seven of which were heterozygous for MspI/pF5 or HindIII/em RFLP and one of which was double homozygous at these loci. The analyses of variance used to compare the genotypes at each RFLP suggested a major role associated with the
fatty acid synthase
gene polymorphism in the explanation of fatness variability. One homozygous genotype for MspI/pF5 was about 1.5 standard deviations leaner than the other two homozygous genotypes. An analysis of the average effects of gene substitution confirmed the association between leanness and one allele of the
fatty acid synthase
polymorphism. It also identified a significant association between leanness and one malic enzyme RFLP allele, congruent with a strictly additive determinism for the effect associated with this polymorphism. This experiment provided new evidence of the association between both
fatty acid synthase
and malic enzyme gene polymorphisms and fatness variability in turkeys.
...
PMID:Association of fatty acid synthase gene and malic enzyme gene polymorphisms with fatness in turkeys. 1062 37
PtdCho accumulation is a periodic, S phase-specific event that is modulated in part by cell cycle-dependent fluctuations in CTP:phosphocholine cytidylyltransferase (CCT) activity. A supply of fatty acids is essential to generate the diacylglycerol (DG) precursors for phosphatidylcholine (PtdCho) biosynthesis but it is not known whether the DG supply is also coupled to the cell cycle. Although the rate of fatty acid synthesis in a macrophage cell line was dramatically stimulated in response to the growth factor, CSF-1, it was not regulated by the cell cycle. Increased fatty acid synthesis correlated with elevated
acetyl-CoA carboxylase
(
ACC
) and
fatty acid synthase
(
FAS
) steady-state mRNA levels. Cellular fatty acid synthesis was essential for membrane PL synthesis. Cerulenin inhibition of endogenous fatty acid synthesis also inhibited PtdCho synthesis, which was not relieved by exogenous fatty acids. Inhibition of CCT activity by the addition of lysophosphatidylcholine (lysoPtdCho) or temperature-shift of a conditionally defective CCT diverted newly synthesized DG to the TG pool where it accumulated. Enforced expression of CCT stimulated PtdCho biosynthesis and reduced TG synthesis. Thus, the cellular DG supply did not regulate PtdCho biosynthesis and CCT activity governs the partitioning of DG into either the PL or TG pools, thereby controlling both PtdCho and TG biosynthesis.
...
PMID:Activity of the phosphatidylcholine biosynthetic pathway modulates the distribution of fatty acids into glycerolipids in proliferating cells. 1066 65
Regulation of the gene expressions of leptin, insulin receptors and lipogenic enzymes was investigated after refeeding a fat-free diet or a 10 g/100 g corn oil diet to food-deprived rats. Plasma glucose and insulin concentrations began to increase 30 min after the feeding and further increased up until 8 h. In these rats, the expression of leptin mRNA in adipose tissue began to increase significantly only 30 min after feeding, and reached a maximum at 8-16 h. However, plasma leptin levels did not increase until 4 h after refeeding, then markedly increased and reached the maximal level after 8 h. The expression of leptin mRNA and plasma leptin concentrations generally were greater in rats fed the corn oil diet compared to those fed the fat-free diet. Insulin receptor mRNA concentrations in the liver and adipose tissue began to decrease 30 min after the refeeding, in contrast to the plasma insulin increase, and continued to decrease until 8 h. The expression of
acetyl-CoA carboxylase
and
fatty acid synthase
mRNA began to increase 4-8 h after feeding and reached maximal levels at 16-24 h. Leptin treatment suppressed the expression of lipogenic enzyme mRNA in rats fed the fat-free diet but not in corn oil-fed rats, in which the expression was suppressed by polyunsaturated fatty acids and leptin expression was higher. Thus, we suggest that the glucose and insulin-dependent expressions of leptin, insulin receptors and lipogenic enzymes are coordinately and/or mutually regulated by dietary manipulation.
...
PMID:Gene expressions of leptin, insulin receptors and lipogenic enzymes are coordinately regulated by insulin and dietary fat in rats. 1080 16
This study was designed to determine the level of inhibition of gene transcription by the reduction in insulin levels upon the onset of diabetes in spontaneously diabetic B/B rats and if reducing the level of polyunsaturated fatty acids (PUFA) in the diet will increase lipogenic enzyme activity. Control (eight animals per group) and spontaneously diabetic B/B male weanling rats (25 animals per group) were fed semipurified diets containing 20% (w/w) fat of either low (0.25) or high (1.0) polyunsaturated to saturated (P/S) fatty acid ratio. Rats were killed at the onset of diabetes [blood glucose level of approximately/= 100 mg/dL (5.55 mM)] and as they became highly diabetic [blood glucose level of approximately/= 400 mg/dL (22.22 mM)]. Total RNA was extracted from liver, and the relative amount of mRNA coding for
fatty acid synthase
(
FAS
),
acetyl-CoA carboxylase
, malic enzyme, pyruvate kinase, and phosphoenolpyruvate carboxykinase was determined. Liver enzyme activities were also measured. The mRNA levels for
FAS
,
acetyl-CoA carboxylase
, and malic enzyme decreased compared to control animals. The mRNA level for pyruvate kinase decreased at the onset of diabetes as compared to control animals. Feeding animals the low P/S diet treatment elevated the level of mRNA and lipogenic enzyme activity compared to animals fed the high P/S diet treatment, suggesting that the effect of PUFA on lipogenic enzymes is through a direct effect on gene expression.
...
PMID:Dietary fat-induced suppression of lipogenic enzymes in B/B rats during the development of diabetes. 1085 27
The fatty liver dystrophy (fld) mutant mouse is characterized by neonatal fatty liver and hypertriglyceridemia that resolve at weaning, and neuropathy affecting peripheral nerve in adulthood. We now report additional significant manifestations of this single gene mutation, which include adipose tissue deficiency, glucose intolerance, and increased susceptibility to atherosclerosis. In adult fld/fld mice, both white and brown fat pads exhibit an 80% reduction in mass compared with wild-type controls, and consist of immature adipocytes as assessed by morphological and molecular criteria. The lack of lipid accumulation in fld/fld adipose tissue could be attributed, in part, to a failure to induce expression of lipoprotein lipase and enzymes involved in fatty acid synthesis, such as
fatty acid synthase
and
acetyl-CoA carboxylase
. Related to the deficiency of adipose tissue, fld/fld mice were also found to exhibit profound glucose intolerance, modest hyperinsulinemia, and reduced tissue response to insulin. As insulin resistance is a important risk factor in vascular disease, we examined susceptibility of fld/fld mice to diet-induced atherosclerosis. Mutant mice fed an atherogenic diet developed 2-fold greater aortic lesions than their wild-type counterparts, despite having a less atherogenic lipoprotein cholesterol profile. The fld adipose-deficient phenotype has both similarities to and distinctions from the group of rare human diseases known as lipodystrophies.
...
PMID:Adipose tissue deficiency, glucose intolerance, and increased atherosclerosis result from mutation in the mouse fatty liver dystrophy (fld) gene. 1088 87
R1128 substances are anthraquinone natural products that were previously reported as non-steroidal estrogen receptor antagonists with in vitro and in vivo potency approaching that of tamoxifen. From a biosynthetic viewpoint, these polyketides possess structurally interesting features such as an unusual primer unit that are absent in the well studied anthracyclic and tetracyclic natural products. The entire R1128 gene cluster was cloned and expressed in Streptomyces lividans, a genetically well developed heterologous host. In addition to R1128C, a novel optically active natural product, designated HU235, was isolated. Nucleotide sequence analysis of the biosynthetic gene cluster revealed genes encoding two ketosynthases, a chain length factor, an acyl transferase, three
acetyl-CoA carboxylase
subunits, two cyclases, two oxygenases, an amidase, and remarkably, two acyl carrier proteins. Feeding studies indicate that the unusual 4-methylvaleryl side chain of R1128C is derived from valine. Together with the absence of a dedicated ketoreductase, dehydratase, or enoylreductase within the R1128 gene cluster, this suggests a functional link between fatty acid biosynthesis and R1128 biosynthesis in the engineered host. Specifically, we propose that the R1128 synthase recruits four subunits from the endogenous
fatty acid synthase
during the biosynthesis of this family of pharmacologically significant natural products.
...
PMID:Cloning, nucleotide sequence, and heterologous expression of the biosynthetic gene cluster for R1128, a non-steroidal estrogen receptor antagonist. Insights into an unusual priming mechanism. 1093 52
Epidemiological studies have suggested that repeated weight cycling over time may increase the risk of coronary heart disease. The mechanism involved remains poorly understood, but the change in lipid metabolism during weight cycling has been offered as a possible explanation. The present study investigated the effect of weight cycling on the size and fatty acid composition of rat fat pads as well as serum cholesterol, triglyceride, glucose, insulin, and glucagon in rats. Two consecutive weight cycles were induced by 40% energy restriction followed by ad libitum refeeding of either a moderate-fat (MF; 22% energy) or a high-fat (HF; 45% energy) diet. The lipogenic enzymes, including
fatty acid synthase
,
acetyl-CoA carboxylase
, malic enzyme, pyruvate kinase, and lipoprotein lipase in the weight-cycled (WC) rats fed only the HF diet, yielded an overshoot of activities at the end of two weight cycles. These changes were accompanied by an 80% increase in the size of the adipocyte and a 40-50% increase in the size of perirenal and epididymal fat tissues in HF-WC rats. Regardless of whether the rats were fed the HF or MF diet, all WC rats showed a gradual reduction in linoleic and alpha-linolenic acid and an increase in palmitic, palmitoleic, and stearic acid in total body lipid. It is concluded that weight cycling in rats may promote body fatness if an HF diet is consumed and can significantly alter whole body fatty acid balance irrespective of whether they consumed an MF or HF diet. Most importantly, the weight cycling led to an overshoot or fluctuation of serum cholesterol, triglyceride, glucose, insulin, and glucagon. If weight cycling is associated with an increased risk of cardiovascular disease, then, part of the mechanism may involve the changes in these risk factors.
...
PMID:Weight cycling-induced alteration in fatty acid metabolism. 1095 77
To gain insights into the regulation of fat synthesis, we have investigated the effect of cold environmental exposure and feed restriction of sheep on activity and immunodetectable protein content of
acetyl-CoA carboxylase
(
ACC
) and
fatty acid synthase
in adipose tissue. Subcutaneous and mesenteric adipose tissues were collected at slaughter from sheep exposed to either cold (0+/-2 degrees C) or warm (23+/-2 degrees C) environment, and given either ad libitum or restricted access to feed for three 5-wk periods.
Acetyl-CoA carboxylase
was isolated from frozen adipose tissue samples and activity determined as the rate of incorporation of H14CO3- into acid stable malonyl-CoA. Cold exposure and feed restriction reduced (P < .05)
ACC
activity in the two adipose tissue depots. Western blot analysis with peroxidase-conjugated streptavidin showed that both adipose tissue depots express a single isoform of
ACC
. In s.c. adipose tissue, cold exposure increased (P < .05)
ACC
protein abundance, which is opposite to the change in activity. However, feed restriction reduced immunodetectable
ACC
protein. There was no significant effect of environment or feeding level on
ACC
protein abundance in mesenteric tissue. Fatty acid synthase activity determined in ammonium sulfate extract by measuring the malonyl-CoA- and acetyl-CoA-dependent oxidation of NADPH was decreased (P < .05) by feed restriction in both s.c. and mesenteric tissues. Cold exposure reduced
fatty acid synthase
activity in s.c. but not in mesenteric tissue. There was no effect of environment on
fatty acid synthase
protein abundance in either adipose tissue depot. However, feed restriction significantly reduced
fatty acid synthase
protein abundance in the two depots. The data suggest that feed restriction and exposure of ruminants to cold environmental conditions may significantly down-regulate the activity of key lipogenic enzymes.
...
PMID:Acetyl-CoA carboxylase and fatty acid synthase activity and immunodetectable protein in adipose tissues of ruminants: effect of temperature and feeding level. 1098 14
Endogenous fatty acid synthesis has been observed in some rapidly proliferating cells and tissues, both normal and neoplastic, and probably supports membrane synthesis. Sterol regulatory element binding proteins (SREBPs) are transcription factors that regulate the expression of genes for both cholesterol and fatty acid synthesis. The inactive precursor form resides in cytoplasmic membranes. Intracellular lipid depletion triggers proteolytic cleavage of SREBP, allowing the amino terminus to enter the nucleus and activate the expression of enzymes, including
acetyl-CoA carboxylase
(
ACC
) and
fatty acid synthase
(
FAS
), major biosynthetic enzymes for fatty acid synthesis. The expression patterns of
ACC
,
FAS
, SREBP, and Ki-67 in fetal tissues were compared to determine whether SREBP is likely to participate in the regulation of proliferation-associated fatty acid synthesis during fetal growth. Tissues from 22 fetuses, 12 first-trimester and 10 second-trimester (range 7.0 to 21.6 weeks), were studied. Serial 5-microm sections were stained with antibodies to
ACC
,
FAS
, SREBP, and Ki-67 and were compared.
ACC
,
FAS
, SREBP, and Ki-67 were coexpressed in the proliferative compartments of the intestines, skin, and kidney.
ACC
,
FAS
, and Ki-67 were coexpressed with little SREBP in lung and cytotrophoblast. SREBP,
ACC
, and
FAS
were coexpressed without Ki-67 in hepatocytes, ganglion cells, and intermediate trophoblast. The close linkage of SREBP,
ACC
,
FAS
, and Ki-67 in some proliferating fetal tissues suggests that in these tissues SREBP participates in the transcriptional regulation of lipogenic genes during proliferation. SREBP,
ACC
, and
FAS
coexpression without Ki-67 occurs in differentiated tissues that may synthesize fatty acids for other functions.
...
PMID:Lipogenic enzymes fatty acid synthase and acetyl-coenzyme A carboxylase are coexpressed with sterol regulatory element binding protein and Ki-67 in fetal tissues. 1100 Mar 30
The objectives of the present study were to examine the effect of a milk fat-depressing (MFD) diet on: 1) the activity of mammary
acetyl-CoA carboxylase
(
ACC
) and
fatty acid synthase
(
FAS
), 2)
ACC
mRNA relative abundance and 3) distributions of conjugated linoleic acids (CLA) and trans-18:1 fatty acids (tFA) in milk fat. Twelve lactating Holstein cows were used in a single reversal design. Two diets were fed: a control diet (60:40% forage/concentrate) and an MFD diet (25:70% forage/concentrate, supplemented with 5% soybean oil). The MFD diet decreased (P: < 0 0.001) milk fat by 43% and
ACC
and
FAS
activity by 61 and 44%, respectively. A reduced
ACC
mRNA relative abundance (P: < 0.001) corresponded with the lower
ACC
activity. The fatty acids synthesized de novo were decreased (P: < 0. 002), whereas tFA were increased from 1.9 to 15.6% due predominantly to a change in trans-10-18:1 isomer (P: < 0.001). With the MFD diet, the trans-7, cis-9 and trans-10, cis-12 CLA isomers were elevated (P: < 0.001), in contrast to the decrease in trans-11-18:1 (P: < 0. 001) and cis-9, trans-11-18:2. The data were consistent with a dietary effect on mammary de novo FA synthesis mediated through a reduction in
ACC
and
FAS
activity and in
ACC
mRNA abundance. The results were compatible with a role of trans-10, cis-12 CLA in milk fat depression, but alterations noted in tFA and other CLA isomers suggest that they also may be important during diet-induced milk fat depression.
...
PMID:Mammary lipogenic enzyme activity, trans fatty acids and conjugated linoleic acids are altered in lactating dairy cows fed a milk fat-depressing diet. 1101 91
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