• Microbiology and Biotechnology Letters
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• v.21 no.5
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• pp.473-477
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• 1993

Both glycerol-phosphate acyltransferase (GPAT) and 7.2 kb mRNAs were present at the highest level in liver. Glycerol-phosphate acyltransferase and 7.2 kb mRNA levels increased dramatically when fasted mice were refed a high carbohydrate diet. In mature 3T3-L1 adipocytes, insulin increased both glycerol-phosphate acyltransferase and 7.2kb mRNA levels 2.6 to 3-fold while dibutyryl cAMP decreased mRNA levels by 50% and 80%, respectively. These results indicate positive regulation by insulin and negative regulation by dibutyryl cAMP of both glycerol-phosphate acyltransferase and 7.2 kb mRNA.

• Korean Journal of Microbiology
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• v.48 no.3
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• pp.207-211
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• 2012

Autoinduction is mediated by signaling molecules known as autoinducers (AIs) that are produced, released and detected by bacterium itself. We recently reported that Corynebacterium glutamicum possesses an autoinduction system which secretes autoinducers during the stationary-phase of growth, triggering the expression of acyltransferase gene. However, it is still not clear what may act as autoinducers for the autoinduction in C. glutamicum. In this study, we compared the inducing effects of cell-free culture fluids obtained from a number of microbes including Agrobacterium tumefaciens, Vibrio harveyi, and Escherichia coli. Fluids from A. tumefaciens did not increase the expression of acyltransferase, whereas fluids from V. harveyi BB120 ($AI-1^+$, $AI-2^+$) did. Interestingly, the expression was increased by the fluids obtained from the early exponential-phase culture of BB120. Furthermore, this induction was not observed by the fluids from autoinducer mutants of V. harveyi MM77 ($AI-1^-$, $AI-2^-$) and BB152 ($AI-1^-$, $AI-2^+$). Unlike the effect shown by BB152, fluids from E. coli ($AI-1^-$, $AI-2^+$) still induced the acyltransferase expression. Taken together, these results suggest that C. glutamicum autoinducers seem to be unidentified molecules which do not belong to AI-1 or AI-2.

• Journal of Microbiology and Biotechnology
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• v.16 no.7
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• pp.1163-1168
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• 2006

The recombinant plasmid pLEX2FP complements the mutation in Zoogloea ramigera 115MM1, and the complemented mutant produces an exopolysaccharide that shows higher affinity for the calcofluor dye than the exopolysaccharide from Z. ramigera 115SLR, resulting in higher fluorescence intensity under UV light. A compositional and structural analysis of the exopolysaccharide from Z. ramigera 115MM1 showed that the different fluorescent properties were due to a lower content of acetyl groups when compared with Z. ramigera 115SLR exopolysaccharide. These results were in agreement with a sequence analysis of the gene carried in the plasmid pLEX2FP, which appeared to encode an O-acyltransferase highly homologous to the 3-O-acyltransferase of Streptomyces mycarofaciens. The gene encoding the acyltransferase from Z. ramigera 115SLR was expressed as a GST-fusion protein with 70,000 daltons in E. coli.

• Korean Journal of Pharmacognosy
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• v.32 no.3 s.126
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• pp.193-199
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• 2001

The inhibitory effects of methanol extracts of 135 medicinal herbs on diacylglycerol acyltransferase (DGAT) activity were investigated. DGAT was partially purified from rat liver. Eleven kinds of methanol extracts of medicinal herbs including Evodiae Fructus showed a mild inhibitory effect with the concentration of $125\;{\mu}g/ml$ (above 40% inhibition). Six kinds of methanol extracts including Ephedrae Herba exhibited a weak inhibition. Among them, three kinds of butanol extracts (Sophorae Radix, Arecae Semen, Caesalpiniae Lignum) and the chloroform extracts of Evodiae Fructus showed significant inhibitory activities (above 60% inhibition) at the same concentration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.958-962
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• 1999

Hydroxy methylglutaryl CoA(HMG CoA) reductase and acyl CoA:cholesterol acyltransferase(ACAT) are two important enzymes that are associated with regulation of cholesterol metabolism. The inhibitors of HMG CoA reductase and ACAT are very effective in lowering serum cholesterol in most animal species. In present study, various plant extracts with hot water were used to examine the inhibitory activities against HMG CoA reductase and ACAT that are involved in cholesterol biosynthesis and cholesterol esterification in tissues, respectively. The extracts of Fagophyrum rotundatum, Rosa multiflora, Rosa rugosa and Alisma orientalis exhibited significant inhibitory activities against the ACAT, 29%, 24%, 19%, and 18%, respectively. However the extracts of Typha augustifolia, Polygonum cuspidatum, Crataegus pinnatifida, Polygonum multiflorum inhibited the HMG CoA reductase activity by 53%, 42%, 37%, and 33% respectively. Results suggest that these plant extracts might play important roles in the regulation of the cholesterol metabolism in vivo.

• Archives of Pharmacal Research
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• v.28 no.2
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• pp.164-168
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• 2005

The EtOAc extract of Youngia koidzumiana significantly inhibited the diacylglycerol acyltransferase (DGAT) from rat liver microsomes. Bioactivity-guided fractionation led to the isolation of nine compounds, the structures of which were established using physicochemical and spectral data. Of the isolated compounds, oleanolic acid (2), methyl ursolate (7) and corosolic aicd (8) inhibited DGAT, with $IC_{50}$ values of 31.7, 26.4, and $44.3{\mu}M$, respectively. However, sesquit-erpenoids showed only weak inhibitory effects toward DGAT.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.446-448
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• 2002

The inhibitory activity of tanshinones from Salvia miltiorrhiza was tested on rat liver diacylglycerol acyltransferase (DGAT). Cryptotanshinone (1) and 15,16-dihydrotanshinone I (3) exhibited potent DGAT inhibitory activities dose-dependently with $IC_{50}$ values of $10.5 {\;}{\mu\textrm{g}}/ml{\;}and{\;}11.1{\;}{\mu\textrm{g}}/ml$. However, tanshinone IIA (2) and tanshinone I (4) showed very weak inhibition ($IC_{50}{\;}value:{\;}>{\;}250{\;}{\mu\textrm{g}}/ml$). A dihydrofuran moiety was seemed to be responsible for the stronger inhibitory activity

• Journal of Ginseng Research
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• v.19 no.3
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• pp.212-218
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• 1995

A human hepatoma cell line, hep G2, was used to investigate the mechanism of serum cholesterol reduction by ginseng total saponin, ginsenoside-$Rb_1$, - $Rb_2$, and non-saponin fraction (ether extraction). Hep G2 cells were incubated in 10 $\mu\textrm{g}$/ml of cholesterol containing serum free-RPMl1640 medium with various concentration of ginseng components. The amounts of cholesterol in Hep G2 cells were decreased to maximum 51% in total saponin or two ginsenoside-treated groups while there was 137% increase in cholesterol level of control group as compared with that of normal group. Nonsaponin groups did not show the same effect. In order to elucidate the observed changes in the amount of cholesterol, the activity of amyl CoA : cholesterol acyltransferase (ACAT) in groups showing remarkable reduction in cholesterol amount, i.e., total saponin 10-6%, ginsenoside-$Rb_1$ $10^{-4}$%, ginsenoside-$Rb_2$, $10^{-4}$%, and non-saponin fraction $10^{-4}$%, was assayed using [1-$^{-14}C$%]oleic acid as enzyme substrate. The activity of ACAT was increased in all groups tested as compared with that of control group except for non-saponin group cultured in water soluble cholesterol containing medium. The serum cholesterol lowering effects of ginseng components can partially be attributed to the increased hepatocellular ACAT activity.

• Animal Bioscience
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• v.36 no.2
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• pp.175-190
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• 2023

Objective: The study was conducted to screen differentially expressed long noncoding RNA (lncRNA) in chickens by high-throughput sequencing and explore its mechanism of action on intramuscular fat deposition. Methods: Herein, Rose crown and Cbb broiler chicken embryo breast and leg muscle lncRNA and mRNA expression profiles were constructed by RNA sequencing. A total of 96 and 42 differentially expressed lncRNAs were obtained in Rose crown vs Cobb broiler chicken breast and leg muscle, respectively. lncRNA-ENSGALT00000046546, with high interspecific variability and a potential regulatory role in lipid metabolism, and its predicted downstream target gene 1-acylglycerol-3-phosphate-O-acyltransferase 2 (AGPAT2), were selected for further study on the preadipocytes. Results: lncRNA-46546 overexpression in chicken preadipocyte 2 cells significantly increased (p<0.01) the expression levels of AGPAT2 and its downstream genes diacylglycerol acyltransferase 1 and diacylglycerol acyltransferase 2 and those of the fat metabolism-related genes peroxisome proliferator-activated receptor γ, CCAAT/enhancer binding protein α, fatty acid synthase, sterol regulatory element-binding transcription factor 1, and fatty acid binding protein 4. The lipid droplet concentration was higher in the overexpression group than in the control cells, and the triglyceride content in cells and medium was also significantly increased (p<0.01). Conclusion: This study preliminarily concludes that lncRNA-46546 may promote intramuscular fat deposition in chickens, laying a foundation for the study of lncRNAs in chicken early embryonic development and fat deposition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.3
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• pp.371-379
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• 1994

The effect of milk in low and high cholesterol diets were investigated on serum cholesterol esterification. Weanling male Sprague-Dawley rats were divided into low(0.01% w/w) and high (1.01% w/w) cholesterol-diets groups. Bothlow and high cholesterol groups were consisted of three groups : control , LM(low heat milk), and HM (high heat milk) groups. After feeding these experimental diets for six weeks, serum cholesterol (free cholesterol and cholestryl ester) concentration and activity of lecithin.: cholesterol acyltransferase (LCAT) were measured, and serum lipoprotein profile was examined using gel column chromatography. According to the result, activity of LCAT was elevated independently by intakes of high cholesterol and milk , which resulted in the increase of daily turnover of serum cholesteryl ester. However, the turnover of HDL-cholesteryl ester increased only by milk. LCAT activity was moderately correlated with levels of total-and HDL-free choelsterol. It is concluded from the present study that milk had the cholesterol-lowering effect which partly appears to be mediated through facilitated reverse cholesterol transport.