• Journal of Microbiology and Biotechnology
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• v.1 no.4
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• pp.256-260
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• 1991

In B. subtilis, $\alpha$-amylase synthesis is regulated by amyR located directly on the upstream of amyE. Three different amyR alleles have been reported, amyR1, amyR2 and amyR3. Strains bearing the gra-10 mutation which confers derepression for catabolite repression has GlongrightarrowA transition mutation at ＋5 of amyR1. S1 nuclease mapping demonstrated that transcription initiated at 8 bases downstream from the -10 region of putative E$\sigma^{A}$ promoter P1 in amyR1 and gra-10. In amyR2, the major transcription initiatd at the same place and the minor, 10 bases downstream from -10 of P2. The transcript from P2 contributed approximately 15-20% of total amyE mRNA. S1 nuclease protection experiment indicated that amyE mRNA levels corresponded to the rate of synthesis assumed by specific activities of $\alpha$-amylase in culture supernatants, suggesting that $\alpha$-amylase synthesis is regulated at the level of transcription.n.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.3
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• pp.168-171
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• 1998

Sesaminol in sesame seed was postulated to have antitumor activity. The present study was performed to characterize the role of crude sesaminol extracted from sesame seed (Sesame Crude Sesaminol; SCS) on inhibiting the in vitro growth of human leukemia HL-60 cells. SCS inhibited the growth of human leukemia HL 60 cells in culture and macromolecular synthesis in a dose and time dependent manner. The cytostatic range of SCS concentration was found to be 60 to 100 $\mu\textrm{g}$/ml. SCS concentration greater than 200 $\mu\textrm{g}$/mlwere cytocidal to HL-60 cells. When SCS concentraction was 6 $\mu\textrm{g}$/mland 50 $\mu\textrm{g}$/ml the synthesis of HL-60 cells was inhibited by 35% for DNA, 6% for RNA and 5% for protein and 83% for DNA, 76% for RNA and 60% for protein. Of specific interest was the irreversible effect of SCS in inhibiting DNA synthesis of HL-60 cells. This was evidenced from the fact that, even after washed with PBS three times, preincubated HL-60 cells still showed the inhibited DNA synthesis.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.1-10
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• 1988

Previously. we reported that the intraperitoneal administration of ginseng crude saponin increased: (I) nuclear RNA polymerase activity. (2) nuclear RNA synthesis. (3) cytoplasmic RNA synthesis. (4) cytoplasmic heavy polyrioosome content. (5) amino acid incorporation in vitro of microsome and polysome isolated rat liver. and (6) the incorporation rate of labeled amino acids into serum protein. In addition, a spectacular increase in the rough endoplasmic reticulum of hepatocyte administered crude saponin for four weeks orally was shown through electron microscopy. An increase in polysomal content in membrane-hound ribosome was shown through ultracentrifugation. Recently, successive intraperitoneal. administration .of $ginsenosid-Rb_2$ was given to streptozotocin (STZ) diaoetic rats of hypoproteinemia. The blood urea nitrogen and hepatic urea concentration were decreased significantly. The total protein and alhumin levels in the serum were increased in comparison to control values. In contrast. the $ginsenoside-Rb_2$ treated group of STZ diahetic rats showed a significant increase in liver RNA. total ribosome and membrane-bound ribosomal contents. The administration of $ginsenoside-Rb_2$ increased the incorporation rate of labeled - precursor into total serum protein. Additionally $ginsenoside-Rb_2$ improved the nitrogen balance of diabetic rats. On the bases of these experimental results, ginseng saponin has a metabolic stimulatory or anabolic action on RNA and protein synthesis.

• BMB Reports
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• v.40 no.2
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• pp.156-162
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• 2007

Two lysis-defective but DNA synthesis non-defective temperature-sensitive (ts) mutants of mycobacteriophage L1, L1G23ts23 and L1G25ts889 were found to be defective also in phage-specific RNA synthesis in the late period of their growth at 42$^{\circ}C$each to the extent of 50% of that at 32$^{\circ}C$The double mutant, L1G23ts23G25ts889 showed the ts defect in phage RNA synthesis that was nearly additive of those shown individually by the two single-mutant parents. Both G23 and G25 were shown to start functioning sometimes between 30 and 45 min after infection but the former gene might be dispensable after 45 min, while the latter was not. Northern analysis also shows that at 42$^{\circ}C$>, L1G23ts23 affects RNA synthesis more strongly than L1G25ts889 from L1 DNA segments that serve as the template for late gene transcription. Among the 21 virion and 12 non-virion late proteins synthesized by L1, L1G23ts23 is defective in the synthesis of at least 9 virion and all of non-virion proteins at 42$^{\circ}C$>. In contrast, L1G25ts889 is completely defective in synthesis of all the 33 late proteins. Possible roles of G23 and G25 in the positive regulation of transcription of different sets of late genes of L1 have been discussed.

• Nutritional Sciences
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• v.3 no.2
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• pp.57-65
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• 2000

Partial enteral nutrition (PEN) supplemented with insulin-like growth factor-I (IGF-I) to neonatal piglets receiving parenteral nutrition increases lactase-phlorizin hydrolase (LPH) activity, but not LPH mRNA. The goal of the current study was to investigate the mechanism by which IGF-I up-regulates LPH activity. We hypothesized that IGF-I regulates LPH synthesis post-transcriptionally. Methods: Newborn piglets (n=15) received 100% parenteral nutrition (TPN), 80% parenteral nutrition + 20% PEN (PEN), or PEN + IGF-I (1.0mg/kg/d). On day 7, two stable isotopes of leucine, [$^2 H_3$]-leucine and [$^{13}C_1$]-L-leucine were intravenously administered to measure mucosal protein and brush LPH (BB LPH) synthesis. Results: Weight gain, nutrient intake and jejunal weight and length were similar among the treatment groups. PEN increased mucosal weight, villus width and cross-sectional area, LPH activity, mRNA expression and the abundance of proLPHh compared to 100% TPN (p<0.05). IGF-I further increased mucosal weight, LPH activity and LPH activity per unit BB LPH ~2-fold over PEN alone (p<0.05), but did not affect LPH mRNA or the abundance of proLPHh or mature LPH. Isotopic enrichment of [$^2 H_3$]-leucine and [$^{13}C_1$]-L-leucine in plasma, mucosal protein and LPH precursors, and the fractional and absolute synthesis rates of mucosal protein and LPH were similar among the treatment groups. Total mucosal protein synthesis was increased 60% (p<0.05) and LPH synthesis tended (p=0.14) to be greater in the IGF-I treated animals compared to the other two groups. Conclusions: The primary mechanism by which IGF-I up-regulates LPH may be post-translational, either via reducing LPH turnover, or by specifically altering LPH activity.

• The Microorganisms and Industry
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• v.14 no.1
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• pp.7-11
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• 1988

Efficient in vitro RNA synthesis can be easily accomplished from cloned DNA using bactrio-phage SP6, T7 or T3 RNA polymerase. Despite its popularity as in vitro transcription system, molecular mechanisms of bacteriophage transcription has not been studied, although physical and catalytic properties of several phage RNA polymerases have well been documented (1). Only recently the T7 promoter has been physically mapped by footprinting of the T7 RNA polymerase (2,3). These simple phage systems, however, could be useful for detailed molecular studies of transcription.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.254.2-254.2
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• 2003

For many viruses, -1 ribosomal frameshifting regulate protein synthesis using an RNA pseudoknot. The integrity of pseudoknot stability and structure is the important feature for efficient frameshifting. Thus, small molecules interacting with viral RNA pseudoknots would be potential antiviral agents targeting\ulcorner frameshifting system in viruses. X-ray structure of RNA pseudoknot complexed with biotin has been reported, in which biotin is bound at the interface between the pseudoknot's stacked helices. (omitted)

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.6
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• pp.1012-1022
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• 2020

Objective: Caseins and fatty acids of milk are synthesized and secreted by the epithelial cells of the mammary gland. All-trans retinoic acid (ATRA), an active metabolite of vitamin A, has been shown to promote mammary development. This study was conducted to determine the effect of ATRA on casein synthesis and fatty acid composition in MAC-T cells. Methods: MAC-T cells were allowed to differentiate for 4 d, treated with ATRA (0, 1.0, 1.5, and 2.0 μM), and incubated for 3 d. We analyzed the fatty acid composition, the mRNA expression of casein and fatty acid synthesis-related genes, and the phosphorylation of casein synthesis-related proteins of MAC-T cells by gas chromatography, quantitative polymerase chain reaction, and western blotting, respectively. Results: In MAC-T cells, ATRA increased the mRNA levels of α_S1-casein and β-casein, janus kinase 2 (JAK2) and E74-like factor 5 of the signal transducer and activator of transcription 5 β (STAT5-β) pathway, ribosomal protein S6 kinase beta-1 (S6K1) and eukaryotic translation initiation factor 4E binding protein 1 of the mammalian target of rapamycin (mTOR) pathway, inhibited the mRNA expression of phosphoinositide 3-kinase and eukaryotic initiation factor 4E of the mTOR pathway, and promoted the phosphorylation of STAT5-β and S6K1 proteins. Additionally, ATRA increased the de novo synthesis of fatty acids, reduced the content of long-chain fatty acids, the ratio of monounsaturated fatty acids to saturated fatty acids (SFA), the ratio of polyunsaturated fatty acids (PUFA) to SFA, and the ratio of ω-6 to ω-3 PUFA. The mRNA levels of acetyl-CoA carboxylase 1, fatty acid synthase, lipoprotein lipase, stearoyl-CoA desaturase, peroxisome proliferator-activated receptor gamma, and sterol regulatory element-binding protein 1 (SREBP1) were enhanced by ATRA. Conclusion: ATRA promotes the synthesis of casein by regulating JAK2/STAT5 pathway and downstream mTOR signaling pathway, and it improves the fatty acid composition of MAC-T cells by regulating SREBP1-related genes.

• Journal of Microbiology and Biotechnology
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• v.17 no.7
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• pp.1204-1207
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• 2007

Structural analyses have shown that nucleotides at the positions 770 and 771 of Escherichia coli 16S rRNA are implicated in forming one of highly conserved intersubunit bridges of the ribosome, B2c. To examine a functional role of these residues, base substitutions were introduced at these positions and mutant ribosomes were analyzed for their protein synthesis ability using a specialized ribosome system. The results showed requirement of a pyrimidine at the position 770 for ribosome function regardless of the nucleotide identity at the position 771. Sucrose gradient profiles of ribosomes revealed that the loss of protein-synthesis ability of mutant ribosome bearing a base substitution from C to G at the position 770 stems from its inability to form 70S ribosomes. These findings indicate involvement of nucleotide at the position 770, not 771, in ribosomal subunit association and provide a useful rRNA mutation that can be used as a target to investigate the physical interaction between 16S and 23S rRNA.

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.229-236
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• 2000

The synthesis of steroid hormone starts from cholesterol. Steroidogenic acute regulatory protein (StAR) acutely transfers cholesterol from the outer mitochondrial membrane to the inner in the early step of steroidogenesis. Many kinds of steroid hormone are mainly synthesized in adrenal grand, ovary, and testis. Among the steroid hormone, testosterone is synthesized in Leydig cells of the testis, the production of testosterone significantly increases in adult testis after puberty onset. Therefore, we think that the expression of StAR mRNA in testis will change according to the testicular development. The aim of this study is to determine the distribution of StAR mRNA in immature and adult rat testes and to confirm the functions of StAR in these testes. Thus, in situ hybridization was used in rat testes of the 2, 4, and 10 weeks of age. StAR mRNA was expressed in Leydig cells. Positive signals of StAR mRNA were weakly detected in Leydig cells of the 2 weeks of age. But, StAR mRNA was strongly expressed in Leydig cells of the 4 and 10 weeks of age, where steroidogenesis actively occur. In our results, the pattern of StAR mRNA expression was similar to the pattern of testosterone production in immature and adult rat testes. In conclusion, we can suggest that StAR acts as an important factor to regulate the synthesis of testosterone in Leydig cells of the rat testis.