• 미생물학회지
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• 제27권3호
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• pp.176-180
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• 1989

E. coli의 $tRNA^{phe}$내에는 세 개의 psiudouridine 염기들이 존재한다. 이 $tRNA^{phe}$내의 pseudouridine 염기들의 기능을 연구하기 위하여 부위특이적 돌연변이를 이용하여 $tRNA^{phe}$ 유전자의 염기를 다른 염기로 치환시켰다. E. coli $tRNA^{phe}$ 유전자들 중 하나인 phe W 유전자내에서 32번에 해당하는 T 염기를 C 염기로 39번 T 염기를 C 염기로 Kunkel이 개발한 부위특이적 돌연변이 방법을 사용하여 각각 치환시켰다. DNA 염기서열을 결정함으로써 돌연변이체를 확인하였으며, 이들 돌연변이 유전자를 함유한 재조합 플라스미드를 이용하여 돌연변이된 phe W 유전자들의 E. Coli NP37($pheS^{-ts}$)에 대한 complementation 활성을 조사하였다. 32번 위치가 변이된 pheW 유전자 뿐만아니라 39번 위치가 변이된 phe W 유전자를 함유한 E. coh NP37들은 모두 non-permissive temperature에서 자라지 못하였다. 이 결과는 변이된 pheW 유전자들이 E. coli NP37을 complementation 할 수 없으며, 또 pseudouridine 염기들이 생체내에서 E. coli $tRNA^{phe}$의 활성에 필수적이라는 것을 의미한다.

• Bulletin of the Korean Chemical Society
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• 제26권12호
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• pp.2093-2094
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• 2005

• Bulletin of the Korean Chemical Society
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• 제26권12호
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• pp.2033-2037
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• 2005

In vitro selection was used to isolate $Mg^{2+}$-dependent self-cleaving ribozymes with cis-cleavage activity from a pre-tRNA library having 40-mer random sequences attached to 5'-end of E. coli $tRNA^{Phe}$. After 8 rounds of SELEX (Systematic Evolution of Ligands by Exponential Enrichment), RNA molecules which can self-cleave at the high concentration of $Mg^{2+}$ were isolated. The selected ribozymes can carry out the self-cleavage reaction in the presence of 100 mM $Mg^{2+}$ but not in 10 mM $Mg^{2+}$. The cleavage sites of the ribozymes are located at +3 and +4 of $tRNA^{Phe}$, compared with +1 position of 5'-end cleavage site of pre-tRNA by RNase P. New RNA constructs deprived of its D stem-loop, anticodon stem-loop, variable loop and T stem-loop, respectively showed the cleavage specificity identical to a ribozyme having the intact tRNA structure. Also, the new ribozyme fused with both a ribozyme and $tRNA^{Leu}$ showed the cleavage activities at the various sites within its sequences, different from two sites of position +3 and +4 observed in the ribozyme with $tRNA^{Phe}$. Our results suggest that the selected ribozyme is not structural-specific for tRNA.

• Bulletin of the Korean Chemical Society
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• 제26권6호
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• pp.921-924
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• 2005

It is known that metallothionein (MT) plays a role in the scavenging of free radicals, which is produced under various stress conditions. MT may function as an antioxidant that protects against oxidative damage of DNA, protein, and lipid induced by superoxide anion, hydrogen peroxide, hydroxyl radical, nitric oxide, and peroxynitrite. This study was undertaken to test the hypothesis that MT also protects from RNA damage induced by peroxynitrite, an important reactive nitrogen species that causes a diversity of pathological processes. A cell-free system was used. RNA damage was detected by the mobility of $tRNA^{Phe}$ in electrophoresis. Cleavages on tRNA were not induced by 3-morpholinosydnomine, which produces peroxynitrite directly. MT induced tRNA damage which was site specific.

• 한국미생물·생명공학회지
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• 제18권1호
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• pp.89-93
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• 1990

재조합 pBR322-trp$^+$ 플라스미드의 숙주내 안정적 유지를 목적으로 tRNA phe 의 구조유전자인 pheW$^+$ 유전자를 pBR322-trp$^+$의 플라스미드에 도입시키고, 숙주세포로는 트립토판 생산을 위한 정상숙주 LC901의 phenylalanyl tRNA synthetase 온도감수성 변이체인 LC901-pheS-ts를 구성하여 이 온도감수성 숙주의 제한온도 (restrictive temperature)에서 재조합 trp$^+$ 플라스미드의 안정적 유지와 trp$^+$ 유전자가 미치는 효과를 조사하였다.

• 대한화학회지
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• 제41권10호
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• pp.561-565
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• 1997

• 한국잠사곤충학회지
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• 제42권1호
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• pp.14-23
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• 2000

The mitochondrial genome of domesticated silkworm (Bombyx mori) was mapped with five restriction endonucleases (BamHI, EcoRI, HindIII, PstI and XbaI), the entire genome was cloned with HindIII and EcoRI. From the end sequencing results of 5$^1$and 3$^1$region for full genome set of eleven mitochondrial clones, the seven mitochondrial genes (NADH dehydrogenase 6, ATPase 6, ATPase 8, tRN $A^{Lys}$, tRN $A^{Asp}$, tRN $A^{Thr}$ and tRN $A^{Phe}$ of mori were identified on the basis of their nucleotide sequence homology. The nucleotide composition of NADH dehydrogenase 6 was heavily biased towards adenine and thymine, which accounted for 87.76%. On basis of the sequence similarity with published tRNA genes from six insect species, the tRN $A^{Lys}$, tRN $A^{Asp}$ and tRN $A^{Thr}$ were showed stable canonical clover-leaf tRNA structures with acceptible anticodons. However, both the DHU and T$\psi$C arms of tRN $A^{Phe}$ could not form any stable stem-loop structure. The two overlapping gene pairs (tRN $A^{Lys}$ -tRN $A^{ASP}$ and ATPase8-ATPase6) were found from our sequencing results. The genes are encoded on the same strad. ATPase8 and ATPase6 overlaps (ATGATAA) which are a single example of overlapping events between abutted protein-coding genes are common, and there is evidence that the two proteins are transcribed from a single bicistronic message by initiation at 5$^1$terminal start site for ATPase8 and at an internal start site for ATPase6. Ultimately, this result will provide assistance in designing oligo-nucleotides for PCR amplification, and sequencing the specific mitochondrial genes for phylogenetics of geographic races, genetically improved silkworm strains and wild silkworm (mandarina) which is estimated as ancestal of domesticated silkworm.sticated silkworm.

• Bulletin of the Korean Chemical Society
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• 제17권10호
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• pp.951-953
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• 1996

• 대한화학회지
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• 제42권2호
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• pp.209-213
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• 1998

(η6-mesitylene) manganese (Ⅰ) tricarbonyl hexafluorophosphate[MTH-Mn (Ⅰ)]과 황산 이메틸, 피로탄산 이에틸, 과망간산 칼륨 따위 화학탐침들을 사용하여 Pseudomonas alcaligenes 5S rRNA의 고차원 구조를 분석하였다. 5S rRNA의 삼차구조에서 MTH-Mn (Ⅰ)이 강하게 절단하는 자리들은 a고리의 $G_{12}AUGG_{16}$, b-C 구역의 3'쪽 가닥, 즉$G_{51}AAGUGAAGC_{60}$, B-a구역의 $U_{65}-AGCG_{69}$, d고리의 5'쪽 가닥의 $G_{72}AUGG_{76}$ 연속부분 들이다. MTH-Mn(Ⅰ)과 그밖의 화학 탐침들을 사용하여 얻은 절단 양식들에서 우리는, MTH-Mn(Ⅰ)으로 강하게 절단되는 연속부분들이 $tRNA^{Phe}$의 L자 구조의 모서리 부분에서와 같은 주머니 구조를 이룰 것이며, 이러한 구조를 형성할 때 b-C구역과 d고리가 돌쩌귀 구실을 하는 것으로 추정한다.

• Journal of Animal Science and Technology
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• 제62권2호
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• pp.263-275
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• 2020

Studies on promoting milk protein yield by supplementation of amino acids have been globally conducted. Nevertheless, there is a lack of knowledge of what pathways affected by individual amino acid in mammary epithelial cells that produce milk in practice. Phenylalanine (PHE) and valine (VAL) are essential amino acids for dairy cows, however, researches on mammary cell levels are still lacking. Thus, the aim of this study was conducted to evaluate the effects of PHE and VAL on milk protein synthesis-related and energy-mediated cellular signaling in vitro using immortalized bovine mammary epithelial (MAC-T) cells. To investigate the effects of PHE and VAL, the following concentrations were added to treatment medium: 0, 0.3, 0.6, 0.9, 1.2, and 1.5 mM. The addition of PHE or VAL did not adversely affect cell viability compared to control group. The concentrations of cultured medium reached its maximum at 0.9 mM PHE and 0.6 mM VAL (p < 0.05). Therefore, aforementioned 2 treatments were analyzed for proteomics. Glucose transporter 1 and mammalian target of rapamycin mRNA expression levels were up-regulated by PHE (166% and 138%, respectively) (p < 0.05). Meanwhile, sodium-dependent neutral amino acids transporter type 2 (ASCT2) and β-casein were up-regulated by VAL (173% in ASCT2, 238% in and 218% in β-casein) (p < 0.05). A total of 134, 142, and 133 proteins were detected in control group, PHE treated group, and VAL treated group, respectively. Among significantly fold-changed proteins, proteins involved in translation initiation or energy metabolism were detected, however, expressed differentially between PHE and VAL. Thus, pathway analysis showed different stimulatory effects on energy metabolism and transcriptional pathways. Collectively, these results showed different stimulatory effects of PHE and VAL on protein synthesis-related and energy-mediated cellular signaling in MAC-T cells.