• Applied Biological Chemistry
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• v.5
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• pp.7-21
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• 1964

가잠(家蠶)(Bombyx mori)의 잠체(蠶體), 용체 및 견사선(絹絲腺)(후부(後部))에서 phenol법(法)으로 RNA를 추출(抽出)하여 RNA의 nucleotide 조성(組成)(mole ratio)을 살피는 한편, 견사선(絹絲腺)(후부(後部))에서 초원심법(超遠沈法)으로 r-RNA, s-RNA를 분리(分離)하여 이에 대(對)한 nucleotide조성(組成)을 조사(調査)하고 또 가잠견사선(家蠶絹絲腺)과 비교(比較)할 목적(目的)으로 거미 방적선(紡績腺)의 t-RNA를 분리(分離)하여 nucleotide성분(成分)을 측정(測定)하여 다음과 같은 결과(結果)를 얻었다. 1) 잠란(蠶卵)에 있어서 이것을 마수(磨粹), 탈지(脫脂) 후(後) lysozyme을 작용(作用)시키고 10% NaCl용액(溶液)으로 가열(加熱) 추출(抽出)하는 새방법(方法)을 고찰(考察)하여 RNA의 추출(抽出)이 극난(極難)한 잠란(蠶卵)에서 RNA를 분리(分離)하는데 성공(成功)하였다. 2) 가잠란(家蠶卵), 잠체(蠶體), 용체 및 견사선(絹絲腺)(후부(後部))의 t-RNA nucleotide 조성(組成)은 다음과 같다. 시료(試料) $\frac{G+C}{A+U}$ $\frac{G+U}{A+C}$ $\frac{Pu}{Py}$ 가잠란(家蠶卵)의 RNA 1.14 1.24 0.99 가잠체(家蠶體)의 RNA 1.40 1.36 0.80 용체의 RNA 1.40 1.33 1.35 후부견사선(後部絹絲腺)의 RNA 1.05 1.32 1.15 이로서 잠체(蠶體). 용체 및 견사선(絹絲腺)의 Pu/Py는 각각(各各) 차이(差異)가 있으나 G+U/A+C는 3자간(者間)에 1.3의 거이 동일(同一)한 수치(數値)를 보여주고 있다. G+C/A+U는 잠체(蠶體)와 용체에 있어서 동일(同一)하나 견사선(絹絲腺)의 그것과는 차이(差異)가 있다. 한편 잠란(蠶卵)에 있어서는 Pu/Py, G+C/A+U, G+U/A+C가 각각(各各) 잠체(蠶體), 용체 및 견사선(絹絲腺)에 있어서와 현저(顯著)한 차이(差異)를 보여주고 있다. G+C/A+U가 1.3이나 되는 RNA의 base ratio를 가진 생물(生物)에 관(關)해서는 아직 보고(報告)된 바 없고 다만 본논문(本論文)의 가잠(家蠶)에 관(關)한 RNA와 속편(續編)인 각종(各種) 패류(貝類) RNA의 nucleotide 조성(組成)에서 모두 1.3에 가까운 수치(數値)를 보여주고 있다. 3) 견사선(絹絲腺)(후부(後部)) t-RNA와 거미 방적선(紡績腺)의 t-RNA의 nucleotide molar ratio 및 견사선(絹絲腺)의 r-RNA, s-RNA nucleotide 조성(組成)은 다음과 같다. 재료(材料) $\frac{G+C}{A+U}$ $\frac{G+U}{A+C}$ $\frac{Pu}{Py}$ 가잠견사선(家蠶絹絲腺)(후부(後部)의 t-RNA 1.05 1.32 1.15의 r-RNA 1.12 1.30 1.20의 s-RNA 1.55 1.33 0.65 지주방적선(蜘蛛紡績腺)의 t-RNA 1.35 1.24 1.16 즉(卽) 가잠견사선(家蠶絹絲腺)(후부(後部))과 거미방적선(紡績腺)의 t-RNA nucleotide 조성(組成)은 Pu/Py가 1.15와 1.16으로서 거이 동일(同一)하지만 G+C/A+U, G+U/A+C에 차이(差異)가 있음을 보았다. 한편 가잠견사선(家蠶絹絲腺)(후부(後部)) r-RNA와 s-RNA의 Pu/Py와 G+C/A+U는 현저(顯著)한 차이(差異)가 있고, G+U/A+C에 있어서는 1.3으로서 거이 동일(同一)한 수치(數値)를 보여주고 있다. 4. 이상(以上)과 같이 잠체(蠶體)에 관(關)한 RNA의 nucleotide 조성(組成)은 소위(所謂) GC-type로서, 현재(現在)까지 문헌(文獻)에 보고(報告)된 각종(各種) 생물(生物)의 RNA의 base ratio에 관(關)하여 비교(比較) 검토(檢討)하였으며, RNA의 nucleotide ratio의 차이(差異)의 의의(意義)에 대(對)하여 고찰(考察)하였다.

• Journal of Sericultural and Entomological Science
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• v.3
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• pp.23-28
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• 1963

The RNA content of fertilized egg of Bombyx mori was shown a continuing great increase reaching peak at the 5th day after egg laying and a slight decrease there after. Such a change of RNA content is considered to be directly associated with the formation and development of egg embryo of silk worm. (2) The RNA content of nonfertilized egg is much less than that of fertilized one at first day of egg laying and it increased slightly until 4 th day after egg laying then decreased. (3) The RNA content of fertilized egg irradiated by gamma-ray (3,000 r) was shown a slight increase until 2nd day after irradiation, but no change was observed there after. This fact shows that irradiation suppressed the biosynthesis of RNA silk worm egg. (4) The RNA content of HCl treated silk worm egg was shown a continuing steep rise until 7 th day after the acid treat, while no change was observed in the non-treated egg. The RNA content of HCl treated egg with irradiation of gamma-ray (1,500 r), decreased until 3 rd day after irradiation in contrast to that of non-irradiated group, but it increased rapidly from 4 th day until 7 th day after acid treating.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.909-915
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• 2005

We investigated microRNA (miRNA) biogenesis of Epstein-Barr virus (EBV) which is the first virus shown to produce viral miRNAs. As expected, expression of all the reported EBV miRNAs were detected by Northen blot in an EBV-infected B cell line, B95-8; BHRF1-1, BHIU1-2, BHRF1-3, BART1, and BART2. The putative EBV pri-miRWAs and pre-miRNAs predicted from the known mature EBV miRNA sequences were detected by RT-PCR in B95-8 cells. Many animal miRNA genes exist as clusters of 2-7 genes and they are expressed polycistronically. As the EBV miRNAs are clustered in two regions of the EBV genome, we examined whether these clustered EBV miRNA genes are also expressed polycistronically. A long polycistronic transcript with the expected size (1602 bp) corresponding to the BHRF1-1~BHRF1-2~BHRF1-3 was amplified. However, any polycistronic transcript containing both BART1 and BART2 was detectable in B95-8. These results suggest that EBV miRNAs may be processed in a similar way with animal miRNAs and that some of the clustered EBV miRNAs can be transcribed polycistronically.

• Molecules and Cells
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• v.42 no.7
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• pp.523-529
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• 2019

mRNA quality is controlled by multiple RNA surveillance machineries to reduce errors during gene expression processes in eukaryotic cells. Nonsense-mediated mRNA decay (NMD) is a well-characterized mechanism that degrades error-containing transcripts during translation. The ATP-dependent RNA helicase up-frameshift 1 (UPF1) is a key player in NMD that is mostly prevalent in the cytoplasm. However, recent studies on UPF1-RNA interaction suggest more comprehensive roles of UPF1 on diverse forms of target transcripts. Here we used subcellular fractionation and immunofluorescence to understand such complex functions of UPF1. We demonstrated that UPF1 can be localized to the nucleus and predominantly associated with the chromatin. Moreover, we showed that UPF1 associates more strongly with the chromatin when the transcription elongation and translation inhibitors were used. These findings suggest a novel role of UPF1 in transcription elongation-coupled RNA machinery in the chromatin, as well as in translation-coupled NMD in the cytoplasm. Thus, we propose that cytoplasmic UPF1-centric RNA surveillance mechanism could be extended further up to the chromatin-associated UPF1 and co-transcriptional RNA surveillance. Our findings could provide the mechanistic insights on extensive regulatory roles of UPF1 for many cellular RNAs.

• Journal of fish pathology
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• v.6 no.2
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• pp.93-101
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• 1993

The RNAI mutation of Saccharomyces cerevisia is a recessive and temperature sensitive lethal mutation which interferes with the production of mRNA, rRNA, and tRNA. However, the precise role of RNAI gene have not been revealed until yet. We have cloned rna1-1 mutant gene from rna1-1 mutant yeast strain(R49 ; trpl, ura3-52, rna1-1). The 3.4kb BglII fragment of wild type RNAI clone(81-2-6) contains whole RNAI gene. The genomic southern blotting with BglII digested R49 genomic DNA as a probe shows the unique and identical band with wild type 3.4kb BglII fragment. Therefore, We prepared partial BglII genomic library(3~4kb BglII fragments) into BamH I site of pUC19. The rna 1-1 mutant clone was screened with Digoxigenin(DIG)-lableled probe by high density colony hybridization. The 5'-flanking region of rna1-1 gene was sequenced by dideoxy chain termination method. The 5'-flanking sequence of RNAI gene contains three TATA-like sequence ; TAATA, TATA and TTTTAA at position of -67, -45, and -36 from first ATG codon respectively. The 5'-flanking region of wild type RNA I gene from ATG codon to -103nt was deleted with Bal31 exonuclease digestion, generating $pUC{\Delta}$/RNA I. After constructing $pYEP{\Delta}RNA$ I (consists of -103nt deleting RNA I gene, URA3 gene, $2{\mu}m$ rep. origin), pYEPrna1-1(consists of Xba I fragment of pUCrna1-1. URA3 gene, $2{\mu}m$ rep. origin), and pYEPRNAI. each plasmid was transformed into host strain(trpl, ura3-52, rna1-1) by electroporation, respectively. Yeast transformant carrying $pYEP{\Delta}RNA$ I did not complement the thermal sensitivity of rna1-1 gene. It means that TATA-like sequences in 5'-flanking region is not TATA sequence for transcribing RNAI gene and there may be other essential sequence in upstream region for the transcription of RNAI gene.

• Tuberculosis and Respiratory Diseases
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• v.56 no.4
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• pp.393-404
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• 2004

Background : Nucleic acid hybridization has become an essential technique in the development of our understanding of gene structure and function. The quantitative analysis of hybridization has been used in the measurement of genome complexity and gene copy number. The filter hybridization assay is rapid, sensitive and can be used to measure RNAs complementary to any cloned DNA sequence. Methods : The authors assessed the accuracy, linearity, correlation coefficient and specificity of the hybridization depending on the added dose(0, 1, 5, and $10{\mu}g$) of non-specific rat spleen RNA to hybridization of surfactant protein A mRNA. Filter hybridization assays were used to obtain the equation of standard curve and thereby to quantitate the mRNA quantitation. Results : 1. Standard curve equation of filter hybridization assay between counts per minute (X) and spleen RNA input (Y) was Y=0.13X-19.35. Correlation coefficient was 0.98. 2. Standard curve equation of filter hybridization assay between counts per minute (X) and surfactant protein A mRNA transcript input (Y) was Y=0.00066X-0.046. Correlation coefficient was 0.99. 3. Standard curve equation of filter hybridization assay between counts per minute (X) and surfactant protein A mRNA transcript input (Y) after the addition of $1{\mu}g$ spleen RNA was Y=0.00056X-0.051. Correlation coefficient was 0.99. 4. Standard curve equation of filter hybridization assay between counts per minute (X) and surfactant protein A mRNA transcript input (Y) after the addition of $5{\mu}g$ spleen RNA was Y=0.00065X-0.088. Correlation coefficient was 0.99. 5. Standard curve equation of filter hybridization assay between counts per minute (X) and surfactant protein A mRNA transcript input (Y) after the addition of $10{\mu}g$ spleen RNA was Y=0.00051X-0.10. Correlation coefficient was 0.99. Conclusions : Comparison of cpm/filter in a linear range allowed accurate and reproducible estimation of surfactant protein A mRNA copy number irrespective of the addition dosage of non-specific rat spleen RNA over the range $0-10{\mu}g$.

• Journal of Plant Biology
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• v.26 no.1
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• pp.1-6
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• 1983

In order to investigate the effects of GA3 on RNA biosynthesis, the amounts of rRNA and tRNA in germinating maize seeds were measured. The amount of rRNA in the endospermless seedlings was remarkably increased by GA3 tretment after 48 h of germination, but no effect was observed after 12 h of germination. While the amout of rRNA in 0.5 cm shoots in length was decreased by GA3 treatment, both of the amounts of rRNA and tRNA were increased in 1~1.5 cm shoots. According to the above mentioned results, it may be suggested that RNA biosynthesis is affected by GA3 treatment, and that GA3 participates in the biosynthesis of rRNA rather than tRNA in germinating maize seeds.

• Bulletin of the Korean Chemical Society
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• v.29 no.6
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• pp.1137-1140
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• 2008

M1 RNA, the catalytic subunit of Escherichia coli RNase P, is an essential ribozyme that processes the 5' leader sequence of tRNA precursors (ptRNAs). Using KS2003, an E. coli strain generating only low levels of M1 RNA, which showed growth defects, we examined whether M1 RNA is involved in polycistronic mRNA processing or degradation. Microarray analysis of total RNA from KS2003 revealed six polycistronic operon mRNAs (acpP-fabF, cysDNC, flgAMN, lepAB, phoPQ, and puuCBE) showing large differences in expression between the adjacent genes in the same mRNA transcript compared with the KS2001 wild type strain. Model substrates spanning an adjacent pair of genes for each polycistronic mRNA were tested for RNase P cleavage in vitro. Five model RNAs (cysNC, flgMN, lepAB, phoPQ, and puuBE) were cleaved by RNase P holoenzyme but not by M1 RNA alone. However, the cleavages occurred at non-ptRNA-like cleavage sites, with much less efficiency than the cleavage of ptRNA. Since cleavage products generated by RNase P from a polycistronic mRNA can have different in vivo stabilities, our results suggest that RNase P cleavage may lead to differential expression of each cistron.

• Journal of Microbiology
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• v.41 no.4
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• pp.300-305
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• 2003

Intracellular expression of RNA decoys, such as TAR or RRE decoy, has been previously shown to protect immune cells from human immunodeficiency virus type 1 (HIV-1) replication by inhibiting the binding of the HIV-1 regulatory protein to the authentic HIV RNA sequence. However, HIV-1 challenge experiments of primary human T cells, which express the RNA decoy, demonstrated that the cells were only transiently protected, and hence, more improved protocols for HIV-1 inhibition with the RNA decoys need to be developed. In this report, in order to develop a more effective RNA decoy, we analyzed and compared the ability of a series of RNA decoy derivatives in inhibiting HIV-1 replication in CEM cells. Using an improved tRNA cassette to express high levels of RNA decoy transcripts in cells, we found that co-expression of both TAR and RRE decoys, in the form of an aligned sequence in a single transcription cassette, much more potently blocked cells from HIV-1 than the expression of only one kind of RNA decoy. This observation will have an important implication for experiments involving optimization of clinical applications in RNA decoy-based gene therapy against HIV-1.

• Bioinformatics and Biosystems
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• v.2 no.1
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• pp.17-23
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• 2007

Shot interfering RNA (siRNA) can be used to silence specific gene expression and have many potential therapeutic applications. However, how to design an effective siRNA is still not clear. Highly effective siRNA has sequence-specific properties which are low G/C content, low internal stability at the sense strand 3'-terminus, sense strand base bias(position 1 is G/C, position 19 is /AU). Recently, mRNA secondary structure playsan important role in RNAi. Target site of siRNA in high-ordered structure (i.e hairpin loop, multi loop) or base pair of many hydrogen bonds dramatically reduce function of siRNA mediated gene silencing. Possible off-target effects of siRNA is detecting from BLAST search.