• Korean Journal of Microbiology
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• v.29 no.3
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• pp.189-194
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• 1991

The degree of the genetic variations among Clostridium thermocellum ATCC 27405 and the wild type strains was investigated by the mehtod of GC ratio, DNA-DNA hybridization and RFLP (Restriction Fragment Length Polymorphism) patterns by ribosomal RNA and M13 probe. GC ratio and KNA homology values of th three isolates were approximately equal to those of ATCC type strain. The RFLP patterns by the rRNA and M13 probe showed some differences among C. thermocellum ATCC 27405, wild type strains and Clostridium thermohydrosulfuricum ATCC 33223, indicating that the two probes can be useful in subspecies- and apecies-identification.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.113.1-113.1
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• 2011

The Leo ring in the M96 group is unique in its morphology and size among the intergalactic gas features found in nearby universe. Its ring-like structure of 200 kpc on diameter appears to be orbiting around the M105-NGC 3384 pair with $1.67{\times}109\;M{\odot}$ of HI gas. While the origin of the ring - whether it is primordial or tidally stripped - is yet unclear, the optical and gas properties of dwarf galaxies associated with the gas ring help us to understand the formation process of this large scale intergalactic HI cloud. At the first step, we present the optical catalog of dwarf galaxy candidates in the Leo ring using deep optical images with MegaCam on the CFHT. Image convolution method is used in order to detect very faint dwarf galaxies. Comparing the ALFALFA HI data from the literature, we have identified that 4 dwarf candidates coexist with HI clumps. There are also 27 HI dwarfs with no optical counterpart and 12 optical dwarfs with no HI clump. In this work, we probe the optical and global gas properties of these dwarfs.

• Animal cells and systems
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• v.2 no.1
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• pp.113-116
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• 1998

A cDNA clone coding for ribosomal protein 46 (rp46) which is a component of 60S ribosomal large subunit has been identified from Drosophila melanogaster. A cDNA clone encoding S. cerevisiae rp46 was used as a probe to screen a Drosophila larvae cDNA library. The DNA sequence analysis revealed that the cDNA coding for Drosophils rp46 contains a complete reading frame of 153 nucleotides coding for 51 amino acids. The deduced amino acid sequence showed 71-75% homology with those of other eukaryotic organisms. Northern blot analysis showed that about 1-kb rp46 transcripts are abundant throughout fly development. Whole mount embryonic mRNA in situ hybridization also showed no preferential distribution of the transcripts to any specific region. The chromosomal in situ hybridization revealed that the identified gene is localized at position 60C on the right arm of the second polytene chromosome with a possibility of single copy.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.105-105
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• 2002

염색체의 구조적 이상으로 인한 습관성 유산과 기형아의 출산을 예방하기 위해 착상전 배아에서 할구를 분석하여 정상적인 핵형을 가진 배아만을 이식하는 착상전 유전자 진단 (preimplantation genetic diagnosis, PGD)의 성공적인 임상 적용이 보고되고 있으며, 그 적용 범위가 확대되고 있다. 그러나 일반적인 간기의 핵상을 이용한 PGD에서는 형광직접보합법 probe의 제약으로 보인자와 정상적인 핵형을 구분할 수 없는 단점이 있다. 따라서 본 연구에서는 보다 정확한 PGD를 위해 생쥐 배아를 이용하여 분리한 할구에서 중기 염색체상을 획득하기 위해 미세소관 (microtubule) 형성 저해제를 처리하였으며, 이를 통해 확립된 방법을 인간의 PGD에 적용하고자 하였다. 과배란이 유도된 ICR 생쥐에서 4- 또는 8-세포기 배아를 수획하여 colcemid, nocodazole, vinblastine을 각각 0.1, 0.5, 1.0, 5.0$\mu$M을 처리하고, hoechst 33342로 염색하여 핵상을 관찰하여 최적의 농도를 결정하였다. 또한 각 미세소관 형성 저해제를 혼합 처리하여 가장 높은 중기 염색체상을 획득할 수 있는 혼합 처리를 결정하였다. 이렇게 결정된 혼합 처리 방법을 인간의 체외 수정 및 배아 이식술에서 획득된 3PN 배아에 처리하여 중기 염색체를 획득하였다. Colcemid, nocodazole, vinblastine 모두 1 $\mu$M이 최적 농도임을 확인할 수 있었다 (각각 96.3%, 92.0%, 98,4%). 미세소관 형성저해제를 혼합 처리하였을 경우 nocodazole과 vinblastine (각각 1$\mu$M)을 혼합 처리했을 때 중기 염색체 획득률(97.3%)이 가장 높았다. 인간의 3PN 배아에 1$\mu$M의 nocodazole과 vinblastine을 혼합 처리한 후, 113개의 할구를 분석하여 44개(38.9%)의 할구에서 중기 염색체를 확인할 수 있었다. 본 실험 결과를 통해 중기 염색체를 획득하기 위하여 미세소관 형성 저해제를 처리하는 방법은 생쥐의 배아에서는 효과적이지만, 인간의 배아에서는 그 효율이 다소 낮음을 알 수 있었다. 그러나 이 방법을 개선하여 인간의 할구에서 중기 염색체의 획득률을 높이고, 이를 염색체의 구조적 이상에 대한 착상전 유전자 진단에 적용한다면, 보인자와 정상의 핵상을 구분하여 정상의 핵상만을 갖는 배아의 이식을 통하여 더욱 정확한 착상전 유전자 진단을 시행할 수 있으리라 사료된다.

• Journal of the Korean Magnetic Resonance Society
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• v.21 no.3
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• pp.109-113
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• 2017

The hepatitis C virus (HCV) internal ribosome entry site (IRES) is an RNA structure located in the 5'-UTR of the HCV RNA genome. The HCV IRES consists of four domains I, II, III, and IV, where domains II - IV are recognized by 40S ribosomal subunit and the domain III is bound to eukaryotic initiation factor 3 (eIF3) for translation initiation. Here, we have characterized the tertiary interaction between an L-/K- rich peptide and the HCV IRES domain IV. To probe the peptide binding interface in RNA, we synthesized $^{13}C$- and $^{15}N$-double labeled RNA and the binding site was identified by using the chemical shift perturbation (CSP) NMR methods. Our results showed that the peptide binds to the upper stem of the IRES domain IV, indicating that the tertiary interaction between the IRES domain IV and the peptide would disrupt the initiation of translation of HCV mRNA by blocking the start codon exposure. This study will provide an insight into the new peptide-based anti-viral drug design targeting HCV IRES RNA.

• Genomics & Informatics
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• v.5 no.3
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• pp.113-117
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• 2007

The development of microarray technology has facilitated the understanding of gene expression profiles. Despite its convenience, the cause of dye-bias that confounds data interpretation in dual-color DNA microarray experiments is not well known. In order to economize time and money, it is necessary to identify the cause of dye bias, since designing dye-swaps to reduce the dye-specific bias tends to be very expensive. Hence, we sought to determine the reliable cause of systematic dye bias after treating murine macrophage RAW 264.7 cells with 2-keto-3-deoxyoctonate (KDO), interferon-beta $(IFN-{\beta})$, and 8-bromoadenosine (8-BR). To find the cause of systematic dye bias from the point of view of fluorescence quenching, we examined the correlation between systematic dye bias and the proportion of each nucleotide in mRNA and oligonucleotide probe sequence. Cy3-dye bias was highly correlated with the proportion of adenines. Our results support the fact that systematic dye bias is affected by fluorescence quenching of each feature. In addition, we also found that the strength of fluorescence quenching is based on not only dye-dye interactions but also dye-nucleotide interactions as well.