• Journal of Yeungnam Medical Science
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• 제8권2호
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• pp.63-69
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• 1991

신경교종에서 핵소체 조성부를 측정하기 위해 18예의 인체 신경교종을 대상으로 은교질염색을 시행하였다. 그 결과 정상뇌의 성상세포는 $1.17{\pm}0.07$의 핵소체 조성부수를 보였고 성상세포종의 핵소체 조성부수는 $1.53{\pm}0.25$, 악성 성상세포종은 $2.37{\pm}0.71$, 다형성 신경교아종은 $2.88{\pm}0.41$이었으며 각 군들간에 유의한 차이를 보였다. 그래서 은교질 염색법에 의한 핵소체 조성부의 측정은 환자에게 부담을 주지 않는 비교적 간단하고 빠른 방법으로 신경교종의 증식능을 판정하는데 어느정도 도움이 될 것으로 생각한다.

• Journal of Microbiology and Biotechnology
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• 제27권11호
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• pp.1999-2009
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• 2017

The secretion efficiency of a protein in a Sec-type secretion system is mainly determined by an N-terminal signal peptide and its combination with its cognate protein. Five signal peptides, namely, two synthetic Sec-type and three Bacillus licheniformis alpha-amylase-derived signal peptides, were compared for periplasmic expression of the human growth hormone (hGH) in E. coli. Based on in silico predictions on the signal peptides' cleavage efficiencies and their corresponding mRNA secondary structures, a number of amino acid substitutions and silent mutations were considered in the modified signal sequences. The two synthetic signal peptides, specifically designed for hGH secretion in E. coli, differ in their N-terminal positively charged residues and hydrophobic region lengths. According to the mRNA secondary structure predictions, combinations of the protein and each of the five signal sequences could lead to different outcomes, especially when accessibility of the initiator ATG and ribosome binding sites were considered. In the experimental stage, the two synthetic signal peptides displayed complete processing and resulted in efficient secretion of the mature hGH in periplasmic regions, as was demonstrated by protein analysis. The three alpha-amylase-derived signal peptides, however, were processed partially from their precursors. Therefore, to achieve efficient secretion of a protein in a heterologous system, designing a specific signal peptide by using a combined approach of optimizations of the mRNA secondary structure and the signal peptide H-domain and cleavage site is recommended.

• 한국미생물·생명공학회지
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• 제18권3호
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• pp.309-316
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• 1990

Bacillus circulans F-2의 생산하는 NaCl 의존성 amylase(NaCl-dependent amylase) 유전자를 함유하는 1795bp의 DNA 염기배열을 결정하였다. 본 유전자의 ORF는 총염기수 1005bp(335 아미노산)로 구성되며, 분자량 38,006의 amylase의 분자량 약 35,000과 일치하였다. 본 유전자의 상류영역(upstream region)에는 고초균(Bacillus subtiis)의 전형적인 전사발현영역(transcriptional region)과 상보적인 DNA역역이 존재하였다. 성숙단백질의 N-말단측 아미노산 배열은 Ala-Ser-Lys-Val-Gly이며, 분비에 필요한 20개의 signal 아미노산 배열을 갖는 전형적인 분비 단백질임이 확인 되었다. 한편 다른 amylase들과 비교결과, smylase 활성발현과 밀접히 관련되 있는 4개 부위의 상보성영역(homologous region)을 가지고 있었다.

• 생명과학회지
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• 제21권6호
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• pp.788-795
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• 2011

병원균에 대한 정확한 동정은 임상 연구실에서 필수적인 요소의 하나이다. Chyseobacterium indologenes에 대한 동정을 포함한 분자생물학적 분석과 리보솜의 16S rRNA 유전자로 한국에서 추출한 17검체와 GenBank에서 Chyseobacterium속 검색을 통해 이들과 계통관계를 평가하였다. C. indologenes의 배당 서열은 1,176 nucleotides였다. C. indologenes 내의 서열 변이는 주로 염기 치환이었다. 한국의 C. indologenes 검체는 다른 나라의 동 종과 크게 다르지 않았다. 그런데 한국의 C. indologenes의 치환율은 GenBank에 있는 동종보다 높았다. C. indologenes는 C. isbiliense, C. hominis, C. hispanicum, C. molle, C. hungaricum, and C. pallidum과 자매종을 형성하였다.

• The Plant Pathology Journal
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• 제30권3호
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• pp.236-244
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• 2014

The plant pathogen Fusarium graminearum causes Fusarium head blight in cereal crops and produces mycotoxins that are harmful to animals and humans. For the initiation and spread of disease, asexual and sexual reproduction is required. Therefore, studies on fungal reproduction contribute to the development of new methods to control and maintain the fungal population. Screening a previously generated transcription factor mutant collection, we identified one putative $C_2H_2$ zincfinger transcription factor, pcs1, which is required for both sexual and asexual reproduction. Deleting pcs1 in F. graminearum resulted in a dramatic reduction in conidial production and a complete loss of sexual reproduction. The pathways and gene ontology of pcs1-dependent genes from microarray experiments showed that several G-protein related pathways, oxidase activity, ribosome biogenesis, and RNA binding and processing were highly enriched, suggesting that pcs1 is involved in several different biological processes. Further, overexpression of pcs1 increased conidial production and resulted in earlier maturation of ascospores compared to the wild-type strain. Additionally, the vegetative growth of the overexpression mutants was decreased in nutrient-rich conditions but was not different from the wild-type strain in nutrient-poor conditions. Overall, we discovered that the pcs1 transcription factor positively regulates both conidiation and sexual reproduction and confers nutrient condition-dependent vegetative growth.

• Applied Microscopy
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• 제27권1호
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• pp.87-100
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• 1997

To investigate the effects of mercuric chloride $(HgCl_2)$ on the differentiation of the cerebral neuron of chick embryo 10 days, the ultrastructural changes in nerve cells injected with a various doses of mercuric chloride were observed with transmission electron microscope. The enzyme activity of the some dehydrogenases, cerebral proteins and adenosine triphosphate (ATP) were also analyzed. The results obtained are as follows; The ultrastructural changes in 1.0 mg-injected group, the nuclear membranes were irregular, outer of mitochondria membrances dispressioned, their cristae were destroyed. In 2.0 mg-injected group, the nuclear envelops were destroyed and divided, were not observed organelle except of few ribosome, the RER and mitochondria. The number of polypeptide bands were separated by SDS-PAGE in the normal group were 38 bands. According to the in creased dose of mercuric chloride, contends of the bands were increased in 4 bands, but were decreased in 1 band. The activities of dehydrogenases were declined by increasing the dose of mercuric chloride. Lactate dehydrogenase (LDH) activity fatted to 61% in 2.0 mg-injected group. Malate dehydrogenase (MDH) activity fatted to 90% in 1.0 mg-injected group, greatly to 76% in 2.0 mg-injected group. Succinate dehydrogenase (SDH) activity decreased to 79% in 1.0 mg-injected group and greatly to 62% in 2.0 mg-injected group. ATP content in 1.0 mg-injected group was almost near to the normal level, but it was increased greatly in 2.0 mg-injected group.

• 한국동물학회지
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• 제38권3호
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• pp.388-394
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• 1995

동면동물인 다람쥐를 활동기와 동면기로 나누어 소장 점막 상피세포인 원주세포와 점액세포의 미세구조 변화를 투과전자현미경을 이용하여 관찰하였다. 활동기의 원주세포에서는 많은수의 미토콘드리아와 과립형질내세망을 관찰할 수 있었다. 동면기의 원주세포에서는 많은수의 리보소옴을 관찰할 수 있었다. 활동기의 점액세포에서는 크고 많은수의 점액과립과 세포소기관으로 미토콘드리아와 과립형질내세망을 관찰할 수 있었으며 현저한 분비작용을 관찰할 수 있었다. 동면기의 점액세포에서는 수와 크기에서 감소된 점액과립과 활동기보다 증가된 리보소옴을 관찰할 수 있었으며 분비작용은 활동기에 비해 감소하였다.

• Archives of Pharmacal Research
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• 제23권2호
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• pp.187-195
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• 2000

Nucleotide sequence extending 2,3-dihydroxybiphenyl 1,2-dioxygenase gene (pcbC) and 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoate hydrolase gene (pcbD) of Pseudomonas sp. DJ-12 was previously analyzed and the two genes were present in the order of pcbD-pcbC preceded by a promoter from Pseudomonas sp. DJ-12. In this study, a 3.8-kb nucleotide sequence located downstream of the pcbC gene was analyzed to have three open reading frames (ORFs) that are designated as orf1, pcbE and orf2 genes. All of the ORFs were preceded by each ribosome-binding sequence of 5-GGAXA-3 (X=G or A). However, no promoter-like sequence and transcription terminator sequence were found in the analyzed region, downstream of pcbC gene. Therefore, the gene cluster appeared to be present in the order of pcbD-pcbC-orf1-pcbE-orf2 as an operon, which is unique organization characterized so far in biphenyl- and PCB-degrading bacteria. The orf1 gene was composed of 1,224 base pairs which can encode a polypeptide of molecular weight 44,950 containing 405 amino acid residues. A deduced amino acid sequence of the orf1 gene product exhibited 21-33％ identity with those of indole dioxygenase and phenol hydroxylase components. The pcbE gene was composed of 783 base pairs encoding 2-hydroxypenta-2,4-dienoate hydratase involved in the 4-chlorobiphenyl catabolism. The orf2 gene was composed of 1,017 base pairs encoding a polypeptide of molecular weight 37,378 containing 338 amino acid residues. A deduced amino acid sequence of the orf2 gene product exhibited 31％ identity with that of a nitrilotriacetate monooxygenase component.

• 한국동물학회지
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• 제33권1호
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• pp.12-21
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• 1990

광학 현미경하에서 메기배부 피부의 멜라닌 색소포는 피부의 표면층에 수평으로 배열되어 있었으며, melanosnme으로 채워진 소수의 돌기들이 관찰되었다. 각각의 멜라닌 색소포들은 흑색 또는 어두운 갈색으로 보였다. 전자현미경에서 표피 멜라닌 색소포들은 양측면으로 크게 분지되었고 멜라닌색소포의 작은 독기들은 세포간극의 부근에서 자주 발견되었다. 멜라닌 색소포돌기의 횡단면은 거의 환상형이며, 가끔 얇은 층의 표피세포로 둘러싸여 있었다. 몇몇 돌기들은 넓은 세포간극이나 표면층 상피세포의 세포질 속에서 구분되었다. 성숙한 멜라닌 색소포에서는 mealnosome, mitochondria, free ribosome이 핵 주변부에 현저하게 발달되었고, melanosom은 구형 또는 난원형이었으며 각 melanosome은 한계막으로 둘러싸여 있었다. 성숙한 멜라닌 색소포의 돌기들은 잘 발달되었니만 미성숙한 멜라닌 색소포의 돌기들은 불완전하게 발달되었다.

• Molecules and Cells
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• 제26권1호
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• pp.26-33
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• 2008

The plasmid pJB01, a member of the pMV158 family isolated from Enterococcus faecium JC1, contains three open reading frames, copA, repB, and repC. Plasmids included in this family produce counter-transcribed RNA (ctRNA) that contributes to copy number control. The pJB01 ctRNA, a transcript which consists of 54 nucleotides (nts), is encoded on the opposite strand from the copA/repB intergenic region and partially overlaps an atypical ribosome binding site (ARBS) for repB. The ARBS is integrated by the two underlined conserved regions: 5'-TTTTTGTNNNNTAANNNNNNNNNATG-3', and the ctRNA is complementary only to the 5' conserved sequence 5'-TTTTTGT-3'. This complementary sequence is located at a distance from the terminal loop of the ctRNA secondary structure. The ctRNA structure predicted by the mfold program suggests the possible generation of a terminal and an internal hairpin loop. The amount of in vitro translation product of repB mRNA was inversely proportional to the ctRNA concentration. Mutations in the terminal and internal hairpin loops of the ctRNA had inhibitory effects on its binding to the target mRNA. We propose that the intact structures of the terminal and internal hairpin loops, respectively, play important roles in forming the initial kissing and extending complexes between the ctRNA and target mRNA and that these regulate the copy number of this plasmid.