• 한국약용작물학회지
• /
• 제28권5호
• /
• pp.325-330
• /
• 2020

Background: Dried tuberous roots of Cynanchum wilfordii are known to relieve menopause symptoms. However, the dried roots of C. wilfordii are morphologically similar to those of C. auriculatum, which makes it difficult to distinguish when used as a medicine. Various comparative studies have focused on chemical or molecular analysis of these roots. However, the differences between the two species at the cytogenetic level based on chromosome structure and composition remain to be elucidated. Methods and Results: For chromosome slides, the roots were fixed in 8-hydroxyquinoline, digested with enzyme mixture, and spread on slides. 5S and 45S rDNA were used as cytogenetic markers for the analysis of nuclear genomes by FISH. The chromosome number of the two species was 2n = 22, with a relatively short length, 1.13 ㎛ - 4.24 ㎛ and 1.00 ㎛ - 3.42 ㎛ with respect to each other. Both species represent one pair of 5S and 45S rDNA signal on chromosome 1, at the proximal region and peri-centromeric region, respectively. Conclusions: These preliminary cytogenetic data using FISH in C. wilfordii and C. auriculatum could be valuable for the comprehension of Cynanchum genome history.

• 미생물학회지
• /
• 제30권4호
• /
• pp.246-251
• /
• 1992

대두 (Glycine max) 뿌리혹의 질소고정 공생균주 Bradyrhizobium japonicum SNU001 의 nod 유전자를 클로닝하였다. Rhizobium meliloti 의 4.5 kb EcoRI/ HindIII 절편을 탐침으로 한 게놈 혼성화 반응을 분리균주의 게놈상에 nod 유전자가 존재함을 확인하고, lambda EMBL3-BamHI vector 를 이용하여 genomic library 를 작성하였다. 작성된 library 로부터 1, 2 차 선별과정을 통해 nod 유전자가 있는 클론 1-5 를 선별하고, 클론 2로부터 nod DABC 탐침과 lambda DNA 탐침을 사용한 혼성화반응을 수행하여 삽입된 genomic DNA 에 대한 부분적인 제한효소 지도를 작성하였다. nod DABC 탐침과 가장 강한 혼성화반응을 보인 phage 클론 lambda CNS-1 의 3.9 kb BamHI 절편을 pBS KS(+) vector 에 subcloning 하고 동일한 탐침을 이용한 혼성화반응을 통해 subclone pBjCNS-1 을 선별하였다. 이 subclone 에 대한 부분적인 제한효소 지도를 작성하여 nod DABC 가 1.8 KpnI/SacI 절편에 존재함을 확인하였다.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 1999년도 춘계 학술대회지
• /
• pp.162-163
• /
• 1999

The goal of this research was (1) to describe the conditions and parameters required for the cell cycle synchronization and the accumulation of large number of metaphase cells in maize and other cereal root tips, (2) to isolate intact metaphase chromosomes from root tips suitable for characterization by flow cytometry, and (3) to construct chromosome-specific libraries from maize. Plant metaphase chromosomes have been successfully synchronized and isolated from many cereal root-tips. DNA synthesis inhibitor (hydroxyurea) was used to synchronize cell cycle, follwed by treatement with trifluralin to accumulate metaphase chromosomes. Maize flow karyotypes show substantial variation among inbred lines. thish variation should be sueful in isolating individual chromosome types. In addition, flow cytometry is a useful method to measure DNA content of individual chromosomes in a genotyps, and to detect chromosomal variations. Individual chromosome peaks have been sorted from the maize hybrid B73/Mol7. Libraries were generated form the DOP-PCR amplification product from each peak. To date, we have analyzed clones from a library constructed from the maize chromosome 1 peak. Hybridization of labeled genomic DNA to clone inserts indicated that $24\%,\;18\%,\;and\;58\%$ of the clones were highly repetitive, medium repetitive, and low copy, respectively. Fifty percent of putative low cpoy clones showed single bands on inbred screening, blots, and the remaining $50\%$ were low copy repeats. Single copy clones showing polymorphism will be mapped using recombinant inbred mapping populations. Repetitive clones are being characterized by Southern blot analysis, and will be screened by in situ hybridization for their potential utility as chromosome specific markers.

• 한국균학회지
• /
• 제17권4호
• /
• pp.209-213
• /
• 1989

사철 느타리 버섯 Uracil 요구성 균주를 Aspergillus nidulans ans 1과 Neurospora crassa pyr 4 유전자를 지닌 백터를 이용하여 형질전환시켰다. 사철 느타리버섯 ura 요구성 균주의 원형질체를 pyr 4 유전자를 지닌 백터 pDJB3과 혼합 후 PEG와 $CaCl_2$를 처리하였다. 형질전환 균주는 버섯 최소배지에서 안정되게 생육하였고 southern hybridization 결과도 백터 DNA가 사철 느타리 염색체에 삽입되었다. 형질전환 균주는 단핵성이므로 다른 단핵 균사와 균사 융합 후 자실체 형태, 포자형성 등을 조사하였다. 형질전환이 안된 균주는 톱니형 자실체를 형성한데 비해 형질전환된 균주는 톱니형, 깔대기형, 우산형, 갓 미발육형의 자실체를 형성하였다.

• Journal of Gastric Cancer
• /
• 제12권2호
• /
• pp.73-80
• /
• 2012

Purpose: The specific aim of this study is to unravel a DNA copy number alterations, and to search for novel genes that are associated with the development of Korean gastric cancer. Materials and Methods: We investigated a DNA copy number changes in 23 gastric adenocarcinomas by array-comparative genomic hybridization and quantitative real-time polymerase chain reaction analyses. Besides, the expression of UQCRFS1, which shows amplification in array-CGH, was examined in 186 gastric cancer tissues by an immunohistochemistry, and in 9 gastric cancer cell lines, as well as 24 gastric cancer tissues by immunoblotting. Results: We found common gains at 48 different loci, and a common loss at 19 different loci. Amplification of UQCRFS1 gene at 19q12 was found in 5 (21.7%) of the 23 gastric cancers in an array-comparative genomic hybridization and DNA copy number were increased in 5 (20.0%) out of the 25 gastric cancer in quantitative real-time polymerase chain reaction. In immunohistochemistry, the overexpression of the protein was detected in 105 (56.5%) out of the 186 gastric cancer tissues. Statistically, there was no significant relationship between the overexpression of UQCRFS1 and clinicopathologic parameters (P>0.05). In parallel, the overexpression of UQCRFS1 protein was confirmed in 6 (66.7%) of the 9 gastric cancer cell lines, and 12 (50.0%) of the 24 gastric cancer tissues by immunoblotting. Conclusions: These results suggest that the overexpression of UQCRFS1 gene may contribute to the development and/or progression of gastric cancer, and further supported that mitochondrial change may serve as a potential cancer biomarker.

• Molecules and Cells
• /
• 제23권3호
• /
• pp.280-286
• /
• 2007

L-asparaginase (EC 3.5.1.1) catalyzes the hydrolysis of the amide group of L-asparagine, releasing aspartate and $NH_4{^+}$. We isolated a low temperature-inducible cDNA sequence encoding L-asparaginase from soybean leaves. The full-length L-asparaginase cDNA, designated GmASP1, contains an open reading frame of 1,258 bp coding for a protein of 326 amino acids. Genomic DNA blotting and fluorescence in situ hybridization showed that the soybean genome has two copies of GmASP1. GmASP1 mRNA was induced by low temperature, ABA and NaCl, but not by heat shock or drought stress. E. coli cells expressing recombinant GmASP1 had 3-fold increased L-asparaginase activity. A possible function of L-asparaginase in the early response to low temperature stress is discussed.

• 식물분류학회지
• /
• 제49권2호
• /
• pp.127-139
• /
• 2019

The purported four hybrid origins of Asplenium in Korea were tested based on morphological, cytological and DNA sequence data. Asplenium castaneo-viride, A. ${\times}$ uiryeongse, A. ${\times}$ montanus, and A. ${\times}$ kitazawae share several morphological characteristics with the Asian walking fern A. ruprechtii and related taxa as parents and show a sympatric distribution with the putative parents, raising the possibility of hybrid origins: A. castaneo-viride (A. ruprechtii and A. incisum), A. ${\times}$ uiryeongse (A. ruprechtii and A. pekinense), A. ${\times}$ montanus (A. ruprechtii, A. trichomanes, and A. incisum), and A. ${\times}$ kitazawae (A. ruprechtii and A. sarelii). We investigated flow cytometry and chloroplast DNA sequence data (rbcL, rps4-trnS, and rps4-trnS intergenic spacer) to clarify the hybridization and origin of each hybrid. In the flow cytometry analyses, A. ruprechtii shows diploid (2x) only, whereas A. castaneo-viride (3x, 4x), A. ${\times}$ uiryeongse (3x), A. ${\times}$ montanus (3x, 4x), and A. ${\times}$ kitazawae (2x, 4x) exhibit polyploidy, suggesting hybrid events along speciation. The rbcL and rps4-trnS and rps4-trnS intergenic spacer data suggest that A. ruprechtii is one the maternal ancestors of all four hybrids. In addition, the rps4-trnS and rps4-trnS intergenic spacer data indicate that A. incisum is also the maternal ancestor of A. ${\times}$ kitazawae and A. ${\times}$ montanus, proposing multiple hybridization events for these two hybrids. In A. ${\times}$ montanus, morphological features such as the leaf forms and sympatric distributions of the species also support the multimaternal hypothesis, but the morphological features of A. ${\times}$ kitazawae must be examined with consideration of hybrid events. To clarify the complex hybrid evolutionary lineages of the four Asplenium hybrids, further research with taxon sampling and molecular markers should be conducted.

• 미생물학회지
• /
• 제32권1호
• /
• pp.47-52
• /
• 1994

Campylobacter jejuni에 48${\circ}C$의 열충격을 30분간 주었을 때, HSP90, HSP66, HSP60의 열충격 단백질들이 합성되었고, 이 단백질들은 각각 E. coli의 hsp87, HSP66 (DnaK), HSP58(GroEL)에 상응하는 단백질들이었다. 여러가지의 제한효소로 처리한 C. jejuni의 chromosomal DNA에 E. coli의 groEL(4.0kb)을 probe로 사용하여 Southern hybridization한 결과, 이들과 상동성을 가지는 유전자들이 있음을 확인하였다. C. jejuni의 groEL 유전자를 pWE15 cosmid를 이용하여 recombinant plasmid pLC1을 만들고, 이를 E. coli B178 groEL44 ts mutant에 형질전환시켜 E. coli LC1을 얻었다. 이 pLC1에는 groEL 유전자가 존재하는 5.7kb인 insert DNA가 포함되어 있었고, 그로부터 subcloning한 pLC101에는 groEL을 포함하는 4.0kb의 DNA가 삽입되어 있었다. 이 recombinant plasmid들이 형질전환된 E. coli LC1과 LC101 균주에서는 C. jejuni의 GroEL 단백질이 과다 생산되었다. C. jejuni의 groEL이 cloning된 E. coli LC1은 42${\circ}C$에서의 생장능력이 회복되었고, ${\lambda}$ vir phage에 대한 감수성도 회복되는 등의 chaperon 효과가 입증되었다.

• Journal of Microbiology and Biotechnology
• /
• 제10권3호
• /
• pp.312-320
• /
• 2000

Abstract The full sequence of the plasmid pKJ36, which was derived from Bifidobacterium longum KJ, was determined and analyzed to construct shuttle vectors between E. coli and Bifidobacterium. The plasmid pKJ36 was composed of 3,625 base pairs with a 65.1% G+C content. The structural organization of pKJ36 was highly similar to that of pKJ50, and the three major ORFs on pKJ36 showed high amino acid sequence homologies with those of pKJ50. The putative proteins coded by these three ORFs were designated as RepB (32.0 kDa, pI=9.25), MembB (29.0 kDa, pI=12.25), and MobB (39.0 kDa, pI=IO.66), respectively. The amino acid sequence of RepB showed a 57% identity and 70% similarity with that of the RepA protein of pKJ50. Upstream of the repB gene, the so-called iteron sequence was directly repeated four-and-ahalf times and a conserved dnaA box was identified. An amino acid sequence comparison between the MobB and MobA of pKJ50 revealed a 48% identity and 61 % similarity. A conserved oriT sequence with an inverted repeat identical to that of pKJ50 was also found upstream of the mobB gene. A hydropathy analysis of MembB revealed four possible transmembrane regions. The expressions of the repB and membB genes were confirmed by RT-PCR. The in vitro translation reaction of pKJ36 showed protein bands with anticipated sizes with respect to each putative gene product. S 1 endonuclease treatment and Southern hybridization suggested that pKJ36 replicates by a rolling circle mechanism via a single-stranded DNA (ssDNA) intermediate. A shuttle vector between E. coli and Bifidobacterium sp. was constructed using the pKJ36, pBR322, and staphylococcal chloramphenicol acetyl transferase (CAT) gene. The successful transformation of the Bifidobacterium strains was shown by Southern hybridization and PCR. The transformation efficiency differed from strain to strain and, depending on the electroporation conditions, with a range between $1.2{\times}10^1-2.6{\times}10^2{\;}cfu/\mu\textrm{g}$ DNA.X> DNA.

• 한국미생물·생명공학회지
• /
• 제44권4호
• /
• pp.512-521
• /
• 2016

제주도에서 채집된 토양시료로부터 xylanase 활성을 나타내는 균주를 분리하여 WJ-2로 명명하였다. 균주 WJ-2의 16S rRNA 유전자 염기서열을 결정하여 이를 토대로 상동성을 검색한 결과, Streptomyces 속의 균주들과 높은 염기서열 상동성을 보였다. 16S rRNA 유전자 염기서열을 토대로하는 neighbor-joining 계통수를 제작하여 Streptomyces atrovirens와 가장 높은 계통발생적 연관성이 갖고 있는 것을 밝혔다. 또한 DNA-DNA hybridization 분석을 통하여 Streptomyces atrovirens의 신규한 아종임을 증명하였다. 균주 WJ-의 게놈내 GC 농도는 73.98 mol%이었으며, 주요 세포벽 지방산으로 anteiso-$C_{15:0}$ (36.19%)을 함유하고 있었다. 균주 WJ-2의 성장 및 xylanase 생산은 배지내에 질소원으로 soytone과 탄소원으로 xylan을 첨가하였을 때 급격히 증가되는 것을 확인하였다. 액체배양액으로부터 준비된 조효소의 xylanase 활성은 pH 7.0과 $55^{\circ}C$에서 가장 높게 나타났다. Thin layer chromatography (TLC) 분석을 통하여 균주 WJ-2의 조효소는 xylan을 분해하여 최종분해산물로서 xylobiose와 xylotriose 생산하는 효소임을 확인하였다.