• Research in Plant Disease
• /
• v.26 no.3
• /
• pp.179-182
• /
• 2020

In July 2018, a serious rust symptom was found throughout the fringe trees planted in Gangjin-gun, Korea. Yellow and brown spots were observed on the adaxial (topside) surface of the collected fringe tree leaves, and yellow color aecia were observed on the abaxial (underside) surface leaves. The size of aeciospore and urediniospores of JCK-KCFR1 strain were measured to 41.2 ㎛ (Φ) and 28.84 ㎛ (Φ) with a light microscope. Phylogenetic analysis of the small subunit rRNA, internal transcribed spacer, and large subunit rRNA region indicated that JCK-KCFR1 strain is novel species of the genus Puccinia and closely related to Puccinia kusanoi, which has been reported a rust pathogen on bamboo. In May 2019, rust symptoms were also discovered on the bamboo leaves planted around the fringe tree on Muwisa-ro, and their telia and teliospores were observed on the abaxial leaf surfaces of the bamboo with 100% sequence homology with the rust of the fringe tree. This is the first report that Puccinia sp. JCK-KCFR1 is a new species that requires both primary (fringe tree) and alternative (bamboo) host plants to complete its life cycle in Korea.

• Korean Journal of Microbiology
• /
• v.13 no.3
• /
• pp.123-137
• /
• 1975

Sexual reproduction of paramecia have been accomplished through conjugation between individuals which have opposite mating type substances on their cilia when they were starved. Using selfing clone in which mating takes place, I examined whether a mating type change in indicidual cells required new protein and new mRNA synthesis or not and also shether there is a precursor relationship between both of the complementary mating type substances in their synthetic pathway. I found that 1. Mating type change needs new protein(s) and new mRNA synthesis. 2. Mating type substances are synthesized sequentially from mating type XIII to XIV 3. There might be a common precursor pool from which the mating type XIII substnace is synthesized and then complementary mating type XIV is fromed by addition of small group to the mating type XIII substance.

• ALGAE
• /
• v.32 no.3
• /
• pp.181-187
• /
• 2017

During a sampling at Nokdong harbor, southern coast of Korea in January 2017, the marine diatom Coscinodiscus wailesii cells infected by a novel parasitoid nanoflagellate were observed. While the development process of the trophosomes of the parasitoid was more similar to that of Pseudopirsonia mucosa, division pattern of the auxosomes was similar to that of Pirsonia species. Phylogenetic analyses inferred from 18S rRNA gene sequences revealed that the parasitoid infecting C. wailesii fell within the cercozoan groups and branched as a sister lineage of the clade consisting of Pseudopirsonia mucosa and the undescribed Cercomonas sp. SIC7235, with the sequence dissimilarity of 7.3% with Pseudopirsonia mucosa. All of these developmental and molecular characteristics suggest that the parasitoid nanoflagellate infecting the diatom C. wailesii is a new Pseudopirsonia species.

• Korean Journal of Plant Taxonomy
• /
• v.52 no.4
• /
• pp.262-268
• /
• 2022

The complete chloroplast genome (cp genome) sequence of Clematis calcicola J. S. Kim (Ranunculaceae) is 159,655 bp in length. It consists of large (79,451 bp) and small (18,126 bp) single-copy regions and a pair of identical inverted repeats (31,039 bp). The genome contains 92 protein-coding genes, 36 transfer RNA genes, eight ribosomal RNA genes, and two pseudogenes. A phylogenetic analysis based on the cp genome of 19 taxa showed high similarity between our cp genome and data published for C. calcicola, which is recognized as a species endemic to the Korean Peninsula. The complete cp genome sequence of C. calcicola reported here provides important information for future phylogenetic and evolutionary studies of Ranunculaceae.

• Parasites, Hosts and Diseases
• /
• v.53 no.1
• /
• pp.113-117
• /
• 2015

Cryptosporidium spp., ubiquitous enteric parasitic protozoa of vertebrates, recently emerged as an important cause of economic loss and zoonosis. The present study aimed to determine the distribution and species of Cryptosporidium in post-weaned and adult pigs in Shaanxi province, northwestern China. A total of 1,337 fresh fecal samples of post-weaned and adult pigs were collected by sterile disposable gloves from 8 areas of Shaanxi province. The samples were examined by Sheather's sugar flotation technique and microscopy at${\times}400$ magnification for Cryptosporidium infection, and the species in positive samples was further identified by PCR amplification of the small subunit (SSU) rRNA gene. A total of 44 fecal samples were successfully amplified by the nested PCR of the partial SSU rRNA, with overall prevalence of 3.3%. The average prevalence of Cryptosporidium infection in each pig farms ranged from 0 to 14.4%. Species identification by sequencing of SSU rRNA gene revealed that 42 (3.1%) samples were Cryptosporidium suis and 2 (0.15%) were Cryptosporidium scrofarum. C. suis had the highest prevalence (7.5%) in growers and the lowest in breeding pigs (0.97%). C. suis was the predominant species in pre-weaned and adult pigs, while C. scrofarum infected pigs older than 3 months only. A season-related difference of C. suis was observed in this study, with the highest prevalence in autumn (5.5%) and the lowest (1.7%) in winter. The present study provided basic information for control of Cryptosporidium infection in pigs and assessment of zoonotic transmission of pigs in Shaanxi province, China.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.14
• /
• pp.5667-5672
• /
• 2014

Folate receptor alpha ($FR{\alpha}$) mediates folate uptake by endocytosis, and while folate is essential to DNA methylation and synthesis and may have an important role in proliferating cells. $FR{\alpha}$ is known to be expressed in rapidly proliferating cells, including many cancer cell lines, but there has been no systematic assessment of expression in cervical cancer cell lines. The aim of the present study was to evaluate the effects of $FR{\alpha}$ on proliferation and apoptosis of cervical cells and correlation mechanism. In this study, we investigated the biological function of $FR{\alpha}$ in Hela cells using RNA interference. Cell proliferation was evaluated by Cell Counting Kit-8 (CCK8) assay, while cell cycling and apoptosis were assessed by flow cytometry, mRNA levels by real time-PCR and protein levels of $FR{\alpha}$, c-Fos and c-Jun by Western blotting. The results revealed that $FR{\alpha}$ was highly expressed in Hela cells and its silencing with a small interfering RNA (siRNA) inhibited cell proliferation and induced cell apoptosis, arresting the cell cycle in G0/G1 stages while decreasing the proportion in S and G2/M stages, and suppressed the expression levels of c-Fos and c-Jun. In conclusion, the results of this study indicated that $FR{\alpha}$ down-regulation might be capable of suppressing cervical cancer cell proliferation and promoting apoptosis. It suggested that $FR{\alpha}$ might be a novel therapeutic target for cervical cancer.

• The Korean Journal of Physiology and Pharmacology
• /
• v.4 no.2
• /
• pp.129-135
• /
• 2000

Previously, we have reported that ${\rho}-chlorophenylalanine$ (PCPA), a serotonin depletor, profoundly increased pancreatic fluid and bicarbonate secretion but remarkably inhibited pancreatic amylase secretion in anesthetized rats. The present study was performed to verify the detailed effects of PCPA on pancreatic amylase synthesis that is directly related to amylase exocrine secretion. PCPA significantly decreased pancreatic RNA and protein contents as well as the amylase activity. However, pancreatic DNA content, trypsin and chymotrypsin activities were not influenced by the treatment of PCPA. The rate of pancreatic amylase synthesis, which was assessed by the amount of incorporated $[^{35}S]-methionine$ into amylase for 1 h, was also significantly decreased by 44% in PCPA-treated rats. In order to determine whether the PCPA-induced decrease of amylase synthesis resulted from change in the level of amylase mRNA, Northern blot analysis was performed. The mRNA expression level of amylase was also decreased by 48% in the PCPA-treated rats, indicating that the inhibitory effect of PCPA on the synthesis of pancreatic amylase was mainly regulated at a step prior to translation. It was also revealed in SDS-polyacrylamide gel electrophoresis that the qualitative change of amylase was induced by PCPA. The 54 KDa amylase band seems to be degraded into small molecular weight protein bands in PCPA-treated rats, suggesting that the PCPA- induced decrease of amylase may be partly attributed to the degradation of synthesized amylase.

• Journal of Microbiology
• /
• v.34 no.1
• /
• pp.37-37
• /
• 1996

The internal regions of nuclear small subunit rRNA from 6 plaeurotus species and 5 Pleurotus ostreatus strains were amplified by PCR and sequenced. The DNA sequences of 8 Pleurotus strains (P. ostreatus NFFA2, NFFA4501, NFFA4001, KFFA4001, KFCC11635, P florida, P. florida, P. sajor-cuju, P. pulmonarius, and P. spodoleucus) were idential, but P. cornucopiae differed from them in two bases out of 605 bases. However, p[hylogenetic analysis of the sequences by DNA-distance matrix and UPGMA methods showed that P. ostreatus NFFA2m1 and NFFA2m2, known as mutants of P. ostreatus NFFA2, belonged to anther group of Basidiomycotina, which is close to the genus Auricularia. The difference of the SSU rDNA sequences of P. cornucopiae from other Pleurotus species tested corresponds to the difference of mitochondrial plasmid type present in Pleurotus species as observed by Kim et al. (1993, Korean J. Microbiol. 31, 141-147).ishement of silencing at the HMR/hsp82 locus can occur in G1-arrested cells. Cell cycle arrest at G1 phase was achieved by treatment of early log a cell cultures with .alpha.-factor mating pheromone, which induces G1 arrest. The result suggests that passage through S phase (and therefore DNA replication) is nor required for re-establishing silencer-mediated repression at the HMNRa/HSP82 locus. Finally, to test whether de nono protein synthesis is required for re-establishment of silencer-mediated repression, cells were pretreated with cycloheximide (500 /.mu.g/ml) 120 min. It was apparent that inhibiting protein synthesis delays, but does not prevent, re-establishment of silencer-mediated repression. Altogether, these results indicate that re-establishment of silencer-mediated repression is not dependent on the DNA replication and has no requirement for protein synthesis.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2020.12a
• /
• pp.55-55
• /
• 2020

뫼제비꽃(Viola selkirkii)의 엽록체 DNA 염기서열을 차세대염기서열분석법(NGS)을 이용하여 분석하였다. 재료는 강원도 화천군 일산과 제주도 한라산의 2개체를 사용하였다. 분석결과, 염기서열의 길이는 일산의 뫼제비꽃이 156,774 bp (GC content: 36.30%), 한라산의 뫼제비꽃이 157,451 bp(GC content: 36.30%)로 한라산 개체가 길게 분석되었다. 구간별로 LSC(Large single copy)지역은 한라산 개체(85,950 bp)가 일산 개체(85,930 bp)보다 20 bp 길었으며, SSC(Small single copy)지역은 한라산 개체(17,261 bp)보다 일산 개체가 17,982 bp로 길게 분석되었다. IR(Inverted repeat)지역은 한라산 개체가 27,120 bp로 일산 개체(26,431 bp)보다 길게 분석되었다. 이러한 염기서열 길이의 차이는 종내 개체 간 빈번하게 발생하는 현상으로 IGS와 intron 구간에서 확인 된 단순반복서열의 일부 누락과 IR지역 내의 수축과 확장에 의한 것으로 판단된다. 뫼제비꽃 2개체의 엽록체 게놈을 구성하는 유전자 수는 총 111개로 동일하였으며, protein coding gene 77개, tRNA(transfer RNA) gene 30개, 그리고 rRNA (ribosomal RNA) gene 4개로 구성되어 있었다. 이는 기 발표된 엽록체 DNA 전체 염기서열이 밝혀진 제비꽃속 (Viola) 종류들과 동일한 결과이다.

• Korean Journal of Microbiology
• /
• v.43 no.3
• /
• pp.166-172
• /
• 2007

ERM proteins transfer the methyl group to $A_{2058}$ in 23S rRNA, which reduces the affinity of MLS (macrolide-lincosamide-streptogramin B) antibiotics to 23S rRNA, thereby confer the antibiotic resistance on micro-organisms ranging from antibiotic producers to pathogens and are classified into monomethyltransferase and dimethyltransferase. To investigate the differences between mono- and dimethyltransferase, tirD, a representative monomethylase gene was cloned in Escherichia coli from Streptomyces fradiae which contains ermSF, dimethylase gene as well to overexpress the TlrD for the first time. T7 promoter driven expression system successfully overexpress tlrD as a insoluble aggregate at $37^{\circ}C$ accumulating to around 55% of the total cell protein but unlike ErmSF, culturing at temperature as low as $18^{\circ}C$ did not make insoluble aggregate of protein into soluble protein. Coexpression of Thioredoxin and GroESL, chaperone was not helpful in turning into soluble protein either as in case of ErmSF. These results might suggest that differences between mono- and dimethylase could be investigated on the basis of the characteristics of protein structure. However, a very small amount of soluble protein which could not be detected by SDS-PAGE conferred antibiotic resistance on E. coli as in ErmSF which was expected from the activity exerted by monmethylase in a cell.