• Clinical and Experimental Pediatrics
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• 제55권10호
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• pp.397-402
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• 2012

Pelizaeus-Merzbacher disease (PMD) is a rare, X-linked recessive disorder characterized by dysmyelination in the central nervous system. PMD results from deletion, mutation, or duplication of the proteolipid protein gene (PLP1) located at Xq22, leading to the failure of axon myelination by oligodendrocytes in the central nervous system. PMD may be suspected when there are clinical manifestations such as nystagmus, developmental delays, and spasticity, and genetic analysis can confirm the diagnosis. Further diagnostic manifestations of the disease include a lack of myelination on brain magnetic resonance (MR) imaging and aberrant N-acetyl aspartate (NAA) and choline concentrations that reflect axonal and myelination abnormalities on phroton MR spectroscopy. We report 5 cases of PMD (in 1 girl and 4 boys). PLP1 duplication was detected in 2 patients. Brain MR analyses and MR spectroscopy were performed for all the patients. The brain MR images showed white matter abnormalities typical of PMD, and the MR spectroscopic images showed diverse patterns of NAA, creatinine, and choline concentrations. We propose that MR spectroscopic analysis of metabolic alterations can aid the PMD diagnosis and can contribute to a better understanding of the pathogenesis of the disease.

• Journal of Microbiology and Biotechnology
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• 제27권2호
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• pp.251-261
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• 2017

Initially, we screened 18 Aspergillus sojae-like strains from Aspergillus spp. isolated from meju (Korean traditional fermented soybean brick) according to their morphological characteristics. Because members of Aspergillus section Flavi are often incorrectly identified because of their phylogenetic similarity, we re-identified these strains at the morphological and molecular genetic levels. Fourteen strains were finally identified as A. sojae. The isolates produced protease and ${\alpha}-amylase$ with ranges of 2.66-10.64 and 21.53-106.73 unit/g-initial dry substrate (U/g-IDS), respectively, which were equivalent to those of the koji (starter mold) strains employed to produce Japanese soy sauce. Among the isolates and Japanese koji strains, strains SMF 127 and SMF 131 had the highest leucine aminopeptidase (LAP) activities at 6.00 and 6.06 U/g-IDS, respectively. LAP plays an important role in flavor development because of the production of low-molecular-weight peptides that affect the taste and decrease bitterness. SMF 127 and SMF 131 appeared to be non-aflatoxigenic because of a termination point mutation in aflR and the lack of the polyketide synthase gene found in other A. sojae strains. In addition, SMF 127 and SMF 131 were not cyclopiazonic acid (CPA) producers because of the deletion of maoA, dmaT, and pks/nrps, which are involved in CPA biosynthesis. Therefore, A. sojae strains such as SMF 127 and SMF 131, which have high protease and LAP activities and are free of safety issues, can be considered good starters for soybean fermentations, such as in the production of the Korean fermented soybean products meju, doenjang, and ganjang.

• Molecules and Cells
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• 제38권8호
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• pp.723-728
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• 2015

Smurf2, a member of the HECT domain E3 ligase family, is well known for its role as a negative regulator of TGF-${\beta}$ signaling by targeting Smads and TGF-${\beta}$ receptor. However, the regulatory mechanism of Smurf2 has not been elucidated. Arginine methylation is a type of post-translational modification that produces monomethylated or dimethylated arginine residues. In this report, we demonstrated methylation of Smurf2 by PRMT1. In vitro methylation assay showed that Smurf2, not Smurf1, was methylated by PRMT1. Among the type I PRMT family, only PRMT1 showed activity for Smurf2. Transiently expressed Smurf2 was methylated by PRMT1, indicating Smurf2 is a novel substrate of PRMT1. Using deletion constructs, methylation sites were shown to be located within amino acid region 224-298 of Smurf2. In vitro methylation assay following point mutation of putative methylation sites confirmed the presence of Arg232, Arg234, Arg237, and Arg239. Knockdown of PRMT1 resulted in increased Smurf2 expression as well as inhibition of TGF-${\beta}$-mediated reporter activity. Although it is unclear whether or not increased Smurf2 expression can be directly attributed to lack of methylation of arginine residues, our results suggest that methylation by PRMT1 may regulate Smurf2 stability and control TGF-${\beta}$ signaling.

• Journal of Genetic Medicine
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• 제11권2호
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• pp.79-82
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• 2014

Mowat-Wilson syndrome is an extremely rare genetic disease that is characterized by intellectual disability, facial dysmorphism, Hirschsprung's disease, and other congenital anomalies. This disorder is caused by heterozygous mutations or deletions in the zinc finger E-box-binding homeobox-2 gene (ZEB2). Thus far, approximately 200 cases of Mowat-Wilson syndrome have been reported worldwide. In Korea, only one case with a 2q22 deletion, which also affects ZEB2, has been previously reported. Here, we describe a patient with Mowat-Wilson syndrome who presented with developmental delays, typical facial dysmorphism, and Hirschsprung's disease. Molecular analysis of ZEB2 identified a novel heterozygous mutation at c.190dup ($p.S64Kfs^*6$). To our knowledge, this is the second report of a Korean patient with Mowat-Wilson syndrome that has been confirmed genetically.

• The Plant Pathology Journal
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• 제34권6호
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• pp.470-479
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• 2018

The rice blast pathogen Magnaporthe oryzae is a global threat to rice production. Here we characterized RHO2 gene (MGG_02457) that belongs to the Rho GTPase family, using a deletion mutant. This mutant ${\Delta}Morho2$ exhibited no defects in conidiation and germination but developed only 6% of appressoria in response to a hydrophobic surface when compared to the wild-type progenitor. This result indicates that MoRHO2 plays a role in appressorium development. Furthermore, exogenous cAMP treatment on the mutant led to appressoria that exhibited abnormal morphology on both hydrophobic and hydrophilic surfaces. These outcomes suggested the involvement of MoRHO2 in cAMP-mediated appressorium development. ${\Delta}Morho2$ mutation also delayed the development of appressorium-like structures (ALS) at hyphal tips on hydrophobic surface, which were also abnormally shaped. These results suggested that MoRHO2 is involved in morphological development of appressoria and ALS from conidia and hyphae, respectively. As expected, ${\Delta}Morho2$ mutant was defective in plant penetration, but was still able to cause lesions, albeit at a reduced rate on wounded plants. These results implied that MoRHO2 plays a role in M. oryzae virulence as well.

• Journal of Genetic Medicine
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• 제18권1호
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• pp.48-54
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• 2021

Genetic imbalances are a major cause of congenital and developmental abnormalities. We report the first case of a 3p26 microdeletion and 5q35.2q35.3 microduplication in a newborn with multiple congenital anomalies evaluated using chromosomal microarray analysis (CMA) and fluorescence in situ hybridization (FISH). The patient was born at 30 weeks and 2 days of gestation with a body weight of 890 g. He had symmetric intrauterine growth restriction, microcephaly, facial dysmorphism (hypertelorism, blepharophimosis, mild low-set ears, high-arched palate, and micrognathia), and right thumb polydactyly. Echocardiography revealed an atrial septal defect and patent ductus arteriosus. Furthermore, CMA revealed a concurrent microdeletion in 3p26 and a microduplication in 5q35.2q35.3. FISH analysis showed that these genetic changes resulted from a translocation mutation between chromosomes 3 and 5. The patient's mother had mild intellectual disability, short stature, and facial dysmorphism, while his father had a normal phenotype. However, parental FISH analysis revealed that the asymptomatic father carried a balanced translocation of chromosomes 3p26 and 5q35. CMA and FISH tests are useful for diagnosing neonates with multiple congenital abnormalities. Further parental genetic investigation and proper genetic counseling are necessary in cases of chromosomal abnormalities inherited from parental balanced translocations.

• 한국작물학회지
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• 제68권4호
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• pp.294-303
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• 2023

Lipoxygenase gives soybeans their grassy flavor, which can disrupt food processing efficiency. This study aimed to identify soybean genotypes with lipoxygenase deficiency among 1,001 soybean accessions and to develop kompetitive allele specific PCR (KASP) markers that can detect lipoxygenase mutations. Three lipoxygenase isozymes (Lox1, Lox2, and Lox3) were analyzed using a colorimetric assay based on a substrate-enzyme reaction. Among the 1,001 accessions examined, two (IT160160 and IT276392) exhibited a deficiency solely in Lox1, and one (IT269984) lacked both Lox1 and Lox2. IT160160 had a 74-bp deletion in exon 8 of Lox1 (Glyma13g347600), whereas IT276392 displayed a missense mutation involving the change of C to A at position 2,880 of Lox1. Moreover, we successfully developed four KASP markers that specifically target Lox1, Lox2, and Lox3 mutations. To validate the Lox1 KASP markers, we used two F_2:3 populations generated through a cross between Daepung 2 (lipoxygenase wild type, maternal parent), IT160160, and IT276392 (null Lox1, paternal parent). The results revealed that the Daepung 2 × IT160160 group followed the expected 3:1 ratio according to Mendel's law, whereas the Daepung 2 × IT276392 group did not. Furthermore, a comparison between the colorimetric and KASP marker analyses results revealed a high agreement rate of 96%. KASP markers offer a distinct advantage by allowing the distinction of heterozygous types independent of other variables. As a result, we present an opportunity to expedite the lipoxygenase-deficient cultivar development.

• Tuberculosis and Respiratory Diseases
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• 제48권2호
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• pp.155-165
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• 2000

연구배경: Nramp1 단백은 NRAMP1 유전자에 의하여 합성되며, 이 유전자의 다형성은 결핵균에 대한 숙주의 선천적 내성을 감소시킨다. 본 연구에서는 일차 감염에 의한 결핵성 흉막염 환자에서 NRAMP1 유전자 다형성과 결핵의 일차 감염과의 관계를 고찰하였다. 방 법: 특별한 병력 없이 흉막 조직 검사를 통해 진단된 56명의 결핵성 흉막염군과 건강한 45명의 건강 대조군을 대상으로 인트론 4의 G/C 접돌연변이(469+14G/C, INT4), 543번 코돈의 aspartic acid(Asp)에서 asparagine(Asn)으로의 변이(D543N), 및 3' 비해독 영역의 TGTG 결손(1729+55del4, 3'UTR) 등의 NRAMP1 유전자 다형성의 반도를 중합효소 연쇄반응기법(PCR)과 중합효소 연쇄반응-제한효소 절단 길이 다형성(PCR-RFLP)을 이용하여 조사하였다. 결 과: 흉막염군과 건강 대조군에서의 NRAMP1 유전자 다형성의 빈도는, INT4 와 3'UTR 다형성의 경우 흉막염군에서 변이형의 빈도가 유의하게 높았으나(p=0.001, p=0.023), D543N 의 경우는 양군에서 유의한 차이가 없었다(p=0.079). 야생형과 변이형 유전자형의 교차비(odds ratio)는, INT4, 3'UTR의 경우 흉막염 환자가 변이형의 유전자형일 확률이 건강 대조군에 비해 통계적으로 유의하게 높았으나, D543N의 경우는 유의하지 않았다. INT4와 3'UTR의 결합 분석(combined analysis) 결과, 흉막염 환자가 INT4C 대립 형질을 포함할 확률과 INT4 C 대립 형질과 3'UTR del 대립 형질을 모두 포함할 확률이 통계적으로 유의하게 높았다. 결 론: 결핵성 흉막염 환자에서, 결핵 이환과 NRAMP1 유전자 다형성 중 INT4와 3'UTR과는 유의한 상관 관계가 있었으나, D543N과는 유의성이 없었으며, 흉막염 환자가 변이형 유전자형일 확률도 INT4 및 3'UTR의 경우 통계적으로 유의하게 높았으나. D543N의 경우는 높지 않았다. INT4와 3'UTR의 결합 분석결과 흉막염 환자가 INT4 C 대립 형질용 포함할 확률과 INT4 C와 3'UTR del 대립 형질을 모두 포함할 확률이 통계적으로 유의하게 높았다.

• 한국어병학회지
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• 제6권2호
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• pp.93-101
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• 1993

효모의 RNAI유전자는 RNA processing에 관여 하는지 혹은 RNA transport에 관여 하는지 아직까지 유전자의 기능이 정확히 알려져 있지 않은 실정이다. 효모의 RNAI 유전자의 기능을 파악하기 위한 방법으로 본 연구에서는 rna1-1 mutant gene을 cloning하여 이에 대한 DNA sequence를 조사함으로써 RNAI 유전자와 rna1-1 유전자의 차이점을 이해하고자 하였다. rna1-1 marker를 갖는 yeast strain(R49)로 부터 genomic DNA를 추출하여 이를 BglII로 절단하여 genomic southern blotting을 행한 결과 wild type의 경우와 동일하게 3.4 kb에서 hybridization되는 signal을 얻었으며, RNAl 및 rna1-1이 yeast genome내에 single site로 존재함을 보여 주는 결과를 얻었다. mutant strain으로 부터 얻은 3.4 kb의 BglI fragment를 pUC19의 BamHI site에 subcloning하여 transformant들을 얻었고, wild type RNAl 유전자를 probe로 하여 rna1-1 mutant 유전자를 cloning할 수 있었다. pUC19에 cloning된 RNA1유전자 및 rna1-1유전자로부터 다양한 Ba131유도체를 얻어 이들에 대한 염기 서열을 비교한 결과 transcription initation site에서부터 down stream쪽으로 17 아미노산위치에 TCC가 TTC로 대치되어 있었으며 그 결과 serine이 phenylalanine으로 변환되는 결과를 얻었다. Wild type RNAI gene의 5'-region에는 3군데의 TATA-like sequence가 true TATA box인지 확인하기 위하여 Bal3I deletion에 의해 -103nt까지 deletion된 유도체를 얻었으며 ${\Delta}RNAI$, rna1-1, 81-2-6 clone이 rna1-1 allele와 complementation한지 확인하였으나 ${\Delta}RNAI$은 TS-complementation을 하지 못하였다. 따라서 현재까지 TATA-box라고 알려진 부분은 promoter로 작용하지 못함을 확인하였다.

• 생명과학회지
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• 제16권1호
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• pp.131-135
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• 2006

미생물이 이용할 수 있는 nitrogen source는 di-, tri-, oli- go-peptide 또는 amino acid의 형태로 세포내로 uptake되어 대사과정에 사용되고 있다. 이와같은 peptide는 특이한 transport system에 의해서 이동되고 있는데 oligo peptide(Opp) transport system에는 binding protein, permease protein, energy 생성을 위한 ATP 분해에 관여하는 protein 이 관여하고 있으며 염색체 상에서 이들 단백질들은 operon 형태의 유전자로부터 발현되고 있다. 본 연구는 gram 음성 세균이며 수해양 서식 세균인 V, fluvialis로부터 얻어진 Opp operon 유전자 가운데 oligopeptide binding protein을 coding하고 있는 oppA 유전자가 deletion된 mutant를 사용하여 여러 환경변화에 따른 생육을 wild type과 비교한 연구 결과 이다. 생육을 위한 완전배지인 brain heart infusion (BHI) 배지와 최소배지인 M9 minimal 배지를 사용한 결과 OppA protein의 생성 결핍에 따라 초기 및 대수증식기 과정 중에는 mutant의 생육이 늦어지고 있으나 Opp system이 아닌 다른 peptide전달 경로로 추정되는 system을 이용하여 대수 증식기 후반에서는 wild type과 거의 같은 생육 형태를 보여 주고 있었다. pH의 변화에 따른 생육은 pH 7에서는 생육정도가 비슷하였으나 약알칼리 부근에서는 oppA mutant의 생육이 wild type에 비하여 낮아지고 있었다. 또한 5 mM $H_2O_2$를 사용하여 $OD_{600}=1.2$농도의 세포들에 대한 영향을 검토한 결과 두 균 모두 높은 생존율을 보여 주었으며 이는 대수증식기 세포들을 사용한 결과와는 매우 다른 형태를 보여 주고 있었다. 항생제 내성에 대한 연구에서는 mutant가 streptomycin과 tetracycline 에 대해서는 wild type과는 다르게 매우 낮은 농도에서도 생육이 되고 있지 않으나 polymyxin B에 대해서는 wild type과 같이 $10{\mu}g/ml$의 농도에서도 잘 자라고 있었다.