• Journal of Microbiology
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• v.44 no.5
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• pp.523-529
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• 2006

OSH3 is one of the seven yeast homologues of the oxysterol binding proteins (OSBPs) which have the major binding affinity to the oxysterols and function as regulator of cholesterol biosynthesis in mammals. Mutational analysis of OSH3 showed that OSH3 plays a regulatory role in the yeast-to-hyphal transition through its oxysterol-binding domain in Saccharomyces cerevisiae. The OSH3 gene was also identified in the pathogenic yeast Candida albicans. Deletion of OSH3 caused a defect in the filamentous growth, which is the major cause of the C. albicans pathogencity. The filamentation defect of the mutation in the MAPK-associated transcription factor, namely $cph1{\Delta}$ was suppressed by overexpression of OSH3. These findings suggest the regulatory roles of OSH3 in the yeast filamentous growth and the functional conservations of OSH3 in S. cerevisiae and C. albicans.

• 보존과학연구
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• s.25
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• pp.47-74
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• 2004

We investigated the nucleotide substitution and insertion polymorphism of the hypervariable region Ⅰ and Ⅱ in mt DNA by sequencing ancient DNA from 51 ancient bones and teeth excavated at Nuk-do and Yimdang-dong in Korea. It revealed 35 sequence types from the ancient Korean. Of these, different sequences were 34 sequences. There were 19 and 38 base substitutions in HVI and HVⅡ, respectively. Some substitutions were characteristic of East Asian populations as compared with data reported on Caucacianpopulations,16051, 16150, 16172, 16223 in region I and 73, 263 in region II were noted as polymorphic sites, respectively. These were distributed evenly along the control region, though the frequency of each site was variable. Nucleotide substitution rather than insertion and deletion was the prevalent pattern of variation. Insertion of cytosine between312 and 315 in region HVⅡ were detected up to 98% in 51 ancient bone samples. This sequence data represents a phylogenetic tree using NTI DNA Suite computer program. The phylogenetic tree showed that mt DNA sequences of Nuk-do bones were relative to west Siberian and Indonesian. The usefulness of mt DNA sequencing in ancient Korean population excavated atarchaeological sites is based on biological and historical evidence for origin and migration of ancient Korean.

• Korean Journal of Agricultural Science
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• v.36 no.2
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• pp.159-165
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• 2009

This study was conducted to identify the PERV (Porcine Endogenous Retrovirus) integration sites and their characterizations using the porcine genomic sequence information. Total 114 Mb (4.2%) sequence of the 2.7 Gb pig genome was investigated for the PERV sequences. As the results, 8 PERV sequences were identified and their genomic structures were deduced from the BLAST searches against previously known PERV genes. Seven PERVs have internal deletions in the protein coding region and they will not be functional. The other one also has internal deletions in the gag and env genes, indicating this PERV is also defective. Even though we could not identify the functional PERVs in this study, the results presented here can be used for the fundamental research materials for controlling PERV infections in relation to xenotransplantation using porcine organs and tissues.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.19 no.3 s.73
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• pp.303-312
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• 2006

This paper presents the equivalent nodal load for the element stiffness which represents the influence of the stiffness change such as the addition of elements, the deletion of elements, and/or the partial change of element stiffness. The reanalysis of structure using the equivalent load improves the efficiency very much because the inverse of the structural stiffness matrix, which needs a large amount of computation to calculate, is reused in the reanalysis. In this paper, the concept of the equivalent load for the element stiffness is described and some numerical examples are provided to verify it.

• Molecules and Cells
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• v.38 no.6
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• pp.540-547
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• 2015

Attention deficit/hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders, affecting approximately 5% of children. However, the neural mechanisms underlying its development and treatment are yet to be elucidated. In this study, we report that an ADHD mouse model, which harbors a deletion in the Git1 locus, exhibits severe astrocytosis in the globus pallidus (GP) and thalamic reticular nucleus (TRN), which send modulatory GABAergic inputs to the thalamus. A moderate level of astrocytosis was displayed in other regions of the basal ganglia pathway, including the ventrobasal thalamus and cortex, but not in other brain regions, such as the caudate putamen, basolateral amygdala, and hippocampal CA1. This basal ganglia circuit-selective astrocytosis was detected in both in adult (2-3 months old) and juvenile (4 weeks old) $Git1^{\check{s}/\check{s}}$ mice, suggesting a developmental origin. Astrocytes play an active role in the developing synaptic circuit; therefore, we performed an immunohistochemical analysis of synaptic markers. We detected increased and decreased levels of GABA and parvalbumin (PV), respectively, in the GP. This suggests that astrocytosis may alter synaptic transmission in the basal ganglia. Intriguingly, increased GABA expression colocalized with the astrocyte marker, GFAP, indicative of an astrocytic origin. Collectively, these results suggest that defects in basal ganglia circuitry, leading to impaired inhibitory modulation of the thalamus, are neural correlates for the ADHD-associated behavioral manifestations in $Git1^{\check{s}/\check{s}}$ mice.

• BMB Reports
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• v.48 no.1
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• pp.19-24
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• 2015

A mouse homozygous for the spontaneous mutation uncovered (Uncv) has a hairless phenotype. A 309-bp non-frameshift deletion mutation in the N-terminal cytoplasmic domain of iRhom2 was identified in Uncv mice ($iRhom2^{Uncv}$) using target region sequencing. The detailed molecular basis for how the iRhom2 mutation causes the hairless phenotype observed in the homozygous $iRhom2^{Uncv}$ mouse remains unknown. To identify differentially expressed proteins in the skin of wild-type and homozygous $iRhom2^{Uncv}$ littermates at postnatal day 5, proteomic approaches, including two-dimensional gel electrophoresis and mass spectrometry were used. Twelve proteins were differentially expressed in the skin in a comparison between wild-type and homozygous $iRhom2^{Uncv}$ mice. A selection of the proteomic results were tested and verified using qRT-PCR, western blot and immunohistochemistry. These data indicate that differentially expressed proteins, especially KRT73, MEMO1 and Coro-1, might participate in the mechanism by which iRhom2 regulates the development of murine skin.

• The Plant Pathology Journal
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• v.25 no.3
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• pp.236-240
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• 2009

Tylenchulus semipenetrans, citrus nematode is an important phytopathogenic nematode and responsible for serious damage on citrus. However, little information is available about genetic variability of T. semipenetrans among different populations with variation of conventional diagnostic characteristics. In this study, we compared the morphometric and genetic characteristics among different populations. The mature female of T. semipenetrans collected in this study had thicker cuticle than those in the previous studies. In comparative sequence analysis of T. semipenetrans populations obtained from Jeju in Korea, we observed genetic variations within clones generated from single individuals. To determine whether variability among copies of nuclear ribosomal DNA sequences exists in the genome of T. semipenetrans, PCR-RFLP technique from individuals of Korean isolates with MseI and MspI restriction enzymes was used to prove experimentally that all populations have intra-specific variations. Restriction enzyme digestion created several fragments on 3.0% agarose gel corresponding to several haplotypes in all populations, though some populations displayed fragment deletion. The total length of fragments was larger than before digestion, indicating sequence heterogeneity within the genome of T. semipenetrans.

• Journal of Families and Better Life
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• v.26 no.4
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• pp.41-54
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• 2008

The purpose of this study was to investigate predictors concerning preschoolers' ability to read words, in terms of their sub-skills of alphabet knowledge, phonological awareness, and phonological processing. Fourteen literacy sub-tests and three types of reading tasks were administered to 289 kindergartners aged 4 to 6 in Busan. The main results are as follows. Sub-skills that predicted reading ability varied with children's age. Irrespective of children's age groups, knowledge of consonant names and digit naming speed commonly explained the reading of real words. In contrast, skills of syllable deletion and phoneme substitution and knowledge of alphabet composition principles were related to only 4-year-olds' reading skills. Exclusively included was digit memory in predicting 5-year-olds' reading abilities, and knowledge of vowel sounds in 6-year-olds' reading skills. The type of reading task also influenced reading ability. A few common variables such as knowledge of consonant names and vowel sounds, digit naming speed, and phoneme substitution skill explained all types of word reading. Syllable counting skills, however, had predictive value only for the reading of real words. Phoneme insertion skills and digit memory had predictive value for the reading of pseudo words and low frequency letters. Likewise, knowledge of consonant sounds and vowel stroke-adding principles were significant only for the reading of low frequency letters.

• Bulletin of Food Technology
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• v.8 no.4
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• pp.179-191
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• 1995

Thermoanaerobacter ethanolicus유래 thermophilic amylopullulanase의 thermophilicity와 thermostability의 기작을 규명하기 위하여 N-말단과 C-말단으로부터 nested deletion mutatnt와 sitedirected mutagenesis등에 의한 변이효소를 제조, 분석하였다. 이러한 까다로운 변이효소를 제조하여 amylopullulanase의 특정부위가 효소의 thermophilicity와 thermostability에 관여하고 있는 것을 확인했다. N-말단의 start amino acid에서 194와 324 아미노산잔기에 이르는 부위 (TPR)가 이 효소의 높은 최적반응온도의 유지에 관련되어 있고 1102와 1224잔기에 이르는 부위 (TSR)는 thermodenaturation이 잘 일어나지 않도록 하고 있었다. 야생형 amylopullulanase (Apu), 변이효소중 ApuN342와 ApuN106/C379는 비슷한 효소비활성과 Km값을 가지고 있었다. TPR부위의 site-directed mutagenesis에 의한 변이효소중 P240A (proline$\rightarrow$alanine), P244A, P240A-P244A는 야생형의 최적반응온도 $80^{\circ}C$와 똑같았지만 효소의 열안전성(반감기)는 $85^{\circ}C$에서 21, 105, 128분을 보여 주었다. TSR에서의 변이효소중 P1159A, P1202A는 열안전성은 비슷하였지만 반응최적온도는 $85^{\circ}C$와 $90^{\circ}C$로 야생형 Apu보다 오히려 높아졌다. 따라서 proline은 분자내에서 thermophilicity와 thermostability를 항상 증가시키는 쪽으로 영향을 주지 않는 것으로 보인다. Proline은 그 위치와 주위의 다른 아미노산잔기와 같이 종합적으로 분자의 구조에 영향을 미치고 있는 것으로 판단된다.

• Parasites, Hosts and Diseases
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• v.39 no.2
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• pp.143-150
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• 2001

The present study was designed to investigate polymorphism in Duffy binding protein (DBP) gene of Plasmodium vivax isolates of Korea. Thirty samples were obtained from P. vivax patients in Yonchon-gun, Kyonggi-do in 1998. The PCR products of the samples were subjected to sequencing and hybridization analyses of the regions II and IV of P. vivax DBP gene. Two genotypes, SK-1 and SK-2, were identified on the basis of amino acid substitution and deletion. The genotype of 10 isolates was SK-1 and that of 20 isolates was SK-2. Most of the predicted amino acids in the region ll of DBP gene were conserved between the Korean isolates and Belem strain except for 4-5 amino acid substitutions. In the region W of DBP, a 6-bp insert that was shown in the Sal-1 allele type was found in SK-1, and a 27-bp insert that was shown in the Papua New Guinea allele type was found in SK-2. In conclusion, the present findings suggest that two genotypes of P. vivax coexist in the endemic area of Korea.