• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.32-32
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• 2017

To increase rice production, manipulating plant architecture, especially developing new high-yielding cultivars with erect leaves, is crucial in rice breeding programs. Leaf inclination angle determines the light extinction coefficient (k) of the canopy. Erect leaves increase light penetration into the canopy and enable dense plantings with a high leaf area index, thus increasing biomass production and grain yield. Because of erect leaves, the high-yielding indica rice cultivar 'Takanari' has smaller k during ripening than 'Koshihikari', a japonica cultivar with good eating quality. In our previous study, using chromosome segment substitution lines (CSSLs) derived from a cross between 'Takanari' and 'Koshihikari', we detected seven quantitative trait loci (QTLs) for leaf inclination angle on chromosomes 1 (two QTLs), 2, 3, 4, 7, and 12. In this study, we developed a near-isogenic line (NIL-3) carrying a 'Takanari' allele for increased leaf inclination angle on chromosome 3 in the 'Koshihikari' genetic background. We compared k, dry matter production, and grain yield of NIL-3 with those of 'Koshihikari' in the field from 2013 to 2016. NIL-3 had higher inclination angles of the flag, second, and third leaves at full heading and 3 (- 4) weeks after full heading and smaller k of the canopy at the ripening stage. Biomass at full heading and leaf area index at full heading and at harvest did not significantly differ between NIL-3 and 'Koshihikari'. However, biomass at harvest was significantly greater in NIL-3 than in 'Koshihikari' due to a higher net assimilation rate at the ripening stage. The photosynthetic rates of the flag and third leaves did not differ between NIL-3 and Koshihikari at ripening. Grain yield was higher in NIL-3 than 'Koshihikari'. Higher panicle number per square meter in NIL-3 contributed to the higher grain yield of NIL-3. We conclude that the QTL on chromosome 3 increases dry matter and grain production in rice by increasing leaf inclination angle.

• Asian-Australasian Journal of Animal Sciences
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• 제33권11호
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• pp.1725-1731
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• 2020

Objective: An initial RNA-Sequencing study revealed that UDP-galactose-4-epimerase (GALE) was one of the most promising candidates for milk protein concentration in Chinese Holstein cattle. This enzyme catalyzes the interconversion of UDP-galactose and UDP-glucose, an important step in galactose catabolism. To further validate the genetic effect of GALE on milk protein traits, genetic variations were identified, and genotypes-phenotypes associations were performed. Methods: The entire coding region and the 5'-regulatory region (5'-UTR) of GALE were re-sequenced using pooled DNA of 17 unrelated sires. Association studies for five milk production traits were performed using a mixed linear animal model with a population encompassing 1,027 Chinese Holstein cows. Results: A total of three variants in GALE were identified, including two novel variants (g.2114 A>G and g.2037 G>A) in the 5'-UTR and one previously reported variant (g.3836 G>C) in an intron. All three single nucleotide polymorphisms (SNPs) were associated with milk yield (p<0.0001), fat yield (p = 0.0006 to <0.0001), protein yield (p = 0.0232 to <0.0001) and protein percentage (p<0.0001), while no significant associations were detected between the SNPs and fat percentage. A strong linkage disequilibrium (D' = 0.96 to 1.00) was observed among all three SNPs, and a 5 Kb haplotype block involving three main haplotypes with GAG, AGC, and AGG was formed. The results of haplotype association analyses were consistent with the results of single locus association analysis (p<0.0001). The phenotypic variance ratio above 3.00% was observed for milk protein yield that was explained by SNP-g.3836G >C. Conclusion: Overall, our findings provided new insights into the polymorphic variations in bovine GALE gene and their associations with milk protein concentration. The data indicate their potential uses for marker-assisted breeding or genetic selection schemes.

• Mycobiology
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• 제39권4호
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• pp.235-242
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• 2011

In contrast to the nuclear genome, the mitochondrial genome does not follow Mendelian laws of inheritance. The nuclear genome of meiotic progeny comes from the recombination of both parental genomes, whereas the meiotic progeny could inherit mitochondria from one, the other, or both parents. In fact, one fascinating phenomenon is that mitochondrial DNA in the majority of eukaryotes is inherited from only one particular parent. Typically, such unidirectional and uniparental inheritance of mitochondrial DNA can be explained by the size of the gametes involved in mating, with the larger gamete contributing towards mitochondrial DNA inheritance. However, in the human fungal pathogen Cryptococcus neoformans, bisexual mating involves the fusion of two isogamous cells of mating type (MAT) a and MAT${\alpha}$, yet the mitochondrial DNA is inherited predominantly from the MATa parent. Although the exact mechanism underlying such uniparental mitochondrial inheritance in this fungus is still unclear, various hypotheses have been proposed. Elucidating the mechanism of mitochondrial inheritance in this clinically important and genetically amenable eukaryotic microbe will yield insights into general mechanisms that are likely conserved in higher eukaryotes. In this review, we highlight studies on Cryptococcus mitochondrial inheritance and point out some important questions that need to be addressed in the future.

• 한국산학기술학회논문지
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• 제17권7호
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• pp.529-535
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• 2016

이론적 연구를 통하여 정수압의 영향을 받는 항복기준인 Mohr-Coulomb 항복기준과 Drucker-Prager 항복기준의 강도정수를 ${\pi}$-평면에 대해 일치시킴으로써 강도정수간의 상관관계를 분석해 보았다. Drucker-Prager 강도정수 ${\alpha}$와 k를 Mohr-Coulomb 강도정수인 c와 ${\phi}$를 이용하여 표현하였는데 k는 c, ${\phi}$의 함수로 표현되었고 ${\alpha}$는 ${\phi}$만의 함수로 표현되었다. Drucker-Prager 강도정수 ${\alpha}$값은 흙의 내부마찰각이 커짐에 따라 증가함을 알 수 있었는데 Drucker-Prager 항복기준을 나타내는 원이 Mohr-Coulomb 항복기준에 외접 및 내접하는 경우의 ${\alpha}$값을 나타내는 ${\alpha}_c$와 ${\alpha}_i$값에 대하여 평균값인 ${\alpha}_{av}$의 값은 내부마찰각에 비례하였는데 내부마찰각이 $10^{\circ}$인 경우 약 0.07이었으며 내부마찰각이 $45^{\circ}$인 경우 약 0.29이었다. 또한, ${\alpha}_c/{\alpha}_i$값은 내부마찰각에 비례하였는데 내부마찰각이 $10^{\circ}$인 경우 약 1.12이었으며 내부마찰각이 $45^{\circ}$인 경우 약 1.62이었다. Mohr-Coulomb 강도정수가 Drucker-Prager 강도정수 k에 미치는 영향을 살펴보았는데 본 연구에서 가정한 흙의 점착력 중 최소값이 10kPa인 경우를 제외하고 흙의 내부마찰각의 영향을 거의 받지 않고 전체적으로 흙의 점착력에 영향을 받음을 알 수 있었다. 일정한 점착력에 대하여 내부마찰각이 증가함에 따라 일축압축시 및 일축인장시의 Mohr-Coulomb 항복기준에 의한 축차응력인 $S_{c0}$와 $S_{t0}$ 그리고 두 값의 평균값인 $S_{0(ave)}$값은 감소하였다. 또한 내부마찰각이 증가할수록 Mohr-Coulomb 항복궤적을 나타내는 육각형이 더욱 불규칙해져 $S_{0(ave)}$로부터 $S_{c0}$와 $S_{t0}$ 사이의 편차가 내부마찰각이 증가함에 따라 커짐을 알 수 있었다.

• 한국육종학회지
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• 제49권3호
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• pp.280-284
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• 2017

화성벼의 유전적 배경에 O. minuta의 유용유전자가 이입된 근동질계통을 육성하기 위해 화성벼와 O. minuta를 교배하고, 계속적인 여교배와 MAS를 병행 실시하여 유망계통 CR1135-64-2를 선발하였다. CR1135-64-2는 생산력검정 시험 결과 조사된 형질 중 수당립수를 제외한 기타 형질은 화성벼와 유사한 근동질계통으로, 품종보호 출원 조건에 부합하여 '화원6호'로 명명하고 품종보호원을 출원하였다. '화원6호'는 출수기가 보통기재배에서 8월 12일로 화성벼와 유사한 중생종 품종이다. 현미천립중은 21.9g으로 화성벼보다 무거웠으나 통계적으로 유의한 차이는 없었다. '화원6호'는 줄무늬잎마름병을 제외한 다른 병해충에는 약한 반응을 보였으며, 완전미율은 화성벼에 비해 약간 낮았고, 아밀로스 함량은 화성벼와 유사하였으나 통계적인 차이는 없었다. '화원6호'의 정조수량은 '09~'10년 2개년간 실시한 생산력 검정 시험에서 평균 6.57 MT/ha로 화성벼 대비 103% 수준이었다. '화원6호'는 화성벼에 비해 수당립수가 많았는데 이는 O. minuta에서 이입된 qSPP7 유전자의 영향으로 판단된다.(품종보호권 등록번호: 제 5133호)

• 대한치과교정학회지
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• 제34권2호
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• pp.177-188
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• 2004

교정치료 시기의 적기이며 내원 환자의 많은 부분을 차지하고 있는 청소년기 교정환자의 치료 협조도에 영향을 미치는 요소들에 대해 파악하고자 강릉대학교 치과병원 교정과에서 10개월 이상 동적 치료를 받은 중학교 1학년 이상, 고등학교 3학년 이하 남녀 청소년 60명 (남자 23명, 여자 37명)을 대상으로 인구학적 변인에 따른 치료 협조도를 비교하고 성별, 학령, 치료 협조도에 따른 교정적 태도 척도, 교정용 내외통제소재 척도를 측정, 비교 분석하여 다음과 같은 결과를 얻었다. 1. 교정용 내외통제소재 척도를 조사 분석한 결과 외적통제-부모의 항목에서 성별에 따라 유의한 차이가 인정되었으며(p<0.05) 남학생이 여학생보다 높은 외적통제-부모의 양상을 나타내었다. 2. 교정용 내외통제소재 척도를 조사 분석한 결과 협조적인 환자 군과 비협조적인 환자 군간에 외적통제-부모 항목에서 유의성 있는 차이가 인정되었으며(p<0.05) 교정치료에 대해 협조적인 군에서 외적통제-부모에 대한 인식이 보다 높았다. 3. 교정 치료를 권유하거나 치료받기를 결정한 사람과 치료시의 협조도 사이에는 통계적으로 유의한 차이가 인정되었으며(p<0.05) 환자 자신의 결정에 의한 경우 가장 높은 협조도를 나타내었다. 4. 치료기간과 협조도 사이에 유의한 차이가 인정되었으며 (p<0.05) 치료기간이 길어질수록 협조도는 지속적으로 감소하였다. 5. 교정적 태도 척도를 조사 분석한 결과 성별, 중학생과 고등학생간, 협조적인 환자군과 비협조적인 환자군 사이 에 통계적으로 유의한 차이가 없었다. 6. 교정치료 시 협조정도와 한자의 성별, 연령, 가족관계, 부모의 직업 및 학력, 학업성적, 양치횟수 등의 변인과는 통계적으로 유의한 차이가 인정되지 않았다.

• Molecules and Cells
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• 제37권2호
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• pp.149-160
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• 2014

Plant breeders have focused on improving plant architecture as an effective means to increase crop yield. Here, we identify the main-effect quantitative trait loci (QTLs) for plant shape-related traits in rice (Oryza sativa) and find candidate genes by applying whole genome re-sequencing of two parental cultivars using next-generation sequencing. To identify QTLs influencing plant shape, we analyzed six traits: plant height, tiller number, panicle diameter, panicle length, flag leaf length, and flag leaf width. We performed QTL analysis with 178 $F_7$ recombinant inbred lines (RILs) from a cross of japonica rice line 'SNU-SG1' and indica rice line 'Milyang23'. Using 131 molecular markers, including 28 insertion/deletion markers, we identified 11 main- and 16 minor-effect QTLs for the six traits with a threshold LOD value > 2.8. Our sequence analysis identified fifty-four candidate genes for the main-effect QTLs. By further comparison of coding sequences and meta-expression profiles between japonica and indica rice varieties, we finally chose 15 strong candidate genes for the 11 main-effect QTLs. Our study shows that the whole-genome sequence data substantially enhanced the efficiency of polymorphic marker development for QTL fine-mapping and the identification of possible candidate genes. This yields useful genetic resources for breeding high-yielding rice cultivars with improved plant architecture.

• 한국동물학회지
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• 제13권3호
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• pp.75-84
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• 1970

蛋白質의 放射線分解의 기작을 밝히는 연구의 일환으로, 특히 peptide 結合의 분해의 기작을 구명하기 위하여 Glycylglycylglycine의 水溶液과 固體를 酸素의 존재하에서와 無酸素하에서 r 線을 조사하여 分解生成物을 여지크로마토그라프로 분리하였고, carbonyl 化合物과 amide를 각각 分光光度法과 微凉摘定法으로 정량하였으나 放射線障害를 평가하기 위하여 赤外線 spectrum과 紫外線 spectrum을 얻어 검토하였다. 水溶液과 固體에 있어서의 peptide 結合의 분해기작은 근본적인 차이가 있는 것으로 여겨지며, 전자에서는 월등하게 분해가 많이 일어난데 반해서 후자에서는 무시할 정도에 지나지 않았다. 한편, 水溶液의 경우 酸素의 유무에 따라 현저한 영향은 보이지 않았으나 無酸素하에서는 遊離基의 再結合이 일어나는 점이 특기할만 하였다. 水溶液에 있어서의 peptide 結合의 분해기구는 Garrison 一派가 주장한 기작에 의해서 일어나는 것이 분명하여 脫水素反應에 뒤이어 加水分解反應에 의해서 amide 와 carbonyl 이 생성되는 것으로 보이며, 固體의 경우도 $\\alpha$-炭素의 부위가 방사선의 공격을 가장 많이 받는 것으로 추정되나 그 정도는 미미한 것에 지나지 않는 것으로 생각되었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.113-113
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• 2017

Downy mildew (DM), caused by several species in the Peronosclerospora and Scleropthora genera, is a major maize (Zea mays L.) disease in tropical or subtropical regions. DM is an obligate parasite species in the higher plants and spreads by oospores, wind, and mycelium in seed surface, soil, and living hosts. Owing to its geographical distribution and destructive yield reduction, DM is one of the most severe maize diseases among the maize pathogens. Positional cloning in combination with phenotyping is a general approach to identify disease resistant gene candidates in plants; however, it requires several time-consuming steps including population or fine mapping. Therefore, in the present study, we suggest a new combination strategy to improve the identification of disease resistant gene candidates. Downy mildew (DM) resistant maize was selected from five cultivars using the spreader row technique. Positional cloning and bioinformatics tools identified the DM resistant QTL marker (bnlg1702) and 47 protein coding genes annotations. Eventually, 5 DM resistant gene candidates, including bZIP34, Bak1, and Ppr, were identified by quantitative RT-PCR without fine mapping of the bnlg1702 locus. Specifically, we provided DM resistant gene candidates with our new strategy, including field selection by the spreader row technique without population preparation, the DM resistance region identification by positional cloning using bioinformatics tools, and expression level profiling by quantitative RT-PCR without fine mapping. As whole genome information is available for other crops, we propose applying our novel protocol to other crops or for other diseases with suitable adjustment.

• 한국작물학회지
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• 제44권1호
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• pp.86-94
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• 1999

A set of rice recombinant inbred lines was developed from a cross between a Tongil type variety, Nonganbyeo, and an indica variety, BG276, by the single seed descent method. The number of the lines in the population was 272. All the agronomic characters studied except ADV (alkali-digestion value) showed continuous variation among the RILs, implying that their inheritance mode should be quantitative. The patterns of the variation in the RILs were either normal or skewed distribution. ADVs of RILs were segregated into two groups with 1:1 ratio, indicating that ADVs in this KIL population might be controlled by one major gene. Transgressive variations were also observed in all characters. Heritability values of the characters varied from 0.488 in brown/rough rice ratio to 0.895 in alkali-digestion value. In the analysis of genotypic and phenotypic correlations, the character of yield was positively correlated with 8 different agronomic characters. The number of panicles per hill was negatively correlated with culm length, panicle length, and number of spikelets per panicle. Grain length was positively correlated with grain width, grain thickness, grain length/width ratio, white belly, ADV, and amylose. However, grain length/width ratio was negatively correlated with grain width. White core was also negatively correlated with white belly and ADV.