• Molecules and Cells
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• 제37권1호
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• pp.74-80
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• 2014

The peroxisome is an intracellular organelle that responds dynamically to environmental changes. Various model organisms have been used to study the roles of peroxisomal proteins in maintaining cellular homeostasis. By taking advantage of the zebrafish model whose early stage of embryogenesis is dependent on yolk components, we examined the developmental roles of the D-bifunctional protein (Dbp), an essential enzyme in the peroxisomal ${\beta}$-oxidation. The knockdown of dbp in zebrafish phenocopied clinical manifestations of its deficiency in human, including defective craniofacial morphogenesis, growth retardation, and abnormal neuronal development. Overexpression of murine Dbp rescued the morphological phenotypes induced by dbp knockdown, indicative of conserved roles of Dbp during zebrafish and mammalian development. Knockdown of dbp impaired normal development of blood, blood vessels, and most strikingly, endoderm-derived organs including the liver and pancreas - a phenotype not reported elsewhere in connection with peroxisome dysfunction. Taken together, our results demonstrate for the first time that zebrafish might be a useful model animal to study the role of peroxisomes during vertebrate development.

• 미생물학회지
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• 제43권4호
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• pp.325-330
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• 2007

대장균의 필수적인 리보핵산 내부분해효소인 RNase E는세포내에서 여러 RNA의 분해와 가공과정에서 중요한 역할을 하며, 이 단백질의 효소활성부위를 포함하는 N-말단부위의 498 아미노산(N-Rne)만의 발현으로도 세포의 생장을 가능하게 한다. 이러한 RNase E의 특성을 활용하여 다양한 표현형을 가지는 N-Rne 돌연변이체들을 분리, 동정할 수 있는 효율적인 유전학적 시스템을 개발하였다. 이 시스템을 이용하여 얻어진 효소활성부위 돌연변이체들을 표현형으로 분류하여 분석한 결과, S1 도메인의 6번째 아미노산의 치환(I6T)을 가진 변이체는 야생형 N-Rne의 기능을 대체하지 못하였고, Small 도메인의 488번째 아미노산의 치환(R488C)을 가진 변이체는 야생형 N-Rne의 발현양보다 현저히 작게 발현시켜도 세포의 생장을 정상적으로 가능하게 하였다. 또한 DNase I 도메 인의 305번째 아미노산의 치환(N305D)을 가진 변이체는 야생형 N-Rne의 발현양보다 과발현시켰을 때만 세포의 생장을 가능하게 하였다. 각각의 아미노산 치환을 포함하는 N-Rne를 한정적으로 과발현시켰을 때의 ColEl-타입 플라스미드의 복제 수에 대한 영향을 측정한 결과, 돌연변이체 N-Rne의 세포생장에 대한 영향은 이 변이체들의 세포 내 효소활성 정도에 기인하는 것으로 밝혀졌다. 이러한 실험결과는 이 연구에서 개발한 유전학적 시스템을 이용하여 다양한 표현형을 가진 RNase E 변이체를 선별할 수 있으며, 이 변이체들의 특성을 분석함으로써 RNase E가 RNA의 안정성을 조절하는데 있어서 각각의 세부 도메인의 역할을 규명할 수 있으리라는 것을 시사한다.

• 한국잡초학회지
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• 제8권3호
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• pp.250-257
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• 1988

Bensulfuron에 대표적인 내성군(耐性群)(UCP-28, Chinsurah Boro II, Fukunohama, Fadehpur-2, IR 14252-13-2-2-5)과 감수성품종군(感受性品種群)(HP93(3) FA, HP94(9) FA, Padilabou Alumbis. KH-17854, IR 1846-2841-1)을 공시(供試)하여 종실(種實) 단백질(蛋白質)(SDS-PAGE)과 유묘(幼苗) 동위효소(同位酵素)(malate dehydrogenase, acid phosphatase, peroxidase, esterase: 7% PAGE)의 전기영동(電氣泳動) profile을 분석(分析)하고, bensulfuron 0, $10^{-6}$, $10^{-5}$, $3{\times}10^{-5}M$ 용액에서 생장(生長)한 두 대표 품종(品種)(cv. Chinsurah Boro II와 cv. IR 1846)의 5 일령(日齡) 유묘(幼苗)의 동위효소(同位酵素) profile 변화양상(變化樣相)을 비교(比較)하므로써, bensulfuron에의 내성차이(耐性差異)와 이들 전기영동(電氣泳動) profile 차이(差異)가 갖는 연관성(聯關性)을 알고저 하였다. 결과(結果)를 요약(要約)하면 다음과 같다. 1. 종실단백(種實蛋白)의 전기영동(電氣泳動)으로 16개(個) band를 확인(確認)할 수 있었고, 이를 근거(根據)로 clustering한 결과(結果), 내성(耐性)에서의 M, O, P band가 높게 나타났고 또한 전체 peak 면적(面積)이 크다는 특이성(特異性)에 기인(起因)하여 두 품종군간(品種群間)에 비유사성(非類似性)이 인정(認定)되는 정도(程度)로 분류(分類)되었다. 2. 무처리(無處理)된 유묘(幼苗)의 동위효소(同位酵素) 가운데, peroxidase로는 4개(個) band가 얻어졌고, 내성군(耐性群)의 특이성(特異性)은 D band에서의 활성(活性)이 높은 데 있었다. Malate dehydrogenase는 3개(個) band로 분리(分離)되었고, 내성군(耐性群)만이 A band를 나타내며 B 및 C band도 내성군(耐性群)에서 선명하였다. Esterase는 3~4개(個) band로 구분(區分)되었고 내성군(耐性群)이 A 및 B band에서 높은 활성(活性)을 보였다. Acid phosphatase는 하나의 major band와 2~3개(個)의 minor band로 나타났으며 내성군(耐性群)만은 B band를 갖는 경향(傾向)이었다. 3. Bensulfuron의 처리농도(處理濃度)에 따라, 동위효소(同位酵素) 가운데 peroxidase는 감수성(感受性)에서만 C band의 생성(生成)과 D band의 소실현상(消失現象)이 야기(惹起)되었고, 내성품종(耐性品種)에서는 C band가 나타나지 않았으며, 다른 band에서의 변화(變化)도 없었다. Malate dehyrogenase의 경우, major band인 D, E, F는 감수성(感受性)에서 활성(活性)이 컸고 변화(變化)는 없었으며, minor band인 A, B, C는 감수성(感受性)에서만 민감(敏感)하게 소실(消失)되었다. Esterase는 5개(個) band로 표현(表現)되었으며 내성(耐性)에서는 A, B, C, D 감수성(感受性)에서는 A, B, C, E만 나타났으며, 약처리농도증가(藥處理濃度增加)로 감수성품종(感受性品種)은 A, C, E band의 활성(活性)이 민감(敏感)하게 소실(消失)되었다.

• 생명과학회지
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• 제19권3호
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• pp.384-389
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• 2009

본 연구는 한우, 제주흑우, Holstein에서 모색 발현 양상과 MC1R 유전자형의 분포에 따라 melanin 합성에 핵심적인 과정에 참여하는 3 가지 유전자(TYR, TYRP1, DCT) 유전자들의 발현 수준의 상호 연관관계를 구명하기 위하여 수행되었다. 반정량 Real-time RT-PCR 분석을 통하여, 세 가지 유전자의 발현 수준을 MC1R 유전자형이 e/e인 한우의 황갈색 부위, $E^+/E^+$인 제주흑우의 야생형 흑색 부위, $E^D/E^D$인 Holstein의 우성 흑반과 백반부로 대표되는 4 종류의 피부 조직에서 분석하였다. TYR, TYRP1, DCT 유전자 모두 Holstein의 흑반 부위에서 제주흑우의 흑색 부위에 비해 각각 4.5 배, 2.3 배, 2.5 배 이상의 유전자 발현 수준을 나타내었다(p<0.001). 또한, 제주 흑우의 이들 3 가지 유전자들의 발현 수준은 한우에 비해 유의적으로 높은 수준을 나타내었다(p<0.001). 이러한 결과들은 한우와 제주흑우, Holstein의 흑색 부위의 모색 발현 양상들이 이들 3 가지 melanin 생합성 유전자들의 전사 수준과 직접적인 연관이 있는 것으로 사료되며, 이는 한우 e/e, 제주흑우 $E^+/E^+$ Holstein의 $E^D/E^D$ 등 서로 상이한 MC1R 유전자형의 관여가 반영된 결과로 추정되었다. 결론적으로 본 연구는 MC1R 단백질의 상태가 TYR과 일련의 melanin 합성 주관 유전자들의 전사활성을 유도할 뿐만 아니라 소의 피부에서 총 melanin 함량의 수준을 결정함을 제시하고 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제23권4호
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• pp.417-424
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• 2010

The purpose of this study was to detect significant SNPs for carcass quality traits using DNA chips of high SNP density in Hanwoo populations. Carcass data of two hundred and eighty nine steers sired by 30 Korean proven sires were collected from two regions; the Hanwoo Improvement Center of National Agricultural Cooperative Federation in Seosan, Chungnam province and the commercial farms in Gyeongbuk province. The steers in Seosan were born between spring and fall of 2006 and those in Gyeonbuk between falls of 2004 and 2005. The former steers were slaughtered at approximately 24 months, while the latter steers were fed six months longer before slaughter. Among the 55,074 SNPs in the Illumina bovine 50K chip, a total of 32,756 available SNPs were selected for whole genome association study. After adjusting for the effects of sire, region and slaughter age, phenotypes were regressed on each SNP using a simple linear regression model. For the significance threshold, 0.1% point-wise p value from F distribution was used for each SNP test. Among the significant SNPs for a trait, the best set of SNP markers were selected using a stepwise regression procedure, and inclusion and exclusion of each SNP out of the model was determined at the p<0.001 level. A total of 118 SNPs were detected; 15, 20, 22, 28, 20, and 13 SNPs for final weight before slaughter, carcass weight, backfat thickness, weight index, longissimus dorsi muscle area, and marbling score, respectively. Among the significant SNPs, the best set of 44 SNPs was determined by stepwise regression procedures with 7, 9, 6, 9, 7, and 6 SNPs for the respective traits. Each set of SNPs per trait explained 20-40% of phenotypic variance. The number of detected SNPs per trait was not great in whole genome association tests, suggesting additional phenotype and genotype data are required to get more power to detect the trait-related SNPs with high accuracy for estimation of the SNP effect. These SNP markers could be applied to commercial Hanwoo populations via marker-assisted selection to verify the SNP effects and to improve genetic potentials in successive generations of the Hanwoo populations.

• 원예과학기술지
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• 제30권3호
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• pp.286-293
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• 2012

고추에 있어서 Tobamovirus 저항성은 고추 염색체 11번 긴 팔 끝부분에 위치한 L 유전자좌의 다섯 개 대립유전자($L^0$, $L^1$, $L^2$, $L^3$, and $L^4$)에 의해 조절된다고 알려져 있다. 표현형 분석 없이 L 대립유전자를 구분할 수 있는 분자표지를 개발하기 위해서 다섯 개의 고추 판별 계통{Capsicum annuum Early California Wonder(ECW, $L^0L^0$), C. annuum Tisana($L^1L^1$), C. annuum Criollo de Morelos 334(CM334,$L^2L^2$), Capsicum chinense PI 159236($L^3L^3$), and Capsicum chacoense PI 260429($L^4L^4$)}을 식물재료로 사용하였다. 대립유전자 특이적 분자표지는 고추 판별 계통에 대해 $L^3$ 연관 분자표지(189D23M, A339, and 253A1R)와 BAC 염기서열(FJ597539 and FJ597541)의 PCR 증폭산물 염기서열을 비교 분석하여 개발되었다. 총 53개의 상용 고추 품종 중 48개에서 분자표지에 의한 추정 유전자형과 Tobamovirus{Tobacco mosaic virus(pathotype 0, $P_0$), Tomato mosaicvirus($P_1$), and Pepper mild mottle virus($P_{1,2}$)} 접종 표현형과 일치했다. 결과적으로 본 연구에서 개발된 분자표지는 고추 육종에 있어서 TMV 저항성 도입에 필요한 선발마커로 충분히 활용될 수 있을 것이다.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
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• pp.71-80
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• 2005

Effects of low temperature ($8^{\circ}C$) on the hydraulic conductivity of young roots of a chilling-sensitive (cucumber; Cucumis sativus L.) and a chilling-resistant (figleaf gourd; Cucurbita ficifolia Bouche) crop have been measured at the levels of whole root systems (root hydraulic conductivity, $Lp_r$) and of individual cortical cells (cell hydraulic conductivity, Lp). In figleaf gourd, there was a reduction only in hydrostatic $Lp_r$ but not in osmotic $Lp_r$ suggesting that the activity of water channels was not much affected by low root temperature (LRT)treatment in this species. Changes in cell Lp in response to chilling and recovery were similar asroot level, although they were more intense at the root level. Roots of figleaf gourd recovered better from LRT treatment than those of cucumber. In figleaf gourd, recovery (both at the root and cell level) often resulted in Lp and $Lp_r$ values which were even bigger than the original, i.e. there was an overshoot in hydraulic conductivity. These effects were larger forosmotic (representing the cell-to-cell passage of water) than for hydrostatic $Lp_r$. After a short term (1 d) exposure to $8\;^{\circ}C$ followed by 1 d at $20\;^{\circ}C$, hydrostatic $Lp_r$ of cucumber nearly recovered and that of figleaf gourd still remained higher due to the overshoot. On the contrary, osmotic $Lp_r$ and cell Lp in both species remained high by a factor of 3 as compared to the control, possibly due to an increased activity of water channels. After pre-conditioning of roots at LRT, increased hydraulic conductivitywas completely inhibited by $HgCl_2$ at both the root and cell levels. Different from figleaf gourd, recovery from chilling was not complete in cucumber after longer exposure to LRT. It is concluded that at LRT, both changes in the activity of aquaporins and alterations of root anatomy determine the water uptake in both species. To better understand the aquaporin function in plants under various stress conditions, we examined the transgenic Arabidopsisand tobacco plants that constitutively overexpress ArabidopsisPIP1;4 or PIP2;5 under various abiotic stress conditions. No significant differences in growth rates were found between the transgenic and wild-type plants under favorable growth conditions. By contrast, overexpression of PIP1;4 or PIP2;5 had a negative effect on seed germination and seedling growth under drought stress, whereas it had a positive effect under cold stress and no effect under salt stress. Measurement of water transport by cell pressure probe revealed that these observed phenotypes under different stress conditions were closely correlated with the ability of water transport by each aquaporin in the transgenic plants. Together, our results demonstrate that PIP-type aquaporins play roles in seed germination, seedling growth, and stress response of Arabidopsis and tobacco plants under various stress conditions, and emphasize the importance of a single aquaporin-mediated water transport in these cellular processes.

• Asian-Australasian Journal of Animal Sciences
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• 제23권5호
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• pp.543-555
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• 2010

The objectives of this research were the estimation of genetic parameters and trends for weaning-to-first service interval (WSI), and litter traits in a commercial swine population composed of Landrace (L), Large White (T), LT, and TL animals in Chiang Mai, Northern Thailand. The dataset contained 4,399 records of WSI, number of piglets born alive (NBA), litter weight of live piglets at birth (LBW), number of piglets at weaning (NPW), and litter weight at weaning (LWW). Variance and covariance components were estimated with REML using 2-trait analyses. An animal model was used for WSI and a sire-dam model for litter traits. Fixed effects were farrowing year-season, breed group of sow, breed group of boar (litter traits), parity, heterosis (litter traits), sow age, and lactation length (NPW and LWW). Random effects were boar (litter traits), sow, permanent environment, and residual. Heritabilities for direct genetic effects were low for WSI (0.04${\pm}$0.02) and litter traits (0.05${\pm}$0.02 to 0.06${\pm}$0.02). Most heritabilities for maternal litter trait effects were 20% to 50% lower than their direct counterparts. Repeatability for WSI was similar to its heritability. Repeatabilities for litter traits ranged from 0.15${\pm}$0.02 to 0.18${\pm}$F0.02. Direct genetic, permanent environment, and phenotypic correlations between WSI and litter traits were near zero. Direct genetic correlations among litter traits ranged from 0.56${\pm}$0.20 to 0.95${\pm}$0.05, except for near zero estimates between NBA and LWW, and LBW and LWW. Maternal, permanent environment, and phenotypic correlations among litter traits had similar patterns of values to direct genetic correlations. Boar genetic trends were small and significant only for NBA (-0.015${\pm}$0.005 piglets/yr, p<0.004). Sow genetic trends were small, negative, and significant (-0.036${\pm}$0.013 d/yr, p<0.01 for WSI; -0.017${\pm}$0.005 piglets/yr, p<0.007, for NBA; -0.015${\pm}$0.005 kg/yr, p<0.01, for LBW; -0.019${\pm}$0.008 piglets/yr, p<0.02, for NPW; and -0.022${\pm}$0.006 kg/yr, p<0.003, for LWW). Permanent environmental correlations were small, negative, and significant only for WSI (-0.028${\pm}$0.011 d/yr, p<0.02). Environmental trends were positive and significant only for litter traits (p<0.01 to p<0.0003). Selection based on predicted genetic values rather than phenotypes could be advantageous in this population. A single trait analysis could be used for WSI and a multiple trait analysis could be implemented for litter traits.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2007년도 International Meeting of the Microbiological Society of Korea
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• pp.120-122
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• 2007

All living organisms use numerous signal-transduction pathways to sense and respond to their environments and thereby survive and proliferate in a range of biological niches. Molecular dissection of these signalling networks has increased our understanding of these communication processes and provides a platform for therapeutic intervention when these pathways malfunction in disease states, including infection. Owing to the expanding availability of sequenced genomes, a wealth of genetic and molecular tools and the conservation of signalling networks, members of the fungal kingdom serve as excellent model systems for more complex, multicellular organisms. Here, we employed Cryptococcus neoformans as a model system to understand how fungal-signalling circuits operate at the molecular level to sense and respond to a plethora of environmental stresses, including osmoticshock, UV, high temperature, oxidative stress and toxic drugs/metabolites. The stress-activated p38/Hog1 MAPK pathway is structurally conserved in many organisms as diverse as yeast and mammals, but its regulation is uniquely specialized in a majority of clinical Cryptococcus neoformans serotype A and D strains to control differentiation and virulence factor regulation. C. neoformans Hog1 MAPK is controlled by Pbs2 MAPK kinase (MAPKK). The Pbs2-Hog1 MAPK cascade is controlled by the fungal "two-component" system that is composed of a response regulator, Ssk1, and multiple sensor kinases, including two-component.like (Tco) 1 and Tco2. Tco1 and Tco2 play shared and distinct roles in stress responses and drug sensitivity through the Hog1 MAPK system. Furthermore, each sensor kinase mediates unique cellular functions for virulence and morphological differentiation. We also identified and characterized the Ssk2 MAPKKK upstream of the MAPKK Pbs2 and the MAPK Hog1 in C. neoformans. The SSK2 gene was identified as a potential component responsible for differential Hog1 regulation between the serotype D sibling f1 strains B3501 and B3502 through comparative analysis of their meiotic map with the meiotic segregation of Hog1-dependent sensitivity to the fungicide fludioxonil. Ssk2 is the only polymorphic component in the Hog1 MAPK module, including two coding sequence changes between the SSK2 alleles in B3501 and B3502 strains. To further support this finding, the SSK2 allele exchange completely swapped Hog1-related phenotypes between B3501 and B3502 strains. In the serotype A strain H99, disruption of the SSK2 gene dramatically enhanced capsule biosynthesis and mating efficiency, similar to pbs2 and hog1 mutations. Furthermore, ssk2, pbs2, and hog1 mutants are all hypersensitive to a variety of stresses and completely resistant to fludioxonil. Taken together, these findings indicate that Ssk2 is the critical interface protein connecting the two-component system and the Pbs2-Hog1 pathway in C. neoformans.

• Molecules and Cells
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• 제20권3호
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• pp.385-391
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• 2005

As a first step towards identifying genes involving in the signal transduction pathways mediating rice blast resistance, we isolated 3 mutants lines that showed enhanced susceptibility to rice blast KJ105 (91-033) from a T-DNA insertion library of the japonica rice cultivar, Hwayeong. Since none of the susceptible phenotypes co-segregated with the T-DNA insertion we adapted a map-based cloning strategy to isolate the gene(s) responsible for the enhanced susceptibility of the Hwayeong mutants. A genetic mapping population was produced by crossing the resistant wild type Hwayeong with the susceptible cultivar, Nagdong. Chi-square analysis of the $F_2$ segregating population indicated that resistance in Hwayeong was controlled by a single major gene that we tentatively named Pi-hy. Randomly selected susceptible plants in the $F_2$ population were used to build an initial map of Pi-hy. The SSLP marker RM2265 on chromosome 2 was closely linked to resistance. High resolution mapping using 105 $F_2$ plants revealed that the resistance gene was tightly linked, or identical, to Pib, a resistance gene with a nucleotide binding sequence and leucine-rich repeats (NB-LRR) previously isolated. Sequence analysis of the Pib locus amplified from three susceptible mutants revealed lesions within this gene, demonstrating that the Pi-hy gene is Pib. The Pib mutations in 1D-22-10-13, 1D-54-16-8, and 1C-143-16-1 were, respectively, a missense mutation in the conserved NB domain 3, a nonsense mutation in the 5th LRR, and a nonsense mutation in the C terminus following the LRRs that causes a small deletion of the C terminus. These findings provide evidence that NB domain 3 and the C terminus are required for full activity of the plant R gene. They also suggest that alterations of the resistance gene can cause major differences in pathogen specificity by affecting interactions with an avirulence factor.