Testicular Expression of Steroidogenic Enzyme Genes Is Related to a Transient Increase in Serum 19-nortestosterone during Neonatal Development in Pigs

Choi, Nag-Jin,Hyun, Jin Hee,Choi, Jae Min,Lee, Eun Ju,Cho, Kyung Hyun,Kim, Yunje,Chang, Jongsoo,Chung, Il Byung,Chung, Chung Soo,Choi, Inho Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.12

Cytochrome P450 aromatase is responsible for the biosynthesis of estrogen. It is also responsible for the endogenous production of 19-nortestosterone (nandrolone), an anabolic androgen unique to pigs. Plasma concentrations of 19-nortestosterone are highest between two and four weeks after birth in male pigs. In the present study, the physiology of 19-nortestosterone was investigated by measuring the mRNA levels of steroidogenic enzymes, estrogen receptors and androgen receptor in the tissues of growing pigs. The expression of aromatase, 17${\alpha}$-hydroxylase and 3${\beta}$-hydroxysteroid dehydrogenase in the testes of male piglets increased between birth and two weeks of age, and then decreased progressively. Similar developmental expressional patterns were observed for 17${\alpha}$-hydroxylase and 3${\beta}$-hydroxysteroid dehydrogenase in the ovaries of female piglets, but without significant aromatase expression. The major form of aromatase expressed in the testes of piglets was identified as type I. Expression of estrogen receptor-${\alpha}$ and -${\beta}$and androgen receptor genes was also detected in both testes and ovaries. A transient elevation of androgen receptor mRNA in male piglets at two weeks of age was also observed in testes. Significant expression of the androgen receptor gene, but not of estrogen receptor-${\alpha}$ and -${\beta}$ genes, was also demonstrated in adipose tissue and muscle. We conclude that the observed increase in the testicular expression of aromatase in male pigs could account for the production of large amounts of 19-nortestosterone at between two and four weeks of age in males. Androgen receptor and 19-nortestosterone appeared to be important for testicular development and might contribute to sexual dimorphism in body composition and muscle development in juvenile pigs.

Genetic Diversity and Classification of Korean Weedy Rice based on RAPD Markers

Nam Jin Chung,Sang Nag Ahn 한국육종학회 2005 한국육종학회지 Vol.37 No.3

Identification of Molecular Markers for Photoblastism in Weedy Rice

Hyun Sook Lee,Sang Nag Ahn,Kazuhiro Sasaki,Nam Jin Chung,Kwan Sam Choi,Tadashi Sato 한국육종학회 2010 한국육종학회지 Vol.42 No.2

The objective of this study was to map gene/QTL for photoblastism in a weedy rice (photoblastic rice: PBR) using DNA markers. Light-induced effect on germination of seeds was compared among three accessions (Oryza sativa L.), PBR, Milyang 23 and Ilpum. Results showed that PBR seeds started to show photoblastism during seed development, different from Ilpum and Milyang 23. Frequency distribution of germination in the F4 lines from crosses between Ilpum and PBR and, Milyang 23 and PBR revealed bimodal distributions suggesting that photoblastism was controlled by a few genes. Bulked segregant analysis using F4 populations derived from the above two crosses was conducted to identify gene/QTL for photoblastism. Two QTL were identified on chromosomes 1 and 12 explaining 11.2 and 12.8% of the phenotypic variance, respectively. Two QTL were further mapped between two SSR markers, RM8260 and RM246 on chromosome 1, and between RM270 and 1103 on chromosome 12. It is noteworthy that two QTL for photoblastism were colocalized with the QTL for seed dormancy reported in the previous QTL studies. The clustering of two genes for photoblastism and dormancy possibly indicates that these regions constitute rice phytochrome gene clusters related to germination. Because PBR has a low degree of dormancy, a pleiotropic effect of a single gene controlling dormancy and photoblastism can be ruled out. The linked markers will provide the foundation for positional cloning of the gene.

반추기축영양 : 섬유질 배합사료 원료로서 맥주박, 비지박 및 볏짚이 한우 거세우의 사양성적, 혈액성상 및 도체특성에 미치는 영향

장선식 ( Sun Sik Chang ),권혁진 ( Hyuk Jin Kwon ),이상민 ( Sang Min Lee ),조영무 ( Young Moo Cho ),정기용 ( Ki Yong Chung ),최낙진 ( Nag Jin Choi ),이성실 ( Sung Sill Lee ) 한국동물자원과학회(구 한국축산학회) 2013 한국축산학회지 Vol.55 No.1

본 연구는 맥주박, 비지박 및 볏짚을 각각 이용하여 배합한 TMR을 한우 거세우에게 급여하였을 때 사양성적, 혈액성상 및 도체특성을 구명하고자 수행되었다. 시험구는 6개월령 한우 거세우 24두(평균체중 168kg)를 배합사료 볏짚 분리급여구(T1), 맥주박 첨가 TMR 급여구(T2), 비지박 첨가 TMR 급여구(T3) 및 볏짚첨가 TMR 급여구(T4)에 각각 6두씩 완전임의 배치하여 총 22개월간 사양시험을 실시하여 28개월령에 도축하였다. 시험결과에서 체중은 육성기에서 비육전기까지 처리구들간 유의적인 차이는 없었다. 하지만, 종료시 체중에서 T4 처리구가 T2 처리구에 비해 유의적으로 높았다. 일당증체량은 육성기 및 비육중기에서 TMR 급여구가 T1에 비해 유의적으로 높았지만(p<0.05), 전체평균에서는 차이가 없었다. 건물섭취량은 TMR 급여구(T2, T3, T4)에서 높은 경향을 나타내었다. 사료요구율은 T2 처리구에 비해 T4 처리구가 유의적으로 낮았다(p<0.05). 육량특성에서 도체중은 T1, T2, T3 및 T4 처리구에서 각각 389.0, 368.4 387.5 및 384.3kg이었다. 등지방두께, 등심단면적 및 육량지수는 처리구들간 유의적 차이는 없었다. 육질특성에서 육색, 지방색, 조직감 및 성숙도에서는 처리구간 유의적인 차이가 있었으나, 근내지방도와 육질 1+ 등급 이상출현율에서는 T2와 T3 처리구가 다른 처리구에 비해 높았다. 따라서 본 연구의 결과 맥주박과 비지박을 이용한 TMR 사료는 한우 거세우의 발육 및 도체특성에 있어 적절한 것으로 나타났다. This study was conducted to investigate the dietary effect of total mixed rations(TMR) containing brewers grain, soybean curd and rice straw, respectively, on growth performance and carcass characteristics of Hanwoo steers. Twenty four Hanwoo steers (average body weight 168 kg) in 6 months age were randomly allocated to 4 experimental groups, which contained 6 animals per group during 22-months feeding trial. The treatment was composed of the group fed concentrate and rice straw separately(T1), the group fed TMR containing brewers grain(T2), the group fed TMR containing soybean curd(T3) and the group fed TMR containing rice straw(T4). Body weight(BW) was not different among treatment groups during the growing and middle fattening period. However, it was significantly greater in T4 group than in T2 group on the final BW(p<0.05). Average daily gain was significantly greater in TMR groups compared to T1 group on the growing and late fattening(p<0.05). However, it was not different in total average. Dry matter intake tended to be increased in TMR groups. The feed conversion ratio was significantly lower in T4 group compare to T2 group(p<0.05). According to the yield traits, carcass weight of T1, T2, T3 and T4 were 389.0, 368.4, 387.5 and 384.3 kg, respectively. The back fat thickness, rib-eye area, and yield index were not different among the groups. Meat color, fat color, texture and maturity were not significantly different among groups. However, marbling score and appearance rate of meat quality grade of over 1+ were greater in T2 and T3 groups compare to other groups. Therefore, these results indicated that TMR with brewers grain and soybean curd may be ameliorated the growth performance and carcass characteristics of Hanwoo steers.

Naphthoquinone -1,2- Diazaide - Sulfonyl 기 치환 Polysiloxane 의 합성과 그 감광특성

강두환,정낙진 ( Doo Whan Kang,Nag Jin Chung ) 한국공업화학회 1991 공업화학 Vol.2 No.4

Hexamethylcyclotrisiloxane (D_3), tetramethylcyclotetrasiloxane (TMCTS)을 공중합 시켜 Si-H 결합을 함유한 polysiloxane 공중합체를 합성하고 allylamine과 반응시켜 amino기를 도입시킨 후 naphthoquinone-1,2-diazide-5-sulfonyl chlorde 와 반응시켜 naphthoquinone-1,2-diazide-5-sulfonyl 기가 도입된 polysiloxane 을 합성하였다. 생성 공중합체의 열적특성을 측정한 결과, 열분해온도는 360∼450 ℃ 정도였으며 또한 감광특성은 backbone 수지의 분자량이나 증감제의 종류에 따라 영향을 받았다. Sensitivity는 50∼120 mJ/㎠였고 contrast(γ)는 1.4∼2.1였으며 backbone 수지의 분자량이 증가함에 따라 약간 감소하였다. Polysiloxane copolymers were prepared by copolymerizing hexamethylcyclotrisiloxane with tetramethylcyclotetrasiloxane, and then reacted with allyamine. Copolymers containing naphthoquinone-1,2-diazide-5-sulfonyl group were synthesized by reacting naphthoquinone-1,2-diazide-5-sulfonyl chloride with siloxane copolymers having amino group. Thermal decomposition temperatures of copolymers were 360∼450 ℃, and photosensitive characteristics were dependent on the molecular weights of backbone resins and sensitizers. Sensitivity of copolymers was 50-120 mJ/㎠ and contrast (γ) was 1.4∼2.1.

Identification of Molecular Markers for Mesocotyl Elongation in Weedy Rice

Hyun-Sook Lee,Ju-Won Kang,Nam-Jin Chung,Kwan-Sam Choi,Sang-Nag Ahn 한국육종학회 2012 한국육종학회지 Vol.44 No.3

In direct-seeding cultivation of rice, the emergence and establishment of seedlings are important for determining the actual yield. These traits depend principally upon elongation of both the mesocotyl and coleoptile. Mesocotyl elongation in rice is controlled by several genetic factors and is also affected by environmental factors. In this study, we mapped QTL for mesocotyl elongation using F8 lines from a cross between the cultivated rice, Ilpumbyeo and a weedy rice, PBR. One of the Korean weedy rice, PBR showed the long mesocotyl length than that of cultivars, Ilpumebyeo under soil and agar media conditions. This weedy rice showed long mesocotyl than the elite japonica cultivars. After a phenotyping of 150 F7 lines for mesocotyl length, a subset of 20 lines selected from the two extreme phenotypic tails was used for the bulked segregant analysis. Two QTL were identified on chromosomes 1 and 3. These two QTL were confirmed using 120 F8 lines. Two QTL, qMel-1 and qMel-3 on chromosomes 1 and 3 accounted for 37.3% and 6.5% of the phenotypic variance, respectively. The PBR alleles were associated with an increase in mesocotyl elongation at both loci. It is noteworthy that two QTL for mesocotyl elongation were colocalized with the QTL for mesocotyl length reported in the previous QTL reports. These QTLs can be introgressed into cultivar background using marker assisted backcrossing in an effort to enhance the level of mesocotyl elongation.

Effects of Dietary Energy Intake Levels on Growth Performance and Body Composition of Finishing Barrows and Gilts

Cho, Sung Back,Kim, Dong Woon,Baek, Kyung Hoon,Lee, Byong Seak,Chung, Il Byung,Chung, Wan Tae,Choi, Nag-Jin Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.10

This study was conducted to investigate the effects of different energy intake on physical and chemical composition in body fractions, growth performance and meat characteristics of finishing barrows and gilts. A total of twenty six crossbred (Landrace$\times$Yorkshire) consisting of 16 barrows and 13 gilts were used in this study. The animals were allocated by sex to two treatments to form a $2\times2$ factorial arrangement. The respective factors were sex (barrow and gilt) and dietary energy intake (1.8 and 3.0 times energy for maintenance). Pigs were kept in individual pens and had ad libitum access to feed and water from the start of the experiment at $52.4{\pm}1.9kg$ until they reached $109.9{\pm}4.4kg$ live weight. The growth performance, physical composition and meat characteristics of finishing pigs were not greatly affected by the sex. However, higher fat tissue weight in the carcass was observed in barrows compared with gilts (p<0.05). Higher proportions of water and protein (p<0.05), and lower lipid proportion (p<0.01) in the empty body and carcass were observed in gilts compared with barrows, while protein proportion in lean tissue was not affected by the sex. In fat tissue, only protein proportion was higher in gilts compared with barrows (p<0.05). Although, growth performance, physical and chemical compositions in body fractions were greatly affected, final body or carcass weight was partly affected by the energy intake In addition, loin characteristics such as shear force and loin eye area were partly influenced by energy intake levels. Therefore, the present results showed that growth performance and meat characteristics were not influenced but chemical body composition was greatly influenced by the sex. Growth performance, physical and chemical compositions in body fractions were greatly affected, whereas meat characteristics were partly affected by the energy intake levels.

Assessment of molecular genetic diversity and population structure of sesame (<i>Sesamum indicum</i> L.) core collection accessions using simple sequence repeat markers

Park, Jong-Hyun,Suresh, Sundan,Cho, Gyu-Taek,Choi, Nag-Gor,Baek, Hyung-Jin,Lee, Chul-Won,Chung, Jong-Wook Cambridge University Press 2014 Plant genetic resources Vol.12 No.1

<P>Sesame (<I>Sesamum indicum</I> L.) is one of the oldest oil crops and is widely cultivated in Asia and Africa. The aim of this study was to assess the genetic diversity, phylogenetic relationships and population structure of 277 sesame core collection accessions collected from 15 countries in four different continents. A total of 158 alleles were detected among the sesame accessions, with the number varying from 3 to 25 alleles per locus and an average of 11.3. Polymorphism information content values ranged from 0.34 to 0.84, with an average of 0.568. These values indicated a high genetic diversity at 14 loci both among and within the populations. Of these, 44 genotype-specific alleles were identified in 12 of the 14 polymorphic simple sequence repeat markers. The core collection preserved a much higher level of genetic variation. Therefore, 10.1% was selected as the best sampling percentage from the whole collection when constructing the core collection. The 277 core collection accessions formed four robust clusters in the unweighted pair group method and the arithmetic averages (UPGMA) dendrogram, although the clustering did not indicate any clear division among the sesame accessions based on their geographical locations. Similar patterns were obtained using model-based structure analysis and country-based dendrograms, as some accessions situated geographically far apart were grouped together in the same cluster. The results of these analyses will increase our understanding of the genotype-specific alleles, genetic diversity and population structure of core collections, and the information can be used for the development of a future breeding strategy to improve sesame yield.</P>

High-density mapping of quantitative trait loci for grain-weight and spikelet number in rice

Kim, Dong-Min,Lee, Hyun-Sook,Kwon, Soo-Jin,Fabreag, Mark Edward,Kang, Ju-Won,Yun, Yeo-Tae,Chung, Chong-Tae,Ahn, Sang-Nag Springer New York 2014 Rice Vol.7 No.-

<P><B>Background</B></P><P>High grain yield is one of the most important traits requiring improvement in rice breeding programs. Consequently, the genetic basis of spikelets per panicle (SPP) and grain weight (TGW) have received much research focus because of their importance in rice yield.</P><P><B>Results</B></P><P>In this study, IL28, which is a near isogenic line (NIL) developed by introgressing chromosomal segments of the cultivar ‘Moroberekan’ into the cultivar ‘Ilpumbyeo’, showed a significant increase in the number of spikelets per panicle (SPP) and 1,000-grain weight (TGW) compared to the recurrent parent, Ilpumbyeo. Quantitative trait locus (QTL) analysis in 243 F2 plants derived from a cross between IL28 and Ilpumbyeo indicated that both <I>qSPP6</I> and <I>qTGW6</I> are located in the interval RM3430–RM20580. Following substitution mapping with 50 F<SUB>3:4:5</SUB> lines, <I>qSPP6</I> was mapped to a 429-kb interval between RM20521 and InDel-1, while <I>qTGW6</I> was mapped to a 37.85-kb interval between InDel-1 and SNP--3 based on the <I>japonica</I> genome sequence. This result indicates that <I>qSPP6</I> and <I>qTGW6</I> are different genes. Yield trials with substitution lines indicated that lines harboring the homozygous Moroberekan segment at both the <I>qSPP6</I> and <I>qTGW6</I> region showed significantly higher grain yield than Ilpumbyeo.</P><P><B>Conclusion</B></P><P>Because the Moroberekan alleles for SPP and TGW have been shown to be beneficial in the genetic background of Ilpumbyeo, both the <I>qSPP6</I> and <I>qTGW6</I> alleles might prove valuable in improving rice yields. Closely linked SSR markers are expected to facilitate the cloning of genes that underlie these QTLs, as well as with marker-assisted selection for variation in SPP and TGW in rice breeding programs.</P><P><B>Electronic supplementary material</B></P><P>The online version of this article (doi:10.1186/s12284-014-0014-5) contains supplementary material, which is available to authorized users.</P>

Reduction of a grid moiré pattern by integrating a carbon-interspaced high precision x-ray grid with a digital radiographic detector : Reduction of a grid moiré pattern

Yoon, Jai-Woong,Park, Young-Guk,Park, Chun-Joo,Kim, Do-Il,Lee, Jin-Ho,Chung, Nag-Kun,Choe, Bo-Young,Suh, Tae-Suk,Lee, Hyoung-Koo Published for the American Association of Physicis 2007 Medical physics Vol.34 No.11

<P>The stationary grid commonly used with a digital x-ray detector causes a moiré interference pattern due to the inadequate sampling of the grid shadows by the detector pixels. There are limitations with the previous methods used to remove the moiré such as imperfect electromagnetic interference shielding and the loss of image information. A new method is proposed for removing the moiré pattern by integrating a carbon-interspaced high precision x-ray grid with high grid line uniformity with the detector for frequency matching. The grid was aligned to the detector by translating and rotating the x-ray grid with respect to the detector using microcontrolled alignment mechanism. The gap between the grid and the detector surface was adjusted with micrometer precision to precisely match the projected grid line pitch to the detector pixel pitch. Considering the magnification of the grid shadows on the detector plane, the grids were manufactured such that the grid line frequency was slightly higher than the detector sampling frequency. This study examined the factors that affect the moiré pattern, particularly the line frequency and displacement. The frequency of the moiré pattern was found to be sensitive to the angular displacement of the grid with respect to the detector while the horizontal translation alters the phase but not the moiré frequency. The frequency of the moiré pattern also decreased with decreasing difference in frequency between the grid and the detector, and a moiré-free image was produced after complete matching for a given source to detector distance. The image quality factors including the contrast, signal-to-noise ratio and uniformity in the images with and without the moiré pattern were investigated.</P>