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.

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.

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.

향미 품종의 방향성 유전

Sang Nag Ahn(安相洛),Kook Hyun Chung(鄭國鉉),Ha Cheol Hong(洪夏鐵),Hae Chune Choi(崔海椿),Huhn Pal Moon(文憲八) 한국육종학회 1996 한국육종학회지 Vol.28 No.1

This study was carried out to elucidate the inheritance of aroma in rice. Aromatic nature was tested with leaves of two aromatic/non-aromatic crosses and six crosses among aromatic cultivars. All F₁ hybrids of non-aromatic cultivar Hwaseongbyeo and aromatic cultivars, Sanghaehyanghyeolla, Miyakaori, Della, Selatus Malam, Manong Balay, Hyangmibyeo 1 and Chokoto were not aromatic and this seemed to indicate the recessive nature of the aroma in all tested rices. F₂ segregation ratio of 3 non-aromatic : 1 aromatic individual suggested that Sanghaehyanghyeolla and Miyakaori each contained a single gene for aroma. The finding that all F₁ hybrids among six aromatic rice cultivars were aromatic suggested that the aroma in Sanghaehyanghyeolla and Miyakaori may be controlled by the same gene known to be in Della and the aroma genes in Manong Balay and Chokoto are also allelic although the number of genes controlling the aroma in these cultivars are not known. No linkage was detected between the aroma gene(fgr) in Sanghaehyanghyeolla and two genetic markers(sug and v-8) located on rice chromosome 8.

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>

QTL Mapping of Grain Quality Traits Using Introgression Lines Carrying <i>Oryza</i> <i> rufipogon</i> Chromosome Segments in <i>Japonica</i> Rice

Yun, Yeo-Tae,Chung, Chong-Tae,Lee, Young-Ju,Na, Han-Jung,Lee, Jae-Chul,Lee, Sun-Gye,Lee, Kwang-Won,Yoon, Young-Hwan,Kang, Ju-Won,Lee, Hyun-Sook,Lee, Jong-Yeol,Ahn, Sang-Nag Springer US 2016 Rice Vol.9 No.-

<P><B>Background</B></P><P>Improved eating quality is a major breeding target in <I>japonica</I> rice due to market demand. Consequently, quantitative trait loci (QTL) for glossiness of cooked rice and amylose content associated with eating quality have received much research focus because of their importance in rice quality.</P><P><B>Results</B></P><P>In this study, QTL associated with 12 grain quality traits were identified using 96 introgression lines (IL) of rice developed from an interspecific cross between the Korean elite <I>O. sativa japonica</I> cultivar ‘Hwaseong’ and <I>O. rufipogon</I> over 7 years. QTL analyses indicated that QTL <I>qDTH6</I> for heading date, detected on chromosome 6 is associated with variance in grain traits. Most QTLs detected in this study clustered near the <I>qDTH6</I> locus on chromosome 6, suggesting the effect of <I>qDTH6. O. rufipogon</I> alleles negatively affected grain quality traits except for a few QTLs, including <I>qGCR9</I> for glossiness of cooked rice on chromosome 9. To characterize the effect of the <I>O. rufipogon</I> locus harboring <I>qGCR9,</I> four lines with a single but different <I>O. rufipogon</I> segment near <I>qGCR9</I> were compared to Hwaseong. Three lines (<I>O. rufipopgon</I> ILs) having <I>O. rufipogon</I> segment between RM242 and RM245 in common showed higher glossiness of cooked rice than Hwaseong and the other line (Hwaseong IL), indicating that <I>qGCR9</I> is located in the 3.4-Mb region between RM242 and RM245. Higher glossiness of cooked rice conferred by the <I>O. rufipogon</I> allele might be associated with protein content considering that three lines had lower protein content than Hwaseong (<I>P</I> < 0.1). These three <I>O. rufipogon</I> ILs showed higher yield than Hwaseong and Hwaseong IL due to increase in spikelets per panicle and grain weight indicating the linkage of <I>qGCR9</I> and yield component QTLs.</P><P><B>Conclusion</B></P><P>The <I>qGCR9</I> locus is of particular interest because of its independence from other undesirable grain quality traits in <I>O. rufipogon</I>. SSR markers linked to <I>qGCR9</I> can be used to develop high-quality <I>japonica</I> lines and offer a starting point for map-based cloning of genes underlying this trait. To our knowledge, this is the first report to map a beneficial QTL for glossiness of cooked rice from a wild rice, <I>O. rufipogon</I>.</P><P><B>Electronic supplementary material</B></P><P>The online version of this article (doi:10.1186/s12284-016-0135-0) contains supplementary material, which is available to authorized users.</P>

Identification of QTL for grain quality traits using introgression lines derived from an interspecific cross in rice

Yeo-Tae Yun,Chong-Tae Chung,Yeong-Ju Lee,Han-Jung Na,Jae-Chul Lee,Kwang-Won Lee,Young-Hwan Yoon,Ju-Won Kang,Hyun-Sook Lee,Sang-Nag Ahn 한국육종학회 2015 한국육종학회 심포지엄 Vol.2015 No.07

96 BC3F5 introgression lines derived from a cross between Hwaseong and O. rufipogon were genotyped with 131 simple sequence repeat (SSR) markers to identify and characterize quantitative traits loci (QTLs) associated with grain quality traits in rice. 96 BC3F5 lines displayed a wide range of variation for days to heading and agronomic traits. Results indicated that one major QTL (qDTH6) on chromosome 6 was associated with significant variation for days to heading. 83 lines without the O. rufipogon segment at qDTH6 were selected and analyzed for grain quality traits. QTL analysis was conducted for two groups, 96 and 83 introgression lines, and a total of 25 QTLs were detected for rice quality traits. 16 QTLs were detected in a group of 93 lines, 11 QTLs detected in a group of 83 lines, and 2 QTLs were commonly identified in both groups. Most of the QTLs detected in this study were located on the same or adjacent regions as those reported by the previous studies, and the wild alleles negatively affected quality traits. In contrast, the wild allele at qGCR9 for the glossiness of cooked rice on chromosome 9 contributed to an increase in glossiness which is positively correlated with rice eating quality. Three ILs with the wild allele at qGCR9 displayed better eating quality than the recurrent parent, Hwaseong. To confirm the effect of qGCR9, high density mapping of the qGCR9 with a series of NILs will be conducted.

MFC 기반 음성구동 수치지도정보 검색시스템의 구현

조명희(Myung Hee Jo),김낙철(Nag Cheol Kim),김태수(Tae Soo Kim),정현열(Hyun Yeol Chung) 한국지리정보학회 2000 한국지리정보학회지 Vol.3 No.1

지리정보시스템(GIS)을 이용한 지도정보의 검색과 공간분석에 있어서 마우스나 키보드를 이용할 경우 수 차례의 동일한 작업을 반복하여 대상지역의 범위를 지정하고 있다. 본 연구에서는 이와 같은 반복작업을 제거하여 신속한 정보검색이 가능하도록 음성인식 기능을 이용한 검색시스템을 제안하고 이를 개인용 컴퓨터상에서 구현하였다. 특히 시스템의 실용화를 위한 검색화면 제어에 있어서는 OLE(object linking embedding)기법과 MFC(Microsof In retrieving and analyzing digital map information using mouse or key strokes, it needs several times of repeated mouse operation for designating the range of study area. In this study, we proposed a voice activated map information retrieval system for e

Aureobasidium pullulans 에 의한 Pullulans 생산에 관한 연구

임무현,손흥수,정낙현,양한철 ( Moo Hyun Yim,Heung Soo Son,Nag Hyun Chung,Han Chul Yang ) 한국미생물생명공학회 1984 한국미생물·생명공학회지 Vol.12 No.3