This study aimed to indentify single nucleotide polymorphisms (SNPs) in exon region of the glycerol-3-phosphate dehydrogenase 1 (GPD1) gene and to evaluate their associations with meat yield and quality traits in Hanwoo (Korean cattle). Two SNP markers, g.2766C>T and g.5105A>G were identified in the exons 5 and 8, respectively. Genotyping of the two SNPs was carried out using PCR-RFLP analysis in 309 Hanwoo steers to evaluate their associations with meat yield and quality traits. As a result, g.2766C>T in exon 5 was significantly associated with carcass weight (CW) and marbling score (MS). Animals with the CC genotype of g.2766C>T had heavier CW than those with the CA or AA genotype. Animals with the CC genotype of g.2766C>T also had higher MS than those with the CA or AA genotype. Additive effect was also observed with CW and MS traits. We constructed haplotypes by linkage disequilibrium analysis and analyzed association between haplotypes and meat yield and quality traits. Haplotype of GPD1 gene was associated with CW. As a result, animals with CA haplotype had heavier CW than TG haplotype. These findings suggest that the SNPs of bovine GPD1 gene may be a useful molecular marker for selection of meat yield and quality traits in Hanwoo.

This study was conducted for SNPs in the 5'-regions of estrogen receptor-α(ESR-α), and association with calving interval (CI), service per conception (SPC) and 305 days milk yield in Hanwoo and Holstein dairy cattle. The genet-ic improvement was incurred low reproduction performance. The objective of this study was to investigate connec-tions between single nucleotide polymorphisms (SNP) of Estrogen receptor-α (ESR-α) with reproduction performance (calving interval, service per conception, and 305 d milk yield) in Hanwoo and Holstein dairy cattle. Hanwoo and Holstein blood samples were collected from 183 and 124 dam of breeding farms and DNA was extracted. Primer design was based on NCBI GenBank (Accession No. AY340579). The PCR-RFLP method with Bgl I was used to ge-notype the cattle. The result showed two variants of the ESR-α gene. The Bgl I cut the 492 bp amplification pro- duct into 322 bp and 170 bp fragments for allele G, while allele A remained uncut, resulting in two restriction frag-ments for homozygote G/G and three fragments for heterozygote A/G. We found two of different genotypes in the-se breeds, A/G and G/G. In Hanwoo, the A/G genotype frequency was 0.13, and G/G was 0.87. The CI of A/G was 382.18±10.03 days, and G/G was 381.69±5.22 days. The SPC of A/G was 1.62±0.16, and G/G was 1.32±0.04. While CI showed no significance difference, SPC exhibited significant difference (p<0.05). In Holstein cattle, the frequency of genotype A/G was 0.02 and G/G was 0.98. The 305 days milk yield of A/G was 7,253.00±936.00 kg and of G/G was 8,747.51±204.88 kg, showing no significant difference.

MYC (v-myelocytomatosis viral oncogene homologue) is a regulator gene that encodes for a nuclear phosphoprotein. Porcine MYC gene was mapped on chromosome SSC 4p13 and is associated with a variety of functions such as cell proliferation and cell growth. MYC expression is coupled to a multitude of physiological processes and is regulated by hormones, growth factors, cytokines, lymphokines, nutritional status, development and differentiation. MYC is also involved in myogenesis, muscle hyperplasia and adipogenesis. In this study, we investigated SNPs in MYC gene and their association with economic traits in Duroc, Landrace and Yorkshire populations. We detected a single point mutation in exon 3 of porcine MYC gene as a change of T to C at 906 base (amino acid position 302, nonsynomous mutation of alanine) in MYC-N domain. MYC mutation (T906C) was significantly associated with age at 90 kg in these breeds, signifying that this mutation can serve as a selection marker for growth traits in pigs.

Myopalladin (MYPN) is an important expression gene associated with regulation of Z-line structure in muscle and maintains sarcomeric integrity. In this study, we investigated the association between MYPN A1795G SNP (single nucleotide polymorphism) and carcass traits (LMA, longissimus muscle area; CW, carcass weight; BF, backfat thickness; MS, marbling score) in Korean cattle. The MYPN A1795G SNP was genotyped in 212 steers and analyzed the associations with carcass traits by PCR-RFLP (Restriction fragment length polymorphism) method. The allele frequencies were 0.566 for G allele and 0.434 for A allele. And the genotype frequencies of GG, GA, and AA genotype were 32.1%, 49%, and 18.9%, respectively. Association analysis indicated that the A1795G SNP of MYPN gene showed a significant association with LMA (p<0.05). The steers with GG genotype had higher LMA than those with the genotypes AA. But no significant associations were observed in other carcass traits (CW, BF, MS). The steers with the GG genotype showed higher CW and BF than those with the genotypes AA and GA. These results suggest that the A1795G SNP of the MYPN gene is associated with LMA and may be useful for candidate marker-assisted selection to increase the levels of LMA in Korean cattle.

Leaf mold disease in tomato (Solanum lycopersicum) is caused by Cladosporium fulvum, a fungal leaf pathogen. One of effective ways to control leaf mold is to breed disease-resistant tomato cultivars. Cf-4 and Cf-9 resistance (R) genes encode proteins that carry a leucine rich repeat domain and are located in plasma membrane. They trigger hypersensitive response following recognition of corresponding Avr4 and Avr9 proteins of C. fulvum, respectively. Cf-4 and Cf-9 genes are originated from wild tomato species S. habrochaites and S. pimpinellifolium and have been introgressed into commercial tomato cultivars. These two highly homologous orthologs exist as a cluster with four highly homologous paralogs. Due to this reason, development of genetic markers to distinguish these two functional R genes from their orthologs and paralogs is difficult. In this study, we tried to develop single-nucleotide polymorphism (SNP) markers to select tomato cultivars carrying resistant Cf-9 genotype. The genomic sequences of resistant Cf-4 and Cf-9 alleles, susceptible cf-9 alleles, and their paralogs were obtained from the GenBank database, and two functional SNPs causing non-synonymous substitution were found among them. Based on two SNPs, the Cf-9_2-SNP-F/R primer set for high resolution melting (HRM) analysis was developed. HRM analysis with this primer set could successfully distinguish tomato cultivars carrying resistant Cf-9 allele among 30 commercial tomato cultivars, which were characterized with the gene-based marker. These indicate that the SNP marker developed in this study is useful to trace Cf-9 genotype efficiently in marker-assisted selection in tomato.

Tomato spotted wilt virus (TSWV) causes one of the most destructive viral diseases that threaten tomato (Solanum lycopersicum) worldwide. So far, eight TSWV resistance genes, Sw1a, Sw1b, sw2, sw3, sw4, Sw-5b, Sw-6, and Sw-7 have been identified and Sw-5b has been incorporated into tomato for prevention of TSWV. The objectives of this research are first to discover single nucleotide polymorphisms (SNPs) in Sw-5 alleles and then to develop SNP markers to distinguish resistant genotypes against TSWV for marker-assisted breeding in tomato. First, DNA sequences of Sw-5b alleles from both resistant and susceptible cultivars amplified using known Sw-5 gene-based marker was analyzed. The single functional SNP (G→A) was detected as non-synonymous substitution because this SNP causes change of arginine (Arg599) to glutamine (Gln599). Next, the primer pair for high resolution melting analysis (HRM) was designed around this SNP. To determine accuracy of this SNP marker to distinguish resistant Sw-5b genotypes against TSWV, genotypes of 32 commercial tomato cultivars were checked. The newly developed SNP marker could select six cultivars carrying resistant Sw-5b genotype, which was 100% correlated with genotypes based on the gene-based marker. These results indicate that the SNP maker developed in this study could be useful for better tracking resistance to TSWV in tomato breeding.

Blackleg disease caused by Leptosphaeria maculans, is the most devastating disease of Brassica germplam worldwide that causes million tonnes of crop losses per year throughout the world. To date, a total of 12 race-specific resistance genes of Brassica napus to L. maculans have been reported but linkage mapping analysis reveals that all of those loci are located in A genome i.e., in B. rapa chromosomes. B. oleracea has high ancestral synteny with B. rapa through their evolution. We believe that presence of qualitative resistance is possible in B. oleracea germplasm. The present study was therefore planned to find out any race-specific qualitative resistance gene present in C genome of B. oleracea. A total of 16 microsatellite markers were used which are linked to seven different Rlm and Lep genes of B. napus to screen 32 inbred lines of cabbage. Primers were designed based on homology assessment in corresponding nucleotide sequence available in Bolbase (a B. oleracea genome database, http://www.ocri-genomics.org/bolbase/index.html), located in B. oleracea scaffolds/chromosomes. Out of 16 SSR markers, 13 were found polymorphic which indicates possible existence of resistant genes in cabbage lines. The inbred lines are then assessed against two L. maculans stains with known avirulent genes. Some inbred lines were hypersensitive against gene-specific virulent strains of L. maculans that confirmed existence of Rlm1, Rlm2, Rlm4, LepR3 and LepR4 in the cabbage lines. In this way we were able to select out resistant and susceptible lines against each resistant gene. The gene-specific polymorphic SSR marker regions were cloned and sequenced and candidate SNPs were identified for confirmation of their functionality.

Sucrose synthase 3 which is a third active gene present in rice, is localized predominantly in rice endosperm. This sucrose synthase 3 may play an important role in the starch filling in the milky stage rice seed, probably involving in the starch physicochemical properties. As the genetic diversity at this locus is little informed, forty three rice consisting of japonica, indica and Oryza rufipogon were targeted to amplify full sequence of sucrose synthase 3 to examine the frequency and distribution of nucleotide polymorphism. Total of 755 all sequence variants detected, 491 single nucleotide polymorphisms (SNPs) and 264 indels were successfully identified in 7618 bp of sequence containing the sucrose synthase 3 transcript, promoter and 3' non-transcribed region. The frequency of nucleotide changes and indels were high, on average one polymorphism per 15.5 bp and one indel per 28.9 bp with 11 sequence-based haplotypes distinguishable among the varieties and lines. Both the frequency of nucleotide changes and indels were frequent in non-coding region, but rare in coding region. Sequencing a polymorphism region in the promoter showed one base change on one of cis-element from T (CATGCATA to A (CATGCACA) that might implicate in seed specificity. The presence of a high number of haplotype shared by a few varieties indicated a little information on linkage disequilibrium.

Japonica rice cultivars exhibit high susceptibility to BB disease due to genetic vulnerability in Korea. Korean Japonica rice cultivars mainly posses the genes, Xa1 and Xa3 for BB resistance. These resistance genes are becoming susceptible to K3a, new races of BB, resulting in the breakdown of resistance in high yielding Japonica cultivars. It is imperative to look for novel R-genes for improvement of japonica rice resistant to BB races. This study was carried out to conform useful single gene resistant to 24 BB isolates (including K3a, HB01009) breaking down Xa3 gene. Cultivars and near-isogenic lines (NILs) carrying Xa1, Xa2, xa8, Xa10, Xa11, xa13 genes were susceptible to 24 isolates, whereas IRBB4 carrying Xa4 gene was moderate resistance. IRBB5 and IRBB21 having xa5 and Xa21 genes, respectively, expressed resistance to these isolates. IRBB7 having Xa7 gene showed resistance response to 24 BB isolates, whereas JBB-107 carrying Xa7 gene was susceptible to 10 BB isolates and moderate resistant to 14 BB isolates. Xa7 gene showed different resistance response according to genetic background of used recurrent parent. With these findings, Xa4, xa5, and Xa21 would be the most prospective genes to 24 isolates used in screening.

Ferritin light heavy chain (FLHC) gene는 일부 중금속과 결합, 저장 및 운반하여 무독화 시킬 수 있는 것으로 알려져 있다. Fe 관련 유전자인 FLHC유전자를 식물 발현용 promoter인 35S promoter와 Tnos를 사용하여 식물 형질전환용 vector를 재조합하였다. 식물세포형질전환용 binary vector는 상기 cassette vector가 조립이 매우 양호하며 border sequence를 가지고 있는 pRD400 binary vector를 사용하여 최종적으로 가나마이신 내성 유전자 (NPT II gene)와 tadpole ferritin heavy chain gene 및 human ferritin light chain gene를 함유하고 있는 binary vector를 재조합하였다. Binary vector의 아그로박테리움에 도입은 triparental mating 방법에 의하여 수행하여 AB배지 및 가나마이신 함유 배지에서 disarmed Ti-vector를 가지고 있는 Agrobacterium tumefaciens MP90/FLHC을 선발하였다. FLHC 유전자 도입된 식물형질전환용 binary vector를 이용하여 형질전환방법을 변형하여 많은 embryo를 유도하였으며 유도된 embryo들은 GA 10mg/L가 첨가된 배지에 지상부를 유도하였다. 형질전환체식물체의 정상적인 생장을 유도하기 위해 최적의 배양조건을 조사하였던 바, 비교적 1/3 MS배지에서 뿌리의 생장과 지상부의 생장이 균일하게 생장하는 경향을 보였으며, 뿌리와 줄기가 잘 발달된 약 7cm의 유식물체를 대량으로 증식하여, 모래와 흙이 1:1로 혼합된 토양에 옮겼다.

Ginseng(Panax ginseng C.A. Meyer) is a perennial herbaceous plant which grows very slowly. It takes about 3 to 4 years from seeding to collecting the ripe seeds and the ginseng propagation is very difficult. and so, it is very difficult to breed ginseng plant. Ginseng tissue culture was started from at 1960, and ginseng commercial product by in vitro callus culture was saled, however upto now, regenerants were not planted to soil normally. Recently, plant genetic engineering to produce transgenic plants by introducing useful genes has been advanced greatly. In a present paper, transformation of ginseng plants was achieved by co-cultivation with Agrobacterium harboring the binary vector coding Proteinase-II gene, which confer resistant or tolerant to insect pests, The binary vector for transformation was constructed with disarmed Ti-plasmid and with double 35S promoter. The NPT II gene and introduced genes of the transgenic ginseng plants were successfully identified by the PCR. Especially the transgenic ginseng plants were regenerated using new techniques such as repetitive single somatic embryogenesis.