The olive flounder (Paralichthys olivaceus) is one of the most widely cultured flatfish in Korea and Japan. During development, in a process known as metamorphosis, this fish reorients itself to lie on one side, the body flattens, and the eye migrates to the other side of the body. However, few studies have focused on molecule regulation mechanism of eye development in olive flounder. To reveal the molecular mechanism of eye development, we performed the studies on identification of genes expressed in the eye of olive flounder using EST and RT-PCR strategy. A total of 270 ESTs were sequenced, and 178 (65.9%) clones were identified as known genes and 92 (34.1%) as unknown genes. Among the 178 EST clones, 29 (16.3%) clones were representing 9 unique genes identified as homologous to the previously reported olive flounder ESTs, 131 (73.6%) clones representing 107 unique genes were identified as orthologs of known genes from other organisms. We also identified a kind of eye development associated proteins, indicating EST as a powerful method for identifying eye development-related genes of fish as well as identifying novel genes. Further functional studies on these genes will provide more information on molecule regulation mechanism of eye development in olive flounder.

Cinnamyl alcohol dehydrogenase (CAD, EC 1.1.1.95), catalyzes the reduction of hydroxycinnamaldehydes to give hydroxycinnamyl alcohols, or "monolignols," the monomeric precursors of lignin. Lignins are important components of cell walls and lignified secondary cell walls play crucial roles in long distance transport of water and nutrients during plant growth and development and in plant defense against biotic and abiotic stresses. Here a cDNA clone containing a CAD gene, named as PgCAD, was isolated from a commercial medicinal plant Panax ginseng. PgCAD is predicted to encode a precursor protein of 177 amino acid residues, and its sequence shares high homology with a number of other plant CADS. The expression of PgCAD in adventitious roots and hairy roots of P. ginseng was analyzed using reverse transcriptase (RT)-PCR under various abiotic stresses such as salt, salicylic acid, wounding and chilling treatment that triggered a significant induction of PgCAD at different time points within 2-48 h post-treatment. This study revealed that PgCAD may help the plants to survive against various abiotic stresses.

The full-length cDNA encoding Perilla frutescens limonene synthase (PFLS) (603 amino acids, GenBank accession no. D49368) was cloned. To elucidate the role of PFLS in gene regulation, we transiently transformed full-length PFLS into tobacco plants. PFLS mRNA was first detected in the intact leaves of the plants at 6 h, and the LS transcript level increased after 12 h in leaves treated with oxidative stress-related chemicals. The transient overexpression of PFLS resulted in increased transcription of NbPR1 and NbSIP in Nicotiana benthamiana leaves. Thus, our result confirmed that the infiltration of PFLS gene act as a transcriptional regulator of NbPR1 or NbSIP genes in the tobacco.

We isolated two low temperature-inducible cDNAs designated as MLT5 and MLT31 from mungbean by subtractive suppression hybridization method. By rapid amplification of cDNA end technique, the full-length cDNAs designated MLT5 and MLT31 were obtained. The full-length cDNA of MLT5 contains an open reading frame of 324 nucleotides coding for 107 amino acids. The full-length cDNA of MLT31 contains an open reading frame of 444 nucleotides in length and capable of specifying a 16.5-kDa protein of 148 amino acids (aa) with an isoelectric point of 7.72. RNA expression of MLT5 was strongly induced by low temperature in the early time and also by wounding, NaCl and ABA. MLT31 mRNA was induced by NaCl and ABA but not by wounding and low temperature stress. MLT5 encodes a protein of unknown function, of which targeting site is predicted to be chloroplast membrane protein. To examine the localization of MLT5, MLT5-GFP was expressed in tobacco cells. It was shown that MLT5-GFP was localized to surface of chloroplast in tobacco cell. To examine the function of MLT31, MLT31 was expressed in Escherichia coli as His-fusion protein. Purified MLT31-His recombinant protein will be tested for ubiquitination activity in vitro. In addition, for the in vivo functional analysis of MLT31, MLT31 will be expressed in yeast ubc9 knock-out mutant. We propose that MLT5 and MLT31 play an important role in signal pathway of abiotic stress in plants.

We isolated wound-inducible genes using suppression subtractive hybridization (SSH) method and were able to obtain to clone W3 gene encoding dnaJ like protein. The full-length cDNA of W3 is 689 bp with an open reading frame (ORF) consisting of 163 amino acid (aa). Genomic southern blot confirmed that soybean genome has two copies of W3 gene. Northern blot analysis was also carried out for the gene expression during heat, NaCl, drought, wounding stresses. The expression of W3 gene specifically induced by heat, NaCl, wounding and drought stress. Using GFP fusion vector, W13-GFP was targeted both to nucleus. For the functional analysis of W3, His-tagged W3 recombinant protein was heterologously expressed in E. coli. The W3 recombinant cells showed enhanced heat tolerance compared to that of vector control cells. We suggest that dnaJ-like W3 protein function as molecular chaperone in the nucleus of the plant cell during various stresses.

1. Ds 삽입변이체 3,000계통으로부터 제초제 저항성 1,874계통을 선발하고 농업적 주요 특성으로서 출수일수, 간장, 수수, 수장, 엽장 등 5가지 형질에 대하여 조사한 바, 조사된 5가지 형질에 대하여 원품종인 동진벼에 비하여 매우 다양한 변이폭을 보여주었다. 2. 농업적 유용성과 관련된 수장이 길고, 조기출수, 수수가 많은 변이체 뿐만 아니라 형태학적 변이를 보이는 twin seedling, dwarf, early heading, strip albino, liguleless 등 변이체가 다수 발견됨으로서 육종적 이용 및 유전자 기능해석을 위한 유용한 집단으로서 유용성을 보여주었다. 3. 서던분석 결과, 벼 게놈상에서 Ds는 평균 2 copy로 전이되었으며 조직부위별로 GUS의 발현을 조사한 결과 잎, 뿌리 및 화기관등에서 약 3.9%가 발현되었다. 이 삽입변이체에서 나타난 다양한 변이형질의 주요 농업적 특성과 GUS 발현의 재현성을 위해 다음 세대의 전개를 통한 후대분석이 필요하다.

We isolated wound-inducible genes using suppression subtractive hybridization (SSH) method and were able to obtain to clone w123 gene encoding dnaJ like protein. The full-length cDNA of w123 is 689 bp with an open reading frame (ORF) consisting of 163 amino acid (aa). Genomic southern blot confirmed that soybean genome has two copies of w123 gene. Northern blot analysis was also carried out for the gene expression during heat, NaCl, drought, wounding stresses. The expression of w123 gene specifically induced by heat, NaCl, wounding and drought stress. Using GFP fusion vector, w123-smGFP was targeted both to nucleus. For the functional analysis of w123, His-tagged w123 recombinant protein was heterologously expressed in E. coli. The w123 recombinant cells showed enhanced heat tolerance compared to that of vector control cells. We suggest that dnaJ-like w123 protein function as molecular chaperone in the nucleus of the plant cell during various stresses.