In animal development, the mechanisms by which localized factors and organelles in egg cytoplasm were exactly distributed into each daughter cell are essential for formation of various cell types. During ascidian Halocynthia roretzi embryogenesis, ooplasmic mitochondria were mainly segregated into muscle and neural precursor cells. At the 32-cell stage, localized mitochondria in the B6.2 blastomeres were preferentially distributed into the B7.4 muscle precursors compared with the B7.3 mesenchyme/ notochord precursors. When the B6.2 blastomeres were isolated from the early 32-cell stage embryos and then allowed to divide 2 times of cell division, the resultant partial embryos showed symmetric distribution of mitochondria, and the partial embryos were composed of equal size cells. In normal development, cell fates of the B7.3 blastomere were correlated with the unequal cleavage of B6.2 lineage cells that normally occurs in the next two-cell division stages to produce a large B8.5 mesenchyme and a small B8.6 notochord cell. Mitochondria are distributed asymmetrically in both cells. When embryos were treated with FGF receptor inhibitor SU5402 and MEK inhibitor U0126 between the 32-cell and the early 64-cell stages, the resultant embryos showed equal cleavage pattern and symmetric distribution of mitochondria in daughter cells of the B6.2 blastomeres. However, blocking of Nodal and Notch signaling did not affect the cell division pattern and mitochondrial distribution in the B6.2 lineage blastomeres between the 32-cell and 110-cell stages. Therefore, it is likely that FGF/MEK signaling is involved in asymmetric distribution of mitochondria and unequal cleavage of the B6.2 lineage blastomeres in ascidian embryo.

Arabidopsis E3 SUMO ligase SIZ1 (AtSIZ1) controls vegetative growth and development including responses to nutrient deficiency and environment stresses. Here, we analyzed the effect of AtSIZ1 on the stability and amount of seed proteins. Proteomic analysis showed that the amount of three major nutrient reservoir proteins, CRUCIFERIN (CRU) 1, 2 and 3, were decreased in siz1-2 mutants. However, quantitative real-time RT-PCR showed that transcript levels of CRU1, 2 and 3 genes were rather significantly higher in siz1-2 mutants than wild-type plants. Yeast two hybrid analysis revealed that AtSIZ1 interacts with CRU1, CRU2 and CRU3, strongly suggesting that CRU1, 2 and 3 proteins are sumoylated by AtSIZ1. In addition, the analysis of amino acid composition by HPLC showed that the contents of amino acids were a bit high in siz1-2 mutants. Our data indicate that AtSIZ1 plays an important function for accumulation of seed storage proteins through its ligase activity.

Sudden enhancements of daytime NmF2 appeared in Anyang ionosonde data during summer seasons in 2006-2007. In order to investigate the causes of this unusual enhancement, we compared Anyang NmF2’s with the total electron contents (GPS TECs) observed at Daejeon, and also with ionosonde data at at mid-latitude stations. First, we found no similar increase in Daejeon GPS TEC when the sudden enhancements of Anyang NmF2 occurred. Second, we investigated NmF2’s observed at other ionosonde stations that use the same ionosonde model and auto-scaling program as the Anyang ionosonde. We found similar enhancements of NmF2 at these ionosonde stations. Moreover, the analysis of ionograms from Athens and Rome showed that there were sporadic-E layers with high electron density during the enhancements in NmF2. The auto-scaling program (ARTIST 4.5) used seems to recognize sporadic-E layer echoes as a F2 layer trace, resulting in the erroneous critical frequency of F2 layer (foF2). Other versions of the ARTIST scaling program also seem to produce similar erroneous results. Therefore we conclude that the sudden enhancements of NmF2 in Anyang data were due to the misrecognition of sporadic-E echoes as a F-layer by the auto-scaling program. We also noticed that although the scaling program flagged confidence level (C-level) of an ionogram as uncertain when a sporadic-E layer occurs, it still automatically computed erroneous foF2’s. Therefore one should check the confidence level before using long term ionosonde data that were produced by an auto-scaling program.

Compared to wide ranges of genetic variation of natural populations, very limited Miscanthus cultivar has been released. This study was the first report on the development of Miscanthus cultivar by means of radiation breeding. Seeds of M. sinensis were initially exposed to gamma rays of 250 Gy for 24 h, generated from a 60Co gamma-irradiator. The irradiated seeds were sown and then the highly tiller-producing mutants were selected for this study. Biomass-related parameters including tiller number, plant height, stem diameter, and leaf number were measured. Ploidy level and internal transcribed spacer (ITS) were investigated to characterize the mutants compared to wild type (WT) Miscanthus. Plant height and tiller number were negatively related, where multi-tillering mutants were relatively short after 4 month growth. However stem diameter and leaf number were greater in mutants. All the materials used in this study were diploid, implying that the mutants with greater tiller numbers and stem diameter were not likely related to polyploidization. Based on the sequence of ITS regions, the mutants demonstrated base changes from the gamma irradiation where G+C content (%) was decreased in the ITS1, but increased in ITS2 when compared to WT sequence. ITS2 region was more variable than in ITS1 in the mutants, which collectively allows identification of the mutants from WT. Those mutants having enhanced tillers and allelic variations might be used as breeding materials for enhanced biomass-producing Miscanthus cultivars.

Boseogchal is a newjaponica rice cultivar developed from the three-way cross ofHwayoung, Tamjin and Sinseonchalat Honam Agricultural Research Institute (HARI), RDA, in 2004. It is a waxy rice with about 117 days of growth duration fromtransplanting to har

Hanmaeum is a new super-yielding japonica rice cultivar developed from a three-way cross of Mi1yang165,YR16365Acp13 and Iksan438 at Honam Agricultural Research Institute (HARI), RDA, in 2004. This cultivar has about 119 daysgrowth duration from transplant

Research Institute (HARI), NTCS, RDA, in 2004. This cultivar has a short grain shape and about 123 days growth duration from trans-planting to harvesting under the reclaimed saline area of the south-western and the mid-western coastal plain and Honam plai

Unkwang is a newjaponica rice cultivar developed from the cross between Sobibyeo (Iksan435), high yield and coldtolerance cultivar and Cheolweon 54, early maturity cultivar at Honam Agricultural Reaserch Institute (HARI), NICS, RDA, m2004. This cultivar h

Self incompatibility (SI) of Cruciferous crop has been studied not only to find out the evolution of the self incompat-ibility system, but also to identify the S haplotypes of the plant materials on the practical breeding programs. It has been reportedtha

“Jokyoung”, a new bread making wheat cultivar, was developed from the cross between “Seri 82”, a hard white wheat from CIMMYT, Mexico and “Keumkang”, a hard white wheat with high milling rate and early maturing from Korea by National Institute of Crop Sci

The six rowed and naked barley cultivar, “Cheongho” (Hordeum vulgare L.), showing earliness, good cooking quality, resistance to powdery mildew and barley yellow mosaic virus disease (BaYMV), winter hardiness, lodging tolerance, and high yield in paddy fi