Soybean (Glycine max (L.) Merr) is a short day plant and has been adapted to various climates and environments during cultivation. However, the cultivation area is restricted to a very narrow range of latitudes. To date, nine major genes (E1 to E8 and J) have been reported to control the flowering time and maturity. Here, we evaluated the role of E2, E3, E4, and their paralogue genes in late flowering soybean cultivars under long day (LD) conditions using Soybean yellow common mosaic virus (SYCMV)-based virus-induced gene silencing (VIGS) system. A total of nine VIGS constructs were infiltrated into two fully expanded cotyledons and primary leaves. After inoculation with these VIGS constructs on Jangyeobkong, which is a late-flowering cultivar, phenotypic traits were evaluated for the first flowering dates (FFDs) and pod maturities under LD conditions. The FFDs of the silenced plants occurred 50-56 days after sowing (das), while the non-silenced plants bloomed on 60-61 days. We found that the E3 paralogue-silenced plants flowered the fastest and responsive genes were identified to be associated with the promotion of flowering time. As the knock-down of E3 paralogue, expression of E1 was up-regulated, E2 was no difference, E3 and E4 genes were down-regulated in the silenced plants. Expression of GmFT2a and GmFT5a is known to be controlled by E3 and E4. Interestingly, GmFT5a were highly expressed in SYCMV:E3 paralogue-silenced plants, whereas the expression of GmFT2a was not significant. These results support that GmFT5a is able to independently promote flowering under LD conditions.

The histological changes in the Ussurian bullhead, Leiocassis ussuriensis, and the Korean bullhead, Pseudobagrus fulvidraco, were observed during the early period of growth. The retinas size of both species increased in the 9 days post-hatching (DPH) (P<0.05). In the just-hatched Ussurian bullhead, the retina already consisted of six layers: the epithelial layer, ganglion cell layer, inner nuclear layer, inner plexiform layer, outer limiting membrane layer, and rod and cone layer. The Korean bullhead had the same components. At 50 DPH, the thickness of the retina was 538.0±7.19 μm in the Ussurian bullhead and 558.9±9.44 μm in the Korean bullhead. The relative thickness of each layer of the retina did not differ significantly in the two species. Although the growth of the Korean bullhead’s retina was faster, the relative thickness of each layer in the retina did not change during early development. After hatching, some parts of the tissue gradually became denser. Immediately after hatching, the kidney and midgut epithelium of the Ussurian bullhead and Korean bullhead were already formed and grew gradually thereafter. From 0 DPH to 30 DPH, the nuclear height in the midgut epithelium did not differ significantly between the two species, but at 50 DPH, it was 11.4±2.45 μm in the Korean bullhead and 9.9±2.13 μm in the Ussurian bullhead. During the experimental period, the major axes, minor axes, surface areas, and volumes of the proximal tubule cells in the kidney did not differ significantly between the two species. Thus, the early histological development of the Ussurian bullhead is similar to that of the Korean bullhead.

Anthocyanins are very important constituent of human diet. In recent years, they have gained much attention due to their antioxidative properties. As the radish (Raphanus sativus L) has rich content of anthocyanins, the study is aimed to develop increased functional radish from selected radish varieties. ‘Bordeux’ is a hybrid variety of breeding between one accession derived from ‘Oharu’ as a maternal variety and ‘Chungpihongsim’ as a paternal variety. In this study, we investigated the new varieties of radish commonly consumed in Republic of Korea for their total phenolic content (TPC) and antioxidant activities using three (DDPH, FRAP and CUPRAC) different assays. The selected radish varieties like ‘Bordeux’, ‘Chungbok’, ‘3209’, ‘Chungwoon’, ‘Oharu’, and ‘Chungpihongsim’ were procured from the company Syngenta Korea. Among the selected radish varieties, ‘Bordeux’ (289 μg/g FW) and ‘Chungpihongsim’ (276 μg/g FW) revealed maximum amount of phenolics; whereas ‘3209’ (103 μg/g FW) and ‘Chungwoon’ (166 μg/g FW) showed the lower amount of phenolics content, respectively. Extracts from these studied radishes showed good to moderate antioxidant activities. The varieties ‘Chungpihongsim’ and ‘Bordeux’ revealed maximum antioxidant activity for all assays as demonstrated. However, some varieties like ‘3209’ and ‘Oharu’ exhibited the lowest antioxidant activity in all the tested assays, viz; DPH, FRAP and CUPRAC in μg TE/g FW, respectively. The antioxidant activities may be attributed to the higher phenolic acid contents as a linear relation was observed between the two components and the antioxidant parameters.

Arabidopsis atDjC53 and atDjC32 gene DnaJ-like protein homologous to DnaJ-like protein was characterized for the functional analysis of DnaJ-like protein. It was shown that atDjC53 and atDjC32 RNA expression is induced by heat shock stress and atDjC53- and atDjC32-GFP was targeted to the nucleus of protoplasts. The atDjC53 and atDjC32 promoter (1 kb) was isolated and fused to the GUS reporter gene to investigate gene regulation of atDjC53 and atDjC32 specific to heat shock stress or to developmental organ in the transgenic lines. RNAi and overexpression construct was employed to generate atDjC53 and atDjC32 knock-out plants for the study of their function. Molecular function of atDjC53 and atDjC32 is discussed in relation to heat shock and also developmental stages in Arabidopsis.

Heat shock transcription factors (HSFs) are the major heat shock factors regulating the heat stress response. They participate in regulating the expression of heat shock proteins (HSPs), which are critical in the protection against stress damage and many other important biological processes. In this study, a genome-wide analysis was carried out to identify all HSFs soybean genes. Twenty six nonredundant HSF genes (GmHsf) were identified in the latest soybean genome sequence. Chromosomal location, protein domain and motif organization of GmHsfs were analyzed in soybean genome. The phylogenetic relationships, gene duplications and expression profiles of GmHsf genes were also presented in this study. According to their structural features, the predicted members were divided into the previously defined classes A–C, as described in Arabidopsis. Using RT-PCR, the expression patterns of 26 GmHsf genes were investigated under heat stress. The data revealed that these genes presented different expression levels in response to heat stress conditions. Real-time (q)RT-PCR was performed to investigate transcript levels of five GmHsfs in response to multiple abiotic stresses. Differential expression of five GmHsfs implies their role during abiotic stresses. Subcellular localization using GFP-fusion protein demonstrated that GmHsf12 and GmHsf34 were restricted to the nucleus and GmHsf28 was localized in the nucleus and cytoplasm in plant. The results provide a fundamental clue for understanding of the complexity of the soybean HSF gene family and cloning specific function genes in further studies and applications.

Salinity stress severely affects plant growth and development causing crop loss worldwide. Suaeda asparagoides is a salt-marsh euhalophyte widely distributed in southwestern foreshore of Korea. To isolate salt tolerance genes from S. asparagoides, we constructed a cDNA library from leaf tissues of S. asparagoides that was treated with 200 mM NaCl. A total of 1,056 clones were randomly selected for EST sequencing, and 932 of them produced readable sequence. By sequence analysis, we identified 538 unigenes and registered each in National Center for Biotechnology Information. The 80 salt stress related genes were selected to study their differential expression. Reverse Transcriptase-PCR and Northern blot analysis revealed that 23 genes were differentially expressed under the high salinity stress conditions in S. asparagoides. They are functionally diverse including transport, signal transduction, transcription factor, metabolism and stress associated protein, and unknown function. Among them dehydrin (SaDhn) and RNA binding protein (SaRBP1) were examined for their abiotic stress tolerance in yeast (Saccharomyces cerevisiae). Yeast overexpressing SaDhn and SaRBP1 showed enhanced tolerance to osmotic, freezing and heat shock stresses. This study provides the evidence that SaRBP1 and SaDhn from S.asparagoides exert abiotic stress tolerance in yeast. Information of salt stress related genes from S. asparagoides will contribute for the accumulating genetic resources to improve osmotic tolerance in plants.

The ubiquitin conjugating enzyme E2 (UBC E2) mediates selective ubiquitination, acting with E1 and E3 enzymes to designate specific proteins for subsequent degradation. In the present study, we characterized the function of the mung bean VrUBC1 gene (Vigna radiata UBC 1). RNA gel-blot analysis showed that VrUBC1 mRNA expression was induced by either dehydration, high salinity or by the exogenous abscisic acid (ABA), but not by low temperature or wounding. Biochemical studies of VrUBC1 recombinant protein and complementation of yeast ubc4/5 by VrUBC1 revealed that VrUBC1 encodes a functional UBC E2. To understand the function of this gene in development and plant responses to osmotic stresses, we overexpressed VrUBC1 in Arabidopsis (Arabidopsis thaliana). The VrUBC1-overexpressing plants displayed highly sensitive responses to ABA and osmotic stress during germination, enhanced ABA- or salt-induced stomatal closing, and increased drought stress tolerance. The expression levels of a number of key ABA signaling genes were increased in VrUBC1-overexpressing plants compared to the wild-type plants. Yeast two-hybrid and bimolecular fluorescence complementation demonstrated that VrUBC1 interacts with AtVBP1 (A. thaliana VrUBC1 Binding Partner 1), a C3HC4-type RING E3 ligase. Overall, these results demonstrate that VrUBC1 plays a positive role in osmotic stress tolerance through transcriptional regulation of ABA-related genes and possibly through interaction with a novel RING E3 ligase.