Rapid diagnosis of two marine viruses, red sea bream iridovirus and viral hemorrhagic septicemia virus by PCR combined with lateral flow assay.

Red sea bream iridovirus (RSIV) and Viral hemorrhagic septicemia virus (VHSV) are the most important viral marine pathogens in South Korea because RSIV and VHSV infect and cause high mortality rates in major fish species such as Paralichthys olivaceus and Sebastes schlegelii. These viruses can be transmitted both vertically and horizontally, and early diagnosis is imperative. In this research, RSIV and VHSV viral genomes are detected by PCR-lateral flow assay (LFA). PCR-LFA is sensitive, capable of detecting a viral genome at a concentration of 2-200 fg/µL. Development of this detection method is very meaningful because LFA is simple, requiring a minimum of personnel training to perform. Additionally, LFA requires less time than other detection methods and can be an immediate detection tool that is indispensable in preventing rapid viral spread.

Glutathione alleviated peripheral neuropathy in oxaliplatin-treated mice by removing aluminum from dorsal root ganglia.

Oxaliplatin, a platinum-based anti-cancer drug, induces peripheral neuropathy as a side effect and causes cold hyperalgesia in cancer patients receiving anti-cancer chemotherapy. In oxaliplatin-treated mice, aluminum was accumulated in the dorsal root ganglia (DRG), and accumulated aluminum in DRG or other organs aggravated oxaliplatin-induced neuropathic pain. To investigate whether aluminum oxalate, which is the compound of aluminum and oxaliplatin, might be the peripheral neuropathy inducer, the withdrawal responses of mice to coldness, the expression of transient receptor potential ankyrin 1 and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays in DRG were analyzed in mice administered with aluminum oxalate. In addition, the concentrations of aluminum in aluminum oxalate-treated mice were significantly increased compared to those of mice treated with aluminum chloride. To alleviate neuropathic pain, glutathione (GSH), known as an antioxidant and a metal chelator, was injected into oxaliplatin-treated mice. The concentrations of aluminum in the DRG were decreased by the chelation action of GSH. Taken together, behavioral and molecular analyses also supported that aluminum accumulation on the DRG might be a factor for neuropathic pain. This result also suggested that the aluminum chelation by GSH can provide an alleviatory remedy of neuropathic pain for cancer patients with oxaliplatin-induced neuropathic pain.

Human skeletal dysplasia caused by a constitutive activated transient receptor potential vanilloid 4 (TRPV4) cation channel mutation.

The transient receptor potential vanilloid 4 (TRPV4) cation channel, a member of the TRP vanilloid subfamily, is expressed in a broad range of tissues where it participates in the generation of Ca²âº signals and/or depolarization of the membrane potential. Regulation of TRPV4 abundance at the cell surface is critical for osmo- and mechanotransduction. Defects in TRPV4 are the cause of several human diseases, including brachyolmia type 3 (MIM:113500) (also known as brachyrachia or spondylometaphyseal dysplasia Kozlowski type [MIM:118452]), and metatropic dysplasia (MIM:156530) (also called metatropic dwarfism or parastremmatic dwarfism [MIM:168400]). These bone dysplasia mutants are characterized by severe dwarfism, kyphoscoliosis, distortion and bowing of the extremities, and contractures of the large joints. These diseases are characterized by a combination of decreased bone density, bowing of the long bones, platyspondyly, and striking irregularities of endochondral ossification with areas of calcific stippling and streaking in radiolucent epiphyses, metaphyses, and apophyses. In this review, we discuss the potential effect of the mutation on the regulation of TRPV4 functions, which are related to human diseases through deviated function. In particular, we emphasize how the constitutive active TRPV4 mutant affects endochondral ossification with a reduced number of hypertrophic chondrocytes and the presence of cartilage islands within the zone of primary mineralization. In addition, we summarize current knowledge about the role of TRPV4 in the pathogenesis of several diseases.

Phylogenetic lineage of Tobacco leaf curl virus in Korea and estimation of recombination events implicated in their sequence variation.

New strains of Tobacco leaf curl virus (TbLCV) were isolated from tomato plants in four different local communities of Korea, and hence were designated TbLCV-Kr. Phylogenetic analysis of the sequences of the whole genome and of individual ORFs of these viruses indicated that they are closely related to the Tobacco leaf curl Japan virus (TbLCJV) cluster, which includes Honeysuckle yellow vein virus (HYVV), Honeysuckle yellow vein mosaic virus (HYVMV), and TbLCJV isolates. Four putative recombination events were recognized within these virus sequences, suggesting that the sequence variations observed in these viruses may be attributable to intraspecific and interspecific recombination events involving some TbLCV-Kr isolates, Papaya leaf curl virus (PaLCV), and a local isolate of Tomato yellow leaf curl virus (TYLCV).

Agroinoculation of Nicotiana benthamiana with cloned honeysuckle yellow vein virus isolated from Lonicera japonica.

A new honeysuckle yellow vein geminivirus (HYVV) isolate (2,763 nucleotides) and the HYVV-ß satellite (1,227 nucleotides) from Korea were cloned and characterized from symptomatic leaves of Lonicera japonica with a yellow net mosaic appearance. Phylogenetic analysis of HYVV and 13 other begomoviruses revealed that HYVV has the highest nucleotide sequence homology to HYVV-UK2. Grafting challenge of a virus-free L. japonica (scion) on an HYVV-infected L. japonica (stock) resulted in the appearance of typical HYVV disease symptoms on the newly developed leaves of the scion. Two pMon521 plasmids containing 1.3 copies and 2.0 copies of the cloned HYVV isolate, respectively, were infectious and produced disease symptoms in Nicotiana benthamiana after agroinoculation. We conclude that the causal agent of yellow net mosaic in L. japonica is a new Korean isolate of HYVV, based on sequence comparisons, agroinoculation-induced disease symptoms, electron microscopy, and phylogenetic analysis.

Phylogenetic analysis and inflow route of Tomato yellow leaf curl virus (TYLCV) and Bemisia tabaci in Korea.

Tomato yellow leaf curl virus (TYLCV) is a member of the genus Begomovirus of the family Geminiviridae, members of which are characterized by closed circular single-stranded DNA genomes of 2.7-2.8 kb in length, and include viruses transmitted by the Bemisia tabaci whitefly. No reports of TYLCV in Korea are available prior to 2008, after which TYLCV spread rapidly to most regions of the southern Korean peninsula (Gyeongsang-Do, Jeolla-Do and Jeju-Do). Fifty full sequences of TYLCV were analyzed in this study, and the AC1, AV1, IR, and full sequences were analyzed via the muscle program and bayesian analysis. Phylogenetic analysis demonstrated that the Korea TYLCVs were divided into two subgroups. The TYLCV Korea 1 group (Masan) originated from TYLCV Japan (Miyazaki) and the TYLCV Korea 2 group (Jeju/Jeonju) from TYLCV Japan (Tosa/Haruno). A B. tabaci phylogenetic tree was constructed with 16S rRNA and mitochondria cytochrome oxidase I (MtCOI) sequences using the muscle program and MEGA 4.0 in the neighbor-joining algorithm. The sequence data of 16S rRNA revealed that Korea B. tabaci was closely aligned to B. tabaci isolated in Iran and Nigeria. The Q type of B. tabaci, which was originally identified as a viruliferous insect in 2008, was initially isolated in Korea as a non-viruliferous insect in 2005. Therefore, we suggest that two TYLCV Japan isolates were introduced to Korea via different routes, and then transmitted by native B. tabaci.

Expression analysis of proline metabolism-related genes from halophyte Arabis stelleri under osmotic stress conditions.

Arabis stelleri var. japonica evidenced stronger osmotic stress tolerance than Arabidopsis thaliana. Using an A. thaliana microarray chip, we determined changes in the expression of approximately 2 800 genes between A. stelleri plants treated with 0.2 M mannitol versus mock-treated plants. The most significant changes in the gene expression patterns were in genes defining cellular components or in genes associated with the endomembrane system, stimulus response, stress response, chemical stimulus response, and defense response. The expression patterns of three de novo proline biosynthesis enzymes were evaluated in A. stelleri var. japonica seedlings treated with 0.2 M mannitol, 0.2 M sorbitol, and 0.2 M NaCl. The expression of Δ¹ -pyrroline-5-carboxylate synthetase was not affected by NaCl stress but was similarly induced by mannitol and sorbitol. The proline dehydrogenase gene, which is known to be repressed by dehydration stress and induced by free L-proline, was induced at an early stage by mannitol treatment, but the level of proline dehydrogenase was increased later by treatment with both mannitol and NaCl. The level of free L-proline accumulation increased progressively in response to treatments with mannitol, sorbitol, and NaCl. Mannitol induced L-proline accumulation more rapidly than NaCl or sorbitol. These findings demonstrate that the osmotic tolerance of the novel halophyte, Arabis stelleri, is associated with the accumulation of L-proline.

Production of recombinant single chain antibodies (scFv) in vegetatively reproductive Kalanchoe pinnata by in planta transformation.

We developed an asexual reproductive plant, Kalanchoe pinnata, as a new bioreactor for plant-based molecular farming using a newly developed transformation method. Leaf crenate margins were pin-pricked to infect the plant with the Agrobacterium strain LBA4404 and vacuum infiltration was also applied to introduce the target gene into the plants. Subsequently, the young mother leaf produced new clones at the leaf crenate margins without the need for time- and labor-consuming tissue culture procedures. The average transformation rates were approximately 77 and 84% for pin-prickling and vacuum-infiltration methods, respectively. To functionally characterize an introduced target protein, a nucleic acid hydrolyzing recombinant 3D8 scFv was selected and the plant based 3D8 scFv proteins were purified and analyzed. Based on abzyme analysis, the purified protein expressed with this system had catalytic activity and exhibited all of properties of the protein produced in an E. coli system. This result suggested that vegetatively reproductive K. pinnata can be a novel and potent bioreactor for bio-pharmaceutical proteins.

Regulation Fe65 localization to the nucleus by SGK1 phosphorylation of its Ser566 residue.

Fe65 is characterized as an adaptor precursor (APP) through its PID2 element, as well as with the other members of the APP protein family. With the serum- and glucocorticoid-induced kinase 1 (SGK1) substrate specificity information, we found that the putative site of phosphorylation in Fe65 by SGK1 is present on its Ser(566) residue in (560)CRVRFLSFLA(569)(X60469). Thus, we demonstrated that Fe65 and the fluorescein-labeled Fe65 peptide FITC-(560)CRVRFLSFLA(569) are phosphorylated in vitro by SGK1. Phosphorylation of the Ser(566) residue was also demonstrated using a Ser566 phospho-specific antibody. The phospho Fe65 was found mainly in the nucleus, while Fe65 S556A mutant was localized primarily to the cytoplasm. Therefore, these data suggest that SGK1 phosphorylates the Ser(566) residue of Fe65 and that this phosphorylation promotes the migration of Fe65 to the nucleus of the cell.

Transcription factor CP2 is involved in activating mBMP4 in mouse mesenchymal stem cells.

CP2 is a member of a family of transcription factors that regulate genes involved in events from early development to terminal differentiation. In an effort to understand how it selects its target genes we carried out a database search, and located several CP2 binding motifs in the promoter region of bone morphogenetic protein-4 (BMP4). BMP4 is a key regulator of cell fate and body patterning throughout development. For the CP2 binding motifs in BMP4 promoter region to be relevant in vivo, CP2 and BMP4 should be expressed together. We found that CP2b and CP2c, two potent transcriptional activators, are expressed in a manner similar to BMP4 during osteoblast differentiation of C3H10T1/2 cells. In in vitro assays, the CP2 proteins bound to two CP2 binding motifs (-715 to -676 and -147 to -118) in the BMP4 promoter, and luciferase reporter assays indicated that this binding was essential for transcription of BMP4 during osteoblast differentiation. Taken together, our data indicate that CP2b and CP2c play important roles during bone development by activating BMP4 transcription.

Altered cell shapes, hyperplasia, and secondary growth in Arabidopsis caused by beet curly top geminivirus infection.

Arabidopsis Sei-O ecotype was found to be hypersusceptible to the BCTV-Logan strain in that it developed very severe symptoms, including severely deformed inflorescences with the callus-like structure, and accumulated high level of viral DNA. Microscopic studies of the BCTV-induced cell divisions demonstrated that the activation of cell divisions was preceded by the phloem disruption and the callus-like structure seemed to be originated from the cortex nearby disrupted phloem. We have further defined the callus-like structure formed by BCTV infection using molecular and histochemical analyses. Results indicate that BCTV infection causes the phloem disruption, following by cell enlargement and elongation in cortex and even epidermis. Finally, BCTV induced symptomatic secondary growth in cortex by de novo anticlinal and periclinal cell divisions. Expression of cdc2 and saur from BCTV-infected Arabidopsis correlates with symptom development. These results suggest a critical role of auxin in symptom development in the interactions between Arabidopsis and BCTV.

Transgenic down-regulation of caffeic acid O-methyltransferase (COMT) led to improved digestibility in tall fescue (Festuca arundinacea).

Dry matter digestibility is one of the most important characteristics of forage. The major constraint on ruminant digestion of forage cell walls is lignin. Sequences of cDNA encoding a key lignin biosynthetic enzyme, caffeic acid O-methyltransferase (COMT), was cloned from the widely grown monocot forage species tall fescue (Festuca arundinacea Schreb.). Enzymatic properties of recombinant COMT protein expressed in E. coli were determined using six substrates. The preferred substrates for tall fescue recombinant COMT were 5-hydroxyferulic acid and caffeoyl aldehyde. Transgenic tall fescue plants carrying either sense or antisense COMT gene constructs were obtained by microprojectile bombardment of single-genotype-derived embryogenic suspension cells. Consistent and closely related molecular and biochemical data demonstrated that two co-suppressed transgenic lines were down-regulated in their lignin biosynthesis. These COMT down-regulated transgenic tall fescue plants showed substantially reduced levels of transcripts, significantly reduced enzymatic activities, significantly decreased lignin content, apparently altered lignin composition and significantly increased (9.8-10.8%) digestibility.

The surface receptor is involved in annexin I-stimulated insulin secretion in MIN6N8a cells.

This study investigated the effect of extracellular annexin I on regulating insulin secretion in MIN6N8a (an insulin secreting cell line) cells. The properties of annexin I receptor in MIN6N8a cells were also determined. Annexin I stimulated insulin release in MIN6N8a cells, regardless of the presence or absence of extracellular Ca(2+). Confocal microscopy revealed that annexin I bound to the surface of MIN6N8a cells. In addition, FACs analysis showed that annexin I bound to the surface of MIN6N8a cells in a dose-dependent manner. However, the annexin I-stimulated insulin secretion and the annexin I binding were abolished in MIN6N8a cells treated with proteases. Annexin I receptors were regenerated time-dependently. Furthermore, annexin I-stimulated insulin secretion was inhibited by cycloheximide but not by actinomycin D. These results showed that annexin I binds to the surface receptor in order to regulate the stimulation of insulin release in MIN6N8a cells.

New preparation of PM2 phage DNA and an endonuclease assay for a single-strand break.

PM2 is a bacteriophage which has closed circular double-stranded DNA as a genome, which is the sole source for endonuclease assay for a single strand break in the fmol range. Therefore, it is important to isolate PM2 DNA with low control nicks for the endonuclease assay. Usually, the isolation method of phage DNA is to use ultracentrifugation which takes at least 4 days. In this report, a fast and effective method which takes only 2 days was developed to purify DNA using polyethylene glycol (PEG) 8000 and the yields of phage DNA isolated by these two methods were compared. The method using PEG 8000 increased the yield of PM2 DNA from 31.2% to 45.2%, and decreased the nick from 17.1% to 13.1%. Recently, the complete PM2 DNA genome sequence of 10,079 bp was published. The exact number of nucleotides of PM2 DNA is important for the correct enzyme assay which measures nicks generated by an endonuclease. The correct calculation of endonuclease activity of rpS3 for nick-circle assay was performed to measure single-strand breaks in this report.

Improved forage digestibility of tall fescue (Festuca arundinacea) by transgenic down-regulation of cinnamyl alcohol dehydrogenase.

Lignification of cell walls during plant development has been identified as the major factor limiting forage digestibility and concomitantly animal productivity. cDNA sequences encoding a key lignin biosynthetic enzyme, cinnamyl alcohol dehydrogenase (CAD), were cloned from the widely grown monocotyledonous forage species tall fescue (Festuca arundinacea Schreb.). Recombinant tall fescue CAD expressed in E. coli exhibited the highest V(max)/K(m) values when coniferaldehyde and sinapaldehyde were used as substrates. Transgenic tall fescue plants carrying either sense or antisense CAD gene constructs were obtained by microprojectile bombardment of single genotype-derived embryogenic suspension cells. Severely reduced levels of mRNA transcripts and significantly reduced CAD enzymatic activities were found in two transgenic plants carrying sense and antisense CAD transgenes, respectively. These CAD down-regulated transgenic lines had significantly decreased lignin content and altered ratios of syringyl (S) to guaiacyl (G), G to p-hydroxyphenyl (H) and S to H units. No significant changes in cellulose, hemicellulose, neutral sugar composition, p-coumaric acid and ferulic acid levels were observed in the transgenic plants. Increases of in vitro dry matter digestibility of 7.2-9.5% were achieved in the CAD down-regulated lines, thus providing a novel germplasm to be used for the development of grass cultivars with improved forage quality.

Purification and characterization of a cytosolic phospholipase A2 from rat liver.

A cytosolic phospholipase A2 (PLA2) was purified 640-fold from rat liver by sequential anion-exchange chromatography, Ca2+-precipitation/KCl-solubilization, gel filtration chromatography, and affinity chromatography. A single peak of PLA2 activity was eluted at an apparent molecular mass of 197 kDa from a Superdex 200HR gel filtration column. In the presence of Ca2+, the purified enzyme catalyzed the hydrolysis of 81.8 nmol of phosphatidylethanolamine per hour per mg of protein. The apparent Km was 1.83 nM. The enzyme was inhibited by arachidonyl trifluoromethyl ketone (AACOCF3), an inhibitor of cPLA2. However, it was not inhibited by bromoenol lactone (BEL), an inhibitor of iPLA2, and p-bromophenacyl bromide (p-BPB), an inhibitor of sPLA2. These data suggest that the purified enzyme is a novel Ca2+-dependent cytosolic PLA2.

Effect of annexin I on insulin secretion through surface binding sites in rat pancreatic islets.

This study investigates the effect of extracellular annexin I (Anx I) on regulating insulin secretion in isolated rat pancreatic islets. Results show that Anx I stimulates insulin release in pancreatic islets regardless of the presence or absence of extracellular Ca2+. In particular, confocal microscopy shows that Anx I binds to the surface of islet cells in the absence of extracellular Ca2+. However, insulin secretion through Anx I significantly decreases in trypsin-treated islets. Likewise, there is minimal binding of Anx I to the surface of trypsin-treated islets. Anti-Anx I polyclonal antibody also inhibits the stimulating effect of Anx I on insulin secretion. These results indicate that Anx I is capable of binding to the cell surface receptor, in order to regulate the stimulation of insulin release in rat pancreatic islets.

Comparative binding of antitumor drugs to DNA containing the telomere repeat sequence.

Telomeres are the ends of the linear chromosomes of eukaryotes and consist of tandem GT-rich repeats in telomere sequence i.e. 500-3000 repeats of 5'-TTAGGG-3' in human somatic cells, which are shortened gradually with age. The G-rich overhang of telomere sequence can adopt different intramolecular fold-backs and tetra-stranded DNA structures, in vitro, which inhibit telomerase activity. In this report, DNA binding agents to telomere sequence were studied novel therapeutic possibility to destabilize telomeric DNA sequences. Oligonucleotides containing the guanine repeats in human telomere sequence were synthesized and used for screening potential antitumor drugs. Telomeric DNA sequence was characterized using spectral measurements and CD spectroscopy. CD spectrum indicated that the double-stranded telomeric DNA is in a right-handed conformation. Polyacrylamide gel electrophoresis was performed for binding behaviors of antitumor compounds with telomeric DNA sequence. Drugs interacted with DNA sequence caused changes in the electrophoretic mobility and band intensity of the gels. Depending on the binding mode of the anticancer drugs, telomeric DNA sequence was differently recognized and the efficiency of cleavage of DNA varies in the bleomycin-treated samples under different conditions. DNA cleavage occurred at about 1% by the increments of 1 micromM bleomycin-Fe(III). These results imply that the stability of human telomere sequence is important in conjunction with the cancer treatment and aging process.