Lignin-based barrier restricts pathogens to the infection site and confers resistance in plants.

Pathogenic bacteria invade plant tissues and proliferate in the extracellular space. Plants have evolved the immune system to recognize and limit the growth of pathogens. Despite substantial progress in the study of plant immunity, the mechanism by which plants limit pathogen growth remains unclear. Here, we show that lignin accumulates in Arabidopsis leaves in response to incompatible interactions with bacterial pathogens in a manner dependent on Casparian strip membrane domain protein (CASP)-like proteins (CASPLs). CASPs are known to be the organizers of the lignin-based Casparian strip, which functions as a diffusion barrier in roots. The spread of invading avirulent pathogens is prevented by spatial restriction, which is disturbed by defects in lignin deposition. Moreover, the motility of pathogenic bacteria is negatively affected by lignin accumulation. These results suggest that the lignin-deposited structure functions as a physical barrier similar to the Casparian strip, trapping pathogens and thereby terminating their growth.

Allergenic characterization of Bomb m 4, a 30-kDa Bombyx mori lipoprotein 6 from silkworm pupa.

BACKGROUND: Silkworm pupa (SWP) food anaphylaxis has been described frequently in Asian countries. However, false-positive reactions by skin pricks and serum IgE (sIgE) tests to the extract complicate diagnosis, requiring identification of clinically relevant major allergens. OBJECTIVES: In this study, we characterized a novel SWP allergen, Bomb m 4, a 30-kDa lipoprotein, and evaluated its diagnostic sensitivity. METHODS: Bomb m 4 was identified by a proteomic analysis. This recombinant (r)Bomb m 4 was overexpressed in Escherichia coli, and the IgE reactivity by ELISA was compared with other reported allergenic proteins: Bomb m 1 (arginine kinase), 27-kDa glycoprotein, Bomb m 3 (tropomyosin) using the serum samples from 17 SWP allergic patients and 11 asymptomatic sensitized subjects. RESULTS: rBomb m 4-specific IgE was recognized by all 17 SWP allergic patients. The 27-kDa glycoprotein and Bomb m 1 sIgE were found in 35.3% and 0%, respectively, in the SWP allergic patients. ELISA sIgE reactivity increased significantly, when 4 M urea was added in serum samples. However, only 16% inhibition of sIgE reactivity to the whole SWP extract was exhibited by rBomb m 4, whereas more than 93% of self-inhibition of rBomb m 4 sIgE was obtained, possibly due to the low abundance of Bomb m 4 in the extract. Three linear epitopes (81-95, 191-205 and 224-238 residues) of rBomb m 4 were identified. These epitopes are shown to be released by pepsin digestion. Receiver operator characteristic (ROC) analysis showed the highest diagnostic value of Bomb m 4 followed by Bomb m 1, 27-kDa glycoprotein and Bomb m 3. CONCLUSION: Bomb m 4 is the major allergen of SWP allergic patients. It has cryptic epitopes which are exposed to IgE antibodies with digestive enzymes. This recombinant Bomb m 4 allergen permits exact diagnosis of SWP allergy.

Recurrence of clinical events at the same anatomical location in patients with MOG antibody-associated disease.

OBJECTIVES: Likelihood of clinical events occurring within the same anatomical location in patients with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) was retrospectively investigated. METHODS: A total of 236 clinical events in 90 patients with MOGAD from nine referral hospitals were analyzed via logistic regression, and odds ratios (ORs) were calculated. Anatomical lesion location was divided into four groups; optic nerve, spinal cord, cerebral hemisphere, and brainstem/cerebellum. RESULTS: At all locations, there was an increased likelihood of a second attack occurring at the same location as the initial event (cerebral hemisphere OR = 22.14, brainstem/cerebellum OR = 18.4, spinal cord OR = 9.1, and optic nerve OR = 7.8). There was an increased likelihood of a third attack occurring at the same location as the initial event in the optic nerve (OR = 14.9), cerebral hemisphere (OR = 11.7), and spinal cord (OR = 6.7). There were positive trends toward a third clinical event occurring at the same location as the first and/or second events if the event was in the optic nerve (OR = 13.5), cerebral hemisphere (OR = 6.9), or spinal cord (OR = 5.7). CONCLUSIONS: The current study suggests that clinical relapses of MOGAD during early stage tend to recur at the same anatomical locations in the central nervous system.

Comparison of MOG and AQP4 antibody seroprevalence in Korean adults with inflammatory demyelinating CNS diseases.

We aimed to compare seroprevalence of anti-myelin oligodendrocyte glycoprotein (MOG) and anti-aquaporin-4 (AQP4) antibodies in Korean adults with inflammatory demyelinating diseases (IDDs) of the central nervous system (CNS), based on a multicenter nationwide database. Sera were analyzed using a live cell-based assay for MOG and AQP4 antibodies. Of 586 Korean adults with IDDs of the CNS, 36 (6.1%) and 185 (31.6%) tested positive for MOG and AQP4 antibodies, respectively. No participant showed double positivity. Seroprevalence of MOG antibodies was about five times lower than that of AQP4 antibodies in a large cohort of Korean adults with IDDs of the CNS.

Controlling Graphene Wrinkles through the Phase Transition of a Polymer with a Low Critical Solution Temperature.

A novel method for controlling reduced graphene oxide (rGO) wrinkles through a phase transition in a solution using a low critical solution temperature (LCST) polymer dispersant has been developed. The polymer dispersant is designed by control of architecture and composition using reversible addition-fragmentation chain transfer polymerization. Synthesized poly(2-(dimethylaminoethyl) methacrylate-block-styrene) (PDbS) can be successfully functionalized on the rGO surface via noncovalent functionalization. PDbS-functionalized rGO (PDbS-rGO) exhibits good dispersibility in an aqueous phase at room temperature and forms wrinkles on the PDbS-rGO surface because of phase transition at the LCST of the polymer dispersant. The formation of PDbS-rGO wrinkles is controlled by varying the aggregation number of the polymer dispersant on the PDbS-rGO surface that strongly depends on temperature. This is confirmed by transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy (ID' /IG ratios are 0.560, 0.579, and 0.684, which correspond to 45, 70, and 95 °C, respectively). In addition, the mechanism of wrinkle control is proved by gold nanoparticles that are grown in polymer dispersant on the PDbS-rGO surface.

Cyclic Peptide Mimotopes for the Detection of Serum Anti-ATIC Autoantibody Biomarker in Hepato-Cellular Carcinoma.

Tumor-associated (TA) autoantibodies have been identified at the early tumor stage before developing clinical symptoms, which holds hope for early cancer diagnosis. We identified a TA autoantibody from HBx-transgenic (HBx-tg) hepatocellular carcinoma (HCC) model mouse, characterized its target antigen, and examined its relationship to human HCC. The mimotopes corresponding to the antigenic epitope of TA autoantibody were screened from a random cyclic peptide library and used for the detection of serum TA autoantibody. The target antigen of the TA autoantibody was identified as an oncogenic bi-functional purine biosynthesis protein, ATIC. It was upregulated in liver cancer tissues of HBx-tg mouse as well as human HCC tissues. Over-expressed ATIC was also secreted extracellularly via the cancer-derived exosomes, which might cause auto-immune responses. The cyclic peptide mimotope with a high affinity to anti-ATIC autoantibody, CLPSWFHRC, distinguishes between serum samples from HCC patients and healthy subjects with 70.83% sensitivity, 90.68% specificity (AUC = 0.87). However, the recombinant human ATIC protein showed a low affinity to anti-ATIC autoantibody, which may be incompatible as a capture antigen for serum TA autoantibody. This study indicates that anti-ATIC autoantibody can be a potential HCC-associated serum biomarker and suggests that autoantibody biomarker's efficiency can be improved by using antigenic mimicry to native antigens present in vivo.

Efficacy and safety of combination antifungal therapy in Korean haematological patients with invasive aspergillosis.

This randomised, double-blind, placebo-controlled trial assessed the efficacy, safety and tolerability of voriconazole+anidulafungin (combination) or voriconazole+placebo (monotherapy) for invasive aspergillosis (IA; NCT00531479). We present a post hoc analysis of Korean and non-Korean patients with IA (including baseline positive serum galactomannan [GM]). Immunocompromised patients ≥ 16 years with IA were randomised 1:1, combination or monotherapy, for ≥ 2 weeks' treatment. The primary endpoint was 6- and 12-week all-cause mortality (Korean modified intent-to-treat [mITT] population). Overall, 454 patients enrolled (Koreans: 56 [combination: 28, monotherapy: 28], non-Koreans: 398 [combination: 200, monotherapy: 198]). The mITT population comprised 40 Koreans (combination: 23; monotherapy: 17) and 237 non-Koreans (combination: 112; monotherapy: 125). Week 6 treatment difference in mortality rate between combination and monotherapy was -6.4% in non-Koreans. This reduction was more marked in Koreans (-22.4%). Week 12 difference in all-cause mortality between combination and monotherapy was -17.7% (Koreans) and -20.2% at Week 6 (Koreans; positive baseline GM). Week 6 mortality (Koreans [mITT]; baseline GM >0.5-2.0) was 0/13 (combination) and 2/6 (monotherapy). Serious adverse events were numerically higher for combination than monotherapy (Koreans: 57.1%, 46.4%; non-Koreans: 49.5%, 46.0%). In Koreans, combination therapy was associated with marginally better outcomes than monotherapy and more so than in non-Koreans.

Identification of anti-SF3B1 autoantibody as a diagnostic marker in patients with hepatocellular carcinoma.

BACKGROUND: Tumor-associated (TA) autoantibodies, which are generated by the immune system upon the recognition of abnormal TA antigens, are promising biomarkers for the early detection of tumors. In order to detect autoantibody biomarkers effectively, antibody-specific epitopes in the diagnostic test should maintain the specific conformations that are as close as possible to those presenting in the body. However, when using patients' serum as a source of TA autoantibodies the characterization of the autoantibody-specific epitope is not easy due to the limited amount of patient-derived serum. METHODS: To overcome these limits, we constructed a B cell hybridoma pool derived from a hepatocellular carcinoma (HCC) model HBx-transgenic mouse and characterized autoantibodies derived from them as tumor biomarkers. Their target antigens were identified by mass spectrometry and the correlations with HCC were examined. With the assumption that TA autoantibodies generated in the tumor mouse model are induced in human cancer patients, the enzyme-linked immunosorbent assays (ELISA) based on the characteristics of mouse TA autoantibodies were developed for the detection of autoantibody biomarkers in human serum. To mimic natural antigenic structures, the specific epitopes against autoantibodies were screened from the phage display cyclic random heptapeptide library, and the streptavidin antigens fused with the specific epitopes were used as coating antigens. RESULTS: In this study, one of HCC-associated autoantibodies derived from HBx-transgenic mouse, XC24, was characterized. Its target antigen was identified as splicing factor 3b subunit 1 (SF3B1) and the high expression of SF3B1 was confirmed in HCC tissues. The specific peptide epitopes against XC24 were selected and, among them, XC24p11 cyclic peptide (-CDATPPRLC-) was used as an epitope of anti-SF3B1 autoantibody ELISA. With this epitope, we could effectively distinguish between serum samples from HCC patients (n = 102) and healthy subjects (n = 85) with 73.53% sensitivity and 91.76% specificity (AUC = 0.8731). Moreover, the simultaneous detection of anti-XC24p11 epitope autoantibody and AFP enhanced the efficiency of HCC diagnosis with 87.25% sensitivity and 90.59% specificity (AUC = 0.9081). CONCLUSIONS: ELISA using XC24p11 peptide epitope that reacts against anti-SF3B1 autoantibody can be used as a novel test to enhance the diagnostic efficiency of HCC.

Epidemiology and Risk Factors for Invasive Fungal Diseases among Allogeneic Hematopoietic Stem Cell Transplant Recipients in Korea: Results of "RISK" Study.

Incidence, epidemiology, and risk factors of invasive fungal diseases (IFDs) in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients can vary from different cohorts and countries. Therefore, we performed a nationwide study to establish a proper antifungal prophylaxis strategies based on risk stratifications of IFDs after all-HSCT in Korea (RISK study). This was a multicenter, retrospective, and observational study in Korea. All consecutive adult patients who received allo-HSCT in 2013 were included. The 12-month cumulative incidence of proven/probable IFDs (PP-IFDs) was calculated during the early (days 0 to 40), late (days 41 to 100), and very late (days 101 to 365) phases after allo-HSCT. Cox proportional hazard regression analysis was performed to identify risk factors for PP-IFDs at each phase. A total 521 allo-HSCT cases in 518 patients were analyzed. Overall cumulative incidence of PP-IFDs were 4.09% (95% confidence interval [CI], 2.38 to 5.81), 7.38% (95% CI, 5.09 to 9.67), and 15.36% (95% CI, 12.04 to 18.68) at the early, late and very phases, respectively. In multiple Cox regression analysis, variables were associated with PP-IFDs in each period were identified. Variables associated with early phase include underlying pulmonary diseases, underlying nonmalignant stable or chronic disease at allo-HSCT, unrelated or family mismatched donor, and prolonged neutropenia. Variables associated with the late phase include high ferritin level at the time point of allo-HSCT, use of secondary immunosuppressive agents due to refractory graft-versus-host disease (GVHD), and cytomegalovirus reactivation. For the very late phase, variables were secondary neutropenia, severe chronic GVHD, and use of TNF-alpha inhibitor for refractory GVHD. This study revealed the high cumulative incidence of IFDs in Korean allo-HSCT recipients, which have distinct risk factors in each phase after allo-HSCT. Our findings indicate that tailored antifungal prophylaxis is necessary for high-risk patients. Clinicians should consider using mold-active antifungal prophylaxis in allo-HSCT recipients who have high risks at different treatment period.

Cellular Localization of Wheat High Molecular Weight Glutenin Subunits in Transgenic Rice Grain.

Rice (Oryza sativa L.) is a primary global food cereal. However, when compared to wheat, rice has poor food processing qualities. Dough that is made from rice flour has low viscoelasticity because rice seed lacks storage proteins that are comparable to gluten protein from wheat. Thus, current research efforts aim to improve rice flour processing qualities through the transgenic expression of viscoelastic proteins in rice seeds. In this study, we characterized the transgenic expression of wheat glutenin subunits in rice seeds. The two genes 1Dx5_KK and 1Dy10_JK, which both encode wheat high-molecular-weight glutenin subunits that confer high dough elasticity, were cloned from Korean wheat cultivars KeumKang and JoKyung, respectively. These genes were inserted into binary vectors under the control of the rice endosperm-specific Glu-B1 promoter and were expressed in the high-amylose Korean rice cultivar Koami (Oryza sativa L.). Individual expression of both glutenin subunits was confirmed by SDS-PAGE and immunoblot analyses performed using T3 generation of transgenic rice seeds. The subcellular localization of 1Dx5_KK and 1Dy10_JK in the rice seed endosperm was confirmed by immunofluorescence analysis, indicating that the wheat glutenin subunits accumulate in protein body-II and novel protein body types in the rice seed. These results contribute to our understanding of engineered seed storage proteins in rice.

2-Hydroxymelatonin promotes the resistance of rice plant to multiple simultaneous abiotic stresses (combined cold and drought).

We investigated the physiological roles of 2-hydroxymelatonin (2-OHMel) in rice seedlings. When they were challenged with simultaneous multiple abiotic stressors, such as a combination of cold and drought, those pretreated with 2-OHMel were resistant, whereas no tolerance was observed in seedlings treated with either melatonin or water (control). The tolerance phenotype was associated with the induction of several transporter proteins, including the proton transporter (UCP1), potassium transporter (HKT1), and water channel protein (PIP2;1). Treatment with 2-OHMel increased the content of the osmoprotectant proline and maintained mitochondrial structure when plants were subjected to a combination of cold and drought stress. We screened the corresponding transcription factors (TFs) for 2-OHMel-mediated resistance to the combined stressors through analysis of large numbers of cold- and drought-related TFs. Two TFs, Myb4 and AP37, were only induced by 2-OHMel treatment. Transgenic rice lines overexpressing rice Myb4 were not resistant to the combined stressors; however, the expression of UCP1, HKT1, and PIP2;1 transcripts was slightly enhanced. These data show that 2-OHMel alleviates the effects of simultaneous abiotic stressors via the actions of multiple TFs, including Myb4 and AP37.

Cloning and functional characterization of the Arabidopsis N-acetylserotonin O-methyltransferase responsible for melatonin synthesis.

The N-acetylserotonin O-methyltransferase (ASMT) gene encodes the enzyme that catalyzes the conversion of N-acetylserotonin to melatonin as the last step in melatonin biosynthesis. The first plant ASMT gene to be cloned was from rice. An orthologous gene encoding a protein with ASMT activity and only 39.7% amino acid sequence identity to the rice ASMT protein was recently isolated from apple (Malus zumi). The low homology of the apple ASMT sequence prompted us to screen the Arabidopsis genome for a homologous ASMT gene. The At4g35160 gene exhibited the highest sequence identity (31%) to the rice ASMT gene, followed by the At1g76790 gene with 29% sequence identity. We purified recombinant proteins expressed from the two Arabidopsis genes. The At4g35160 recombinant protein exhibited ASMT enzyme activity, but the At1g76790 recombinant protein did not; thus, we designated At4g35160 as an Arabidopsis thaliana ASMT (AtASMT) gene. The AtASMT protein catalyzed the conversion of N-acetylserotonin to melatonin and serotonin to 5-methoxytryptamine with Vmax values of 0.11 and 0.29 pkat/mg protein, respectively. However, AtASMT exhibited no caffeic acid O-methyltransferase activity, suggesting that its function was highly specific to melatonin synthesis. AtASMT transcripts were induced by cadmium treatment in Arabidopsis followed by increased melatonin synthesis. Similar to other ASMT proteins, AtASMT was localized in the cytoplasm and its ectopic overexpression in rice resulted in increased ASMT enzyme activity and melatonin production, indicating the involvement of AtASMT in melatonin synthesis.

Neonatal outcomes of twin pregnancies delivered at late-preterm versus term gestation based on chorionicity and indication for delivery.

OBJECTIVE: To investigate the neonatal outcomes of twin pregnancies delivered at late-preterm versus term gestation based on chorionicity and indication for delivery. STUDY DESIGN: This is a retrospective cohort study of women with twin pregnancies delivered at ≥34 weeks of gestation from 1995 to 2014. Subjects were categorized into two groups according to gestational age at delivery: late-preterm group (34-36 weeks) and term group (≥37 weeks). Neonatal outcome measures including neonatal intensive care unit (NICU) admission, mechanical ventilator support, and respiratory distress syndrome (RDS) were compared between the late-preterm and term group based on chorionicity (monochorionic or dichorionic) and delivery indication (elective or non-elective). RESULTS: A total of 1198 twin pregnancies were included in the study: 679 in the late-preterm group and 519 in the term group. Late-preterm twin infants had higher rates of NICU admission, mechanical ventilator support, and RDS than did term twin infants, regardless of the chorionicity and indication for delivery. In the multivariable analysis, late-preterm birth, monochorionicity, and non-elective delivery were independently associated with a significantly higher risk of NICU admission and mechanical ventilator support. CONCLUSION: The late-preterm birth was associated with a higher risk of adverse neonatal outcome regardless of chorionicity and indication for delivery, and showed significantly increased risk by monochorionicity and non-elective delivery.

BrUGE1 transgenic rice showed improved growth performance with enhanced drought tolerance.

UDP-glucose 4-epimerase (UGE) catalyzes the reversible conversion of UDP-glucose to UDP-galactose. To understand the biological function of UGE from Brassica rapa, the gene BrUGE1 was cloned and introduced into the genome of wild type rice 'Gopum' using the Agrobacterium-mediated transformation method. Four lines which carried a single copy gene were selected and forwarded to T3 generation. Agronomic traits evaluation of the transgenic T3 lines (CB01, CB03, and CB06) under optimal field conditions revealed enriched biomass production particularly in panicle length, number of productive tillers, number of spikelets per panicle, and filled spikelets. These remarkably improved agronomic traits were ascribed to a higher photosynthetic rate complemented with higher CO2 assimilation. Transcripts of BrUGE1 in transgenic lines continuously accumulated at higher levels after the 20% PEG6000 treatment, implying its probable role in drought stress regulation. This was paralleled by rapid accumulation of soluble sugars which act as osmoprotectants, leading to delayed leaf rolling and drying. Our findings suggest the potential of BrUGE1 in improving rice growth performance under optimal and water deficit conditions.

Development of an antibody-based diagnostic method for the identification of Bemisia tabaci biotype B.

The whitefly Bemisia tabaci is a very destructive pest. B. tabaci is composed of various morphologically undistinguishable biotypes, among which biotypes B and Q, in particular, draw attention because of their wide distribution in Korea and differential potentials for insecticide resistance development. To develop a biotype-specific protein marker that can readily distinguishes biotypes B from other biotypes in the field, we established an ELISA protocol based on carboxylesterase 2 (COE2), which is more abundantly expressed in biotypes B compared with Q. Recombinant COE2 was expressed, purified and used for antibody construction. Polyclonal antibodies specific to B. tabaci COE2 [anti-COE2 pAb and deglycosylated anti-COE2 pAb (DG anti-COE2 pAb)] revealed a 3-9-fold higher reactivity to biotype B COE2 than biotype Q COE2 by Western blot and ELISA analyses. DG anti-COE2 pAb exhibited low non-specific activity, demonstrating its compatibility in diagnosing biotypes. Western blot and ELISA analyses determined that one of the 11 field populations examined was biotype B and the others were biotype Q, suggesting the saturation of biotype Q in Korea. DG anti-COE2 pAb discriminates B. tabaci biotypes B and Q with high specificity and accuracy and could be useful for the development of a B. tabaci biotype diagnosis kit for on-site field applications.

Coordinated regulation of melatonin synthesis and degradation genes in rice leaves in response to cadmium treatment.

We investigated the expression patterns of genes involved in melatonin synthesis and degradation in rice leaves upon cadmium (Cd) treatment and the subcellular localization sites of melatonin 2-hydroxylase (M2H) proteins. The Cd-induced synthesis of melatonin coincided with the increased expression of melatonin biosynthetic genes including tryptophan decarboxylase (TDC), tryptamine 5-hydroxylase (T5H), and N-acetylserotonin methyltransferase (ASMT). However, the expression of serotonin N-acetyltransferase (SNAT), the penultimate gene in melatonin biosynthesis, was downregulated, suggesting that melatonin synthesis was counter-regulated by SNAT. Notably, the induction of melatonin biosynthetic gene expression was coupled with the induction of four M2H genes involved in melatonin degradation, which suggests that genes for melatonin synthesis and degradation are coordinately regulated. The induced M2H gene expression was correlated with enhanced M2H enzyme activity. Three of the M2H proteins were localized to the cytoplasm and one M2H protein was localized to chloroplasts, indicating that melatonin degradation occurs both in the cytoplasm and in chloroplasts. The biological activity of 2-hydroxymelatonin in the induction of the plant defense gene expression was 50% less than that of melatonin, which indicates that 2-hydroxymelatonin may be a metabolite of melatonin. Overall, our data demonstrate that melatonin synthesis occurs in parallel with melatonin degradation in both chloroplasts and cytoplasm, and the resulting melatonin metabolite 2-hydroxymelatonin also acts as a signaling molecule for defense gene induction.

Paecilomycies japonica reduces repeated nicotine-induced neuronal and behavioral activation in rats.

BACKGROUND: Many studies have demonstrated that repeated injections of nicotine can produce progressive increases in locomotor activity and enhanced expression of c-fos and tyrosine hydroxylase (TH) in brain dopaminergic areas. Paecilomyces japonica (PJ) is a herbal medicine that is commonly used to treat opiate and other addictions in Eastern Asia. However, its influence on nicotine addiction has not been examined. This study was carried out to investigate the effects of PJ on repeated nicotine-induced behavioral sensitization of locomotor activity and c-Fos and TH expression in the rat brain using immunohistochemistry. METHODS: Rats were pretreated with PJ (10, 25, 50, 100, and 200 mg/kg, intraperitoneally) 30 min before repeated injections of nicotine (0.4 mg/kg, subcutaneously, twice daily for 7 days). Locomotor activity was measured in rats during 7-day nicotine treatments. On the seventh day, c-Fos and TH expression were assessed. RESULTS: Pretreatment with PJ decreased the development of nicotine-induced sensitization, c-Fos expression in the nucleus accumbens and striatum, and TH expression in the ventral tegmental area. PJ decreased nicotine-induced locomotor activity by modulating brain dopaminergic systems. CONCLUSION: The results of the present study suggest that PJ may be a useful agent for preventing and treating nicotine addiction.

Lack of Globulin Synthesis during Seed Development Alters Accumulation of Seed Storage Proteins in Rice.

The major seed storage proteins (SSPs) in rice seeds have been classified into three types, glutelins, prolamins, and globulin, and the proportion of each SSP varies. It has been shown in rice mutants that when either glutelins or prolamins are defective, the expression of another type of SSP is promoted to counterbalance the deficit. However, we observed reduced abundances of glutelins and prolamins in dry seeds of a globulin-deficient rice mutant (Glb-RNAi), which was generated with RNA interference (RNAi)-induced suppression of globulin expression. The expression of the prolamin and glutelin subfamily genes was reduced in the immature seeds of Glb-RNAi lines compared with those in wild type. A proteomic analysis of Glb-RNAi seeds showed that the reductions in glutelin and prolamin were conserved at the protein level. The decreased pattern in glutelin was also significant in the presence of a reductant, suggesting that the polymerization of the glutelin proteins via intramolecular disulfide bonds could be interrupted in Glb-RNAi seeds. We also observed aberrant and loosely packed structures in the storage organelles of Glb-RNAi seeds, which may be attributable to the reductions in SSPs. In this study, we evaluated the role of rice globulin in seed development, showing that a deficiency in globulin could comprehensively reduce the expression of other SSPs.

Seroprevalence of Trichinella sp. in Wild Boars (Sus scrofa) from Yanggu-gun, Gangwon-do, Korea.

A total 7 outbreaks of trichinellosis have occurred in Korea, mostly as a result of consumption of raw wild boar (Sus scrofa) meat. Since only 1 serological survey on wild boars had yet been performed in Korea, the present study aimed to estimate the prevalence of trichinellosis in wild boars and some species of rodents by artificial digestion and serological examinations in Yanggu-gun, Gangwon-do, the endemic area of trichinellosis. Both the wild boar and rodent muscle samples revealed no Trichinella larvae by direct examination and artificial digestion method. However, serological examinations revealed that 4 wild boar sera samples out of 118 (3.4%) were positive to Trichinella antigen. Although the recovery of Trichinella larvae ended in a failure, it is proved for the first time that the sylvatic cycle of Trichinella has been maintained in wild boars of Gangwon-do, Korea.

Increased expression of Fe-chelatase leads to increased metabolic flux into heme and confers protection against photodynamically induced oxidative stress.

Fe-chelatase (FeCh, EC 4.99.1.1) inserts Fe(2+) into protoporphyrin IX (Proto IX) to form heme, which influences the flux through the tetrapyrrole biosynthetic pathway as well as fundamental cellular processes. In transgenic rice (Oryza sativa), the ectopic expression of Bradyrhizobium japonicum FeCh protein in cytosol results in a substantial increase of FeCh activity compared to wild-type (WT) rice and an increasing level of heme. Interestingly, the transgenic rice plants showed resistance to oxidative stress caused not only by the peroxidizing herbicide acifluorfen (AF) as indicated by a reduced formation of leaf necrosis, a lower conductivity, lower malondialdehyde and H2O2 contents as well as sustained Fv/Fm compared to WT plants, but also by norflurazon, paraquat, salt, and polyethylene glycol. Moreover, the transgenic plants responded to AF treatment with markedly increasing FeCh activity. The accompanying increases in heme content and heme oxygenase activity demonstrate that increased heme metabolism attenuates effects of oxidative stress caused by accumulating porphyrins. These findings suggest that increases in heme levels and porphyrin scavenging capacity support a detoxification mechanism serving against porphyrin-induced oxidative stress. This study also implicates heme as possibly being a positive signal in plant stress responses.