Comparison of post-treatment recurrence between ranibizumab injection and laser photocoagulation for type 1 retinopathy of prematurity.

OBJECTIVE: To compare post-treatment recurrence between ranibizumab injection and laser photocoagulation (LP) for type 1 retinopathy of prematurity (ROP), and explore the associated risk factors. METHODS: The clinical data of ROP infants treated with LP or ranibizumab in a NICU of China from October 2007 to November 2021 were retrospectively analyzed and compared, such as general condition, degree of ROP, therapeutic effectiveness and post-treatment recurrence. The dependent variable was recurrence after ROP treatment. Univariate and regression analysis of risk factors was performed. RESULTS: Of the 298 ROP infants (556 eyes), 58% of the eyes were treated with LP and the other 42% with ranibizumab. There was no significant difference in gestational age at birth, birth weight, sex, delivery mode, prenatal corticosteroids, ROP diagnosed before admission or after admission, and the duration of oxygen therapy between the two groups. However, the ratio of type 1 ROP and aggressive retinopathy of prematurity (A-ROP) in ranibizumab group was higher than that in LP group. The number of treatments, recurrence rate and recurrence interval in ranibizumab group were higher than those in LP group. However, there was no difference in the recurrence rate between the two groups after stratified analysis by the lesion area and the presence or absence of A-ROP. There was no significant difference in the final lesion regression between the two groups. Regression analysis showed that plus disease and ROP located in zone I were independent risk factors for post-treatment recurrence. CONCLUSION: There is no significant difference in the recurrence rate of ROP between ranibizumab injection and LP, and recurrence is mainly related to the severity of ROP. In half of our patients treated with A-ROP recurrences occur.

Complete nucleotide sequence of jasmine virus H, a new member of the family Tombusviridae.

Jasmine virus H (JaVH) is a novel virus associated with symptoms of yellow mosaic on jasmine. The JaVH genome is 3,867 nt in length with five open reading frames (ORFs) encoding a 27-kDa protein (ORF 1), an 87-kDa replicase protein (ORF 2), two centrally located movement proteins (ORF 3 and 4), and a 37-kDa capsid protein (ORF 5). Based on genomic and phylogenetic analysis, JaVH is predicted to be a member of the genus Pelarspovirus in the family Tombusviridae.

The small GTPase MoYpt7 is required for membrane fusion in autophagy and pathogenicity of Magnaporthe oryzae.

Rab GTPases are required for vesicle-vacuolar fusion during vacuolar biogenesis in fungi. To date, little is known about the biological functions of the Rab small GTPase components in Magnaporthe oryzae. In this study, we investigated MoYpt7 of M. oryzae, a homologue of the small Ras-like GTPase Ypt7 in Saccharomyces cerevisiae. Cellular localization assays showed that MoYpt7 was predominantly localized to vacuolar membranes. Using a targeted gene disruption strategy, a ΔMoYPT7 mutant was generated that exhibited defects in mycelial growth and production of conidia. The conidia of the ΔMoYPT7 mutant were malformed and defective in the formation of appressoria. Consequently, the ΔMoYPT7 mutant failed to cause disease in rice and barley. Furthermore, the ΔMoYPT7 mutant showed impairment in autophagy, breached cell wall integrity, and higher sensitivity to both calcium and heavy metal stress. Transformants constitutively expressing an active MoYPT7 allele (MoYPT7-CA, Gln67Leu) exhibited distinct phenotypes from the ΔMoYPT7 mutant. Expression of MoYPT7-CA in MoYpt7 reduced pathogenicity and produced more appressoria-forming single-septum conidia. These results indicate that MoYPT7 is required for fungal morphogenesis, vacuole fusion, autophagy, stress resistance and pathogenicity in M. oryzae.

Stress signaling in response to polycyclic aromatic hydrocarbon exposure in Arabidopsis thaliana involves a nucleoside diphosphate kinase, NDPK-3.

MAIN CONCLUSION: The study is the first to reveal the proteomic response in plants to a single PAH stress, and indicates that NDPK3 is a positive regulator in the Arabidopsis response to phenanthrene stress. Polycyclic aromatic hydrocarbons (PAHs) are highly carcinogenic pollutants that are byproducts of carbon-based fuel combustion, and tend to persist in the environment for long periods of time. PAHs elicit complex, damaging responses in plants, and prior research at the physiological, biochemical, and transcriptional levels has indicated that reactive oxygen species (ROS) and oxidative stress play major roles in the PAH response. However, the proteomic response has remained largely unexplored. This study hypothesized that the proteomic response in Arabidopsis thaliana to phenanthrene, a model PAH, would include a strong oxidative stress signature, and would provide leads to potential signaling molecules involved. To explore that proteomic signature, we performed 2D-PAGE experiments and identified 30 proteins levels that were significantly altered including catalases (CAT), ascorbate peroxidase (APX), peroxiredoxins (POD), glutathione-S-transferase, and glutathione reductase. Also upregulated was nucleoside diphosphate kinase 3 (NDPK-3), a protein known to have metabolic and stress signaling functions. To address whether NDPK-3 functions upstream of the oxidative stress response, we measured levels of stress-responsive enzymes in NDPK-3 overexpressor, loss-of-function knockout, and wild-type plant lines. In the NDPK-3 overexpressor, the enzyme activities of APX, CAT, POD, as well as superoxide dismutase were all increased compared to wild type; in the NDPK-3 knockout line, these enzymes had reduced activity. This pattern occurred in untreated as well as phenanthrene-treated plants. These data support a model in which NDPK-3 is a positive regulator of the Arabidopsis stress response to PAHs.

Development and application of the Chinese version of the adult strabismus quality of life questionnaire (AS-20): a cross-sectional study.

BACKGROUND: Patients with strabismus experience visual dysfunction, self-image disorders, low self-esteem, and social and emotional barriers, which adversely influence their health-related quality of life (HRQoL). Currently no strabismus-specific questionnaire is available in China to identify patients' quality of life and to evaluate the effectiveness of strabismus treatment. The aims of the present study were to validate the Chinese-language version of the Adult Strabismus Quality of Life Questionnaire (AS-20) and to evaluate the impacts of strabismus on the quality of life among Chinese strabismus patients. METHODS: Two hundred and fifty-five Chinese adults with strabismus, one hundred visually normal adults and one hundred patients with other eye diseases completed the Chinese version of AS-20. Psychometric properties of the Chinese AS-20 were examined by Cronbach's α coefficient, test-retest and split-half reliability, and construct and criterion-related validity. Independent-samples t test and one-way ANOVA analyses were conducted to explore the impact of demographic factors and clinical characteristics on HRQoL in Chinese strabismic adults. RESULTS: The final AS-20 in Chinese (AS-C) included 18 items and two subscales: psychosocial (12 items) and function (6 items). The Cronbach's α was 0.908 for overall scale, with 0.913 and 0.808 for 'psychosocial' and 'function' subscales respectively, indicating high internal consistency reliability. The mean of the overall AS-C score among strabismus patients was 62.80 ± 18.94, significantly lower than that in visually normal adults (t = -18.693, P < 0.001), and in patients with other eye diseases (t = -5.512, P < 0.001). CONCLUSIONS: The AS-C is a culturally appropriate tool to evaluate the HRQoL in Chinese strabismus adults. The psychosocial health well-being and overall quality of life in strabismic patients should receive greater emphasis.

[Retinopathy of prematurity screening in 2185 premature infants].

OBJECTIVE: To determine the incidence and risk factors of retinopathy of prematurity (ROP) among premature infants. METHODS: The fundus examination data of 2185 cases of premature infants [birth body weight ≤ 2000 g or gestational age (GA) ≤ 34 weeks] in neonatal intensive care unit of Bayi Children's Hospitals in Beijing between January 2009 and December 2010 were collected and retrospectively analyzed. RESULTS: Of 2185 cases of premature infants (1571 had used supplemental oxygen) received RetCam-II ophthalmoscopy screening, 287 cases developed ROP with the incidence of 13.1% according to the international classification of ROP (ICROP), including 34 cases (11.9%) suffering from zone I, 147 cases (51.2%) from zone II, and 106 cases (36.9%) from zone III. Stage 1, 2 and 3 lesions were 117 cases, 142 cases and 28 cases, accounting for 40.8%, 49.5% and 9.7%, respectively, while stage 4 and stage 5 lesions were not found. Thirty-six cases developed plus disease, accounting for 12.5%. Between ROP and Non-ROP groups, there were significant differences in birth weight (1269.9 ± 380.0) g vs (1479.7 ± 359.3) g vs (1633.9 ± 352.3) g, gestational age (30.6 ± 2.0) g vs (32.4 ± 1.8) W and time of supplemental oxygen [Median 10 d (0 to 71 d) vs 2 d (0 to 36 d)]. Among zone I, II and III groups, there were significant differences in birth weight (1269.9 ± 380.0) g vs (1479.7 ± 359.3) g vs (1633.9 ± 352.3) g, gestational age (29.3 ± 2.2) W vs (30.5 ± 1.9) W vs (31.2 ± 1.8) W and time of supplemental oxygen[Median 14 d (0 to 52 d)vs 10 d (0 to 71 d) vs 8 d (0 to 52 d)] (χ(2) = 257.5, 371.7, 6.695; P < 0.05), while among stage 1, 2 and 3 groups, there were also significant differences in birth weight (1593.3 ± 413.7) g vs (1481.3 ± 336.7) g vs (1325.3 ± 313.7) g, gestational age (30.9 ± 2.0) W vs (30.6 ± 1.9) W vs (29.5 ± 1.7) W and time of supplemental oxygen [Median 8 d (0 to 52 d) vs 11 d (0 to 65 d) vs 12 d (0 to 71 d)] (χ(2) = 230.8, 273.5, 6.695; P < 0.05). In 1004 cases admitted in 2009, 150 developed ROP with the incidence of 14.9%; while in 1181 cases admitted in 2010, 137 developed ROP with the incidence of 11.6%. There was significant differences in the incidence of ROP between these two years (χ(2) = 5.305, P < 0.05). Thirty-eight infants (1.7%) received laser therapy and only 3 infants progressed to stage 4 after laser therapy. Three infants with laser failed stopped progress after vasectomy. Finally, all patients were cured without blindness. CONCLUSIONS: Less birth weight, shorter GA and time of supplemental oxygen are close related to the development of ROP. It is necessary to pay high attention to the screen on premature infants with smaller gestation age, lower birth weight or using oxygen for the reduction or even avoid of blindness.

Mitochondrial Genome Contributes to the Thermal Adaptation of the Oomycete Phytophthora infestans.

As a vital element of climate change, elevated temperatures resulting from global warming present new challenges to natural and agricultural sustainability, such as ecological disease management. Mitochondria regulate the energy production of cells in responding to environmental fluctuation, but studying their contribution to the thermal adaptation of species is limited. This knowledge is needed to predict future disease epidemiology for ecology conservation and food security. Spatial distributions of the mitochondrial genome (mtDNA) in 405 Phytophthora infestans isolates originating from 15 locations were characterized. The contribution of MtDNA to thermal adaptation was evaluated by comparative analysis of mtDNA frequency and intrinsic growth rate, relative population differentiation in nuclear and mtDNA, and associations of mtDNA distribution with local geography climate conditions. Significant variation in frequency, intrinsic growth rate, and spatial distribution was detected in mtDNA. Population differentiation in mtDNA was significantly higher than that in the nuclear genome, and spatial distribution of mtDNA was strongly associated with local climatic conditions and geographic parameters, particularly air temperature, suggesting natural selection caused by a local temperature is the main driver of the adaptation. Dominant mtDNA grew faster than the less frequent mtDNA. Our results provide useful insights into the evolution of pathogens under global warming. Given its important role in biological functions and adaptation to local air temperature, mtDNA intervention has become an increasing necessity for future disease management. To secure ecological integrity and food production under global warming, a synergistic study on the interactive effect of changing temperature on various components of biological and ecological functions of mitochondria in an evolutionary frame is urgently needed.

Corrigendum: Mitochondrial genome contributes to the thermal adaptation of the oomycete Phytophthora infestans.

[This corrects the article DOI: 10.3389/fmicb.2022.928464.].

Multiple Mechanisms Drive the Evolutionary Adaptation of Phytophthora infestans Effector Avr1 to Host Resistance.

Effectors, a group of small proteins secreted by pathogens, play a central role in antagonistic interactions between plant hosts and pathogens. The evolution of effector genes threatens plant disease management and sustainable food production, but population genetic analyses to understand evolutionary mechanisms of effector genes are limited compared to molecular and functional studies. Here we investigated the evolution of the Avr1 effector gene from 111 Phytophthora infestans isolates collected from six areas covering three potato cropping regions in China using a population genetic approach. High genetic variation of the effector gene resulted from diverse mechanisms including base substitution, pre-termination, intragenic recombination and diversifying selection. Nearly 80% of the 111 sequences had a point mutation in the 512th nucleotide (T512G), which generated a pre-termination stop codon truncating 38 amino acids in the C-terminal, suggesting that the C-terminal may not be essential to ecological and biological functions of P. infestans. A significant correlation between the frequency of Avr1 sequences with the pre-termination and annual mean temperature in the collection sites suggests that thermal heterogeneity might be one of contributors to the diversifying selection, although biological and biochemical mechanisms of the likely thermal adaptation are not known currently. Our results highlight the risk of rapid adaptation of P. infestans and possibly other pathogens as well to host resistance, and the application of eco-evolutionary principles is necessary for sustainable disease management in agricultural ecosystems.

Effector Avr4 in Phytophthora infestans Escapes Host Immunity Mainly Through Early Termination.

Effector genes play critical roles in the antagonistic interactions between plants and pathogens. However, knowledge of mutation mechanisms and evolutionary processes in effector genes and the contribution of climatic factors to the evolution of effector genes are fragmented but important in sustainable management of plant diseases and securing food supply under changing climates. Here, we used a population genetic approach to explore the evolution of the Avr4 gene in Phytophthora infestans, the causal agent of potato blight. We found that the Avr4 gene exhibited a high genetic diversity generated by point mutation and sequence deletion. Frameshifts caused by a single base-pair deletion at the 194th nucleotide position generate two stop codons, truncating almost the entire C-terminal, which is important for effector function and R4 recognition in all sequences. The effector is under natural selection for adaptation supported by comparative analyses of population differentiation (FST ) and isolation-by-distance between Avr4 sequences and simple sequence repeat marker loci. Furthermore, we found that local air temperature was positively associated with pairwise FST in the Avr4 sequences. These results suggest that the evolution of the effector gene is influenced by local air temperature, and the C-terminal truncation is one of the main mutation mechanisms in the P. infestans effector gene to circumvent the immune response of potato plants. The implication of these results to agricultural and natural sustainability in future climate conditions is discussed.

Evidence for a synergistic effect of post-translational modifications and genomic composition of eEF-1α on the adaptation of Phytophthora infestans.

Genetic variation plays a fundamental role in pathogen's adaptation to environmental stresses. Pathogens with low genetic variation tend to survive and proliferate more poorly due to their lack of genotypic/phenotypic polymorphisms in responding to fluctuating environments. Evolutionary theory hypothesizes that the adaptive disadvantage of genes with low genomic variation can be compensated for structural diversity of proteins through post-translation modification (PTM) but this theory is rarely tested experimentally and its implication to sustainable disease management is hardly discussed. In this study, we analyzed nucleotide characteristics of eukaryotic translation elongation factor-1α (eEF-lα) gene from 165 Phytophthora infestans isolates and the physical and chemical properties of its derived proteins. We found a low sequence variation of eEF-lα protein, possibly attributable to purifying selection and a lack of intra-genic recombination rather than reduced mutation. In the only two isoforms detected by the study, the major one accounted for >95% of the pathogen collection and displayed a significantly higher fitness than the minor one. High lysine representation enhances the opportunity of the eEF-1α protein to be methylated and the absence of disulfide bonds is consistent with the structural prediction showing that many disordered regions are existed in the protein. Methylation, structural disordering, and possibly other PTMs ensure the ability of the protein to modify its functions during biological, cellular and biochemical processes, and compensate for its adaptive disadvantage caused by sequence conservation. Our results indicate that PTMs may function synergistically with nucleotide codes to regulate the adaptive landscape of eEF-1α, possibly as well as other housekeeping genes, in P. infestans. Compensatory evolution between pre- and post-translational phase in eEF-1α could enable pathogens quickly adapting to disease management strategies while efficiently maintaining critical roles of the protein playing in biological, cellular, and biochemical activities. Implications of these results to sustainable plant disease management are discussed.

Microbial community associated with ectomycorrhizal Russula symbiosis and dominated nature areas in southern China.

Russula griseocarnosa is one of the uncultivable important mycorrhizal edible fungi. Currently, there is a limited insight into the dynamic composition of the microbial communities associated with Russula. Here, the microbiota in the root and mycorrhizosphere from Russula-Fagaceae nature areas of Fujian province were identified by Illumina MiSeq high-throughput sequencing. First, we compared three types of fungal communities associated with Russula-Fagaceae root mycelia-running stage (stage-1), Russula sporocarping stage-2 (stage-2) and Russula-free Fagaceae root (stage-3). Fungal diversity negatively correlated with Russula. Russula, Tomentella and Lactarius were core EcM in Fagaceae roots. A total of eight genera, including Boletus, are likely a positive indicator of Russula sporocarp production in Russula-Fagaceae roots, while Tomentella and Elaphomyces for Russula symbiosis. Secondly, analysis of fungal and bacterial communities within rhizosphere soils from the three stages revealed six genera, including Dacryobolus and Acidocella, as possible indicator species associated with sporocarping in Russula. Elaphomyces, Tomentella, Sorangium, Acidicaldus, Acidobacterium and Haliangium occurred more frequently in the Russula rhizosphere. Furthermore, operational taxonomic unit (OTU) network analysis showed a positive correlation between Russula,Tomentella, Elaphomyces and Sorangium. Overall, our results revealed a relationship between micro-community and Russula, which may provide a new strategy for improving Russula symbiosis and sporocarp production.

A conserved double-W box in the promoter of CaWRKY40 mediates autoregulation during response to pathogen attack and heat stress in pepper.

CaWRKY40 was previously found to be transcriptionally up-regulated by Ralstonia solanacearum inoculation (RSI) or heat stress (HS), but the underlying mechanism remains unknown. Herein, we report that a double-W box-element (DWE) in the promoter of CaWRKY40 is critical for these responses. The upstream W box unit WI of this composite element is crucial for preferential binding by CaWRKY40 and responsiveness to RSI or HS. DWE-driven CaWRKY40 can be transcriptionally and nonspecifically regulated by itself and by CaWRKY58 and CaWRKY27. The DWE was also found in the promoters of CaWRKY40 orthologs, including AtWRKY40, VvWRKY40, GmWRKY40, CplWRKY40, SaWRKY40, SpWRKY40, NtWRKY40, and NaWRKY40. DWEAtWRKY40 was analogous to DWECaWRKY40 by responding to RSI or HS and AtWRKY40 expression. These data suggest that a conserved response of plants to pathogen infection or HS is probably mediated by binding of the DWE by WRKY40.

[Bedside treatment of retinopathy of prematurity by laser photocoagulation].

OBJECTIVE: To study the efficacy of bedside treatment by laser photocoagulation for retinopathy of prematurity (ROP) in preterm infants hospitalized in the Neonatal Intensive Care Unit (NICU). METHODS: The clinical data of 30 cases of ROP who underwent peripheral laser ablation on bedside in the NICU from March to August 2009 were studied retrospectively. RESULTS: A total of 59 eyes from 30 patients received the laser therapy, with a total cure rate of 95%. According to the International Classification of ROP, 26 eyes of 13 infants had zone 1 disease, and 33 eyes of 17 infants had zone 2 disease. The birth gestational age and birth weight as well as corrected gestational age and corrected weight at operation in the zone 1 disease group were significantly lower than those in the zone 2 disease group. The number of laser spots in the zone 1 disease group was significantly higher than that in the zone 2 disease group. The cure rate in the zone 2 disease group (100%) was significantly higher than that in the zone 1 disease group (88%). CONCLUSIONS: Laser retinal photocoagulation on bedside in the NICU is effective for both zone 1 and zone 2 ROP. As compared with the infants with zone 2 disease, the infants with zone 1 disease may have a poor outcome.

Functional analysis of an alpha-1,2-mannosidase from Magnaporthe oryzae.

Identification of enzymes that are expressed during host colonization and characterization of their biochemical properties are prerequisite to understanding their role in the pathogen-host interaction. Nine alpha-1,2-mannosidase homologs were identified in the analysis of the Magnaporthe oryzae genome. Endoplasmic reticulum localized alpha-1,2-mannosidases play an important role in protein glycosylation. However, several members of the alpha-1,2-mannosidase gene family are predicted to be secreted. The biological role of such extracellular enzymes in host colonization has not been defined. Here, we characterized a secreted alpha-1,2-mannosidase of M. oryzae, MGG_00994.6, and found that the mature polypeptide is a glycoprotein capable of hydrolyzing alpha-1,2 linked mannobiose. The gene is expressed during growth in vitro and during colonization on rice plants, however, deletion of the gene did not affect pathogenicity. Five other members of the alpha-1,2-mannosidase of M. oryzae were expressed with a pattern similar to MGG_00994.6, suggesting the potential for functional redundancy. These results form the basis for additional studies on the role of this gene family in the rice blast fungus and its interaction with rice.

Isolation and identification of Sclerotinia stem rot causal pathogen in Arabidopsis thaliana.

A new stem rot disease is found to occur naturally on Arabidopsis plants in greenhouses of Fuzhou, China. In order to identify its pathogen, we conducted a series of fungal isolation and purification, plant reinoculation, and ascus and ascospore induction from the sclerotia. The isolate caused typical water-soaked lesions after reinoculation and produced sclerotia both on Arabidopsis plants and culture medium plates, and the sclerotia could be induced to produce discal apothecia and 8 binucleate ascospores per ascus. These disease symptom and fungal morphology data revealed that the fungus Sclerotinia sclerotiorum (Lib.) de Bary was the pathogen for Arabidopsis stem rot. To confirm this, we further amplified its large subunit ribosomal DNA (LSU rDNA) by polymerase chain reaction (PCR), and compared the sequence with the known LSU rDNA sequences in GenBank. The results show that the sequence shares the highest identities with the LSU rDNAs of different S. sclerotiorum strains. Taking all these data together, we concluded that the fungus that caused the Arabidopsis stem rot is S. sclerotiorum (Lib.) de Bary. This is the first report that Arabidopsis is naturally infected by S. sclerotiorum.

Effect of anti-VEGF treatment on retinopathy of prematurity in Zone II Stage 3.

AIM: To evaluate the effect of intravitreal ranibizumab injection for retinopathy of prematurity (ROP) in Zone II Stage 3+. METHODS: Data was collected for ROP patients with Zone II Stage 3+ who received intravitreal ranibizumab injections between October 2014 and Janu-ary 2017 at the Department of Ophthalmology in our hospital. No prior laser or other intravitreal treatment was done. Prior to the intervention and at each follow-up visit, fundus examination was performed. Gestational age at birth, sex, birth weight, ROP zone, ROP stage, post menstrual age (PMA) at treatment, and follow-up pe-riod were recorded. The final clinical status of the retina was evaluated for each patient. The primary outcome mea-sures included ROP recurrences requiring re-treatment, complete or incomplete peripheral vascularization. RESULTS: Eighty-six eyes of 46 premature infants with Zone II Stage 3+ ROP were enrolled in the study. The mean gestational age at birth was 28.18±1.67 (range: 25 to 33)wk and the mean birth weight was 1070.57±226.85 (range: 720.00 to 1650.00) g. The mean PMA at treatment was 38.32±2.99 (range: 32.29 to 46.00)wk. Seventy-one eyes (82.56%) were treated success-fully with intravitreal ranibizumab as monotherapy. Fifteen eyes (17.44%) developed recurrent disease. The mean interval between the treatment and retreatment was 5.96±3.22 (range: 1.86 to 11.71)wk. All eyes vascularized into zone III at the end of the study and among them 62 eyes (72.09%) achieved complete vascu-larization. CONCLUSION: Intravitreal ranibizumab injection is an effective treatment in Zone II Stage 3+ ROP patients. More patients with longer follow-up duration are necessary to confirm the safety and efficacy of this treatment.

A Putative Zn2Cys6 Transcription Factor Is Associated With Isoprothiolane Resistance in Magnaporthe oryzae.

Isoprothiolane (IPT), a systemic fungicide, has been applied to control rice blast since the 1970s. Although resistance to IPT has been observed, the mechanism of resistance still has not been fully elucidated. In this study, nucleotide polymorphisms were detected between two IPT-resistant mutants generated in the lab, and their parental wild type isolates using a whole-genome sequencing approach. In the genomes of the two resistant mutants, single point mutations were identified in a gene encoding a Zn2Cys6 transcription factor-like protein. Notably, either knocking out the gene or replacing the wild type allele with the mutant allele (R343W) in a wild type isolate resulted in resistance to IPT, indicating that the gene is associated with IPT resistance, and thus was designated as MoIRR (Magnaporthe oryzae isoprothiolane resistance related). Along with point mutations R343W in mutant 1a_mut, and R345C in 1c_mut, a 16 bp insertion in 6c_mut was also located in the Fungal_TF_MHR domain of MoIRR, revealing that this domain may be the core element for IPT resistance. In addition, IPT-resistant mutants and transformants showed cross-resistance with iprobenfos (IBP), which was consistent with previous observations. These results indicated that MoIRR is strongly connected to resistance to choline biosynthesis inhibitor (CBI), and further work should focus on investigating downstream effects of MoIRR.

Detection of deoxynivalenol based on a single-chain fragment variable of the antideoxynivalenol antibody.

Immunological detection of low molecular weight toxins, such as deoxynivalenol using single-chain antibody fragment (scFv), is a potentially novel and safe method of diagnosing fungal infection and food contamination. To develop a deoxynivalenol detection procedure based on scFv, deoxynivalenol was first conjugated to horseradish peroxidase (HRP) for immunoassay. Deoxynivalenol was initially activated using N-[p-maleimidophenyl] isocyanate and subsequently conjugated to S-acetyl thioglycolic acid N-hydroxysuccinimide-activated HRP. Sodium dodecylsulphate polyacrylamide gel electrophoresis and enzyme-linked immunosorbent assay (ELISA) analysis confirmed covalent attachment of deoxynivalenol to HRP successfully. Competitive direct-ELISA based on antideoxynivalenol scFv was used to detect deoxynivalenol in spiked and natural contaminated wheat samples, and the results showed that scFv is applicable in deoxynivalenol detection of contaminated wheat samples. This work confirms that sensitive and specific scFv against fungal toxins can be applicable in diagnosis of fungal infection.