siRNA quelling of tri4 and tri5 genes related to deoxynivalenol synthesis in Fusarium graminearum and Fusarium culmorum

Aim: This study was conducted to investigate the quelling of tri4 and tri5 genes associated with deoxynivalenol, most common class B trichothecene, via siRNA application. Methodology: In this study, one Fusarium graminearum (4F) and two F. culmorum (9F and 20F) isolates, expressing high levels of tri4 and tri5 genes, were targeted for siRNA-based silencing. Full length tri4 and tri5 genes were amplified from all isolates, sequenced and then subjected to CLUSTALW analysis for designing siRNA molecules. Totally designed six siRNAs were separately co-transfected together with helper plasmids (pEGFP75 and pAN7-1) as 36 combinations into protoplast cultures and quelling was analysed via real time polymerase chain reaction, thin layer chromatography and spectrofluorimetric analysis. Results: Alignment of both tri4 and tri5 genes’ sequencing revealed high levels of similarity between isolates (94-99% and 95-100%, respectively). Transfection efficiency ranged from 50±0.00/5x104 to 99.33±10.06/5x104 and relative fluorescence unit values were calculated between 1.37±0.07 and 2.89±0.06. The 0.7 kb length fragments of hph and GFP were amplified from transfectants. The real time PCR revealed that tri4 was completely suppressed in 30 experimental sets whereas down-regulations of tri5, ranging from 74.5 to 99%, was detected in remaining 6 experiment groups. Thin layer chromatography assay also showed that siRNA-transfected Fusarium samples showed no deoxynivalenol spots. Interpretation: This study revealed that tri4 and tri5 genes can be targeted in the development of less deoxynivalenol (DON)-producing strains through RNAi. Moreover, current study has great importance as it demonstrates that quelling can be used as a potential strategy in controlling diseases caused by phytopathogenic species.

A Case of Podostroma Cornu-Damae Intoxication Induced Pancytopenia and Skin Desquamation: Successful Treatment with Granulocyte Colony Stimulation Factor (G-CFS)

Podostroma cornu-damae is a rare species of fungus belonging to the Hyocreaceae family. Its fruit body is highly toxic, as it contains trichothecene mycotoxins. The morphology is similar to that of immature Ganoderma lucidum, making identification difficult for non-experts. We experienced such a case of a 56- year-old male who picked and consumed podostroma cornu-damae, and consumed. Later that day, he developed digestive system symptoms, including nausea, vomiting, and abdominal pain. He presented to the emergency room (ER), there were no abnormal physical findings, symptoms improved after gastric lavage, and the patient voluntarily discharged himself on the same day. The following day, as the symptoms gradually deteriorated, he was admitted via the ER. He was presented with severe pancytopenia, alopecia, desquamation of skin, and acute renal failure. He recovered without any complications after conservative care, antibiotics therapy, and granulocyte colony stimulating factor administration. The most commonly reported complications of podostroma cornu-damae intoxication were reported pancytopenia, infection, disseminated intravascular coagulation, acute renal failure, etc. since Prevention is especially important because its toxicity can be lethal and there is no particular treatment to date, prevention is especially important. Promotion and education for the public are needed.

A Case of Podostroma Cornu-Damae Intoxication Similar to Drug Hypersensitivity Syndrome / 대한내과학회지

The clinical aspects of intoxication can be similar to those of drug hypersensitivity syndrome, including desquamation, hematologic abnormalities, multiple organ failure, and even death. Many people consume mushrooms that they collect in the mountains, and consequently, the incidence of poisonous mushroom intoxication is increasing. Podostroma cornu-damae is a poisonous mushroom not well-known to the public that contains trichothecene, a deadly poison. It is difficult to differentiate P. cornu-damae from other edible mushrooms, especially young Ganoderma lucidum. Therefore, the general public should be aware of the dangers of indiscreet ingestion of mushrooms. When physicians treat patients presenting clinical symptoms similar to those of drug hypersensitivity reaction following the intake of mushrooms, poisonous mushroom intoxication must be taken into consideration. We report this case together with a literature review, as we experienced one P. cornu-damae intoxication case showing similar clinical aspects to drug hypersensitivity syndrome.