Expression of a Structural Protein of the Mycovirus FgV-ch9 Negatively Affects the Transcript Level of a Novel Symptom Alleviation Factor and Causes Virus Infection-Like Symptoms in Fusarium graminearum.

Infections of fungi by mycoviruses are often symptomless but sometimes also fatal, as they perturb sporulation, growth, and, if applicable, virulence of the fungal host. Hypovirulence-inducing mycoviruses, therefore, represent a powerful means to defeat fungal epidemics on crop plants. Infection with Fusarium graminearum virus China 9 (FgV-ch9), a double-stranded RNA (dsRNA) chrysovirus-like mycovirus, debilitates Fusarium graminearum, the causal agent of fusarium head blight. In search for potential symptom alleviation or aggravation factors in F. graminearum, we consecutively infected a custom-made F. graminearum mutant collection with FgV-ch9 and found a mutant with constantly elevated expression of a gene coding for a putative mRNA-binding protein that did not show any disease symptoms despite harboring large amounts of virus. Deletion of this gene, named virus response 1 (vr1), resulted in phenotypes identical to those observed in the virus-infected wild type with respect to growth, reproduction, and virulence. Similarly, the viral structural protein coded on segment 3 (P3) caused virus infection-like symptoms when expressed in the wild type but not in the vr1 overexpression mutant. Gene expression analysis revealed a drastic downregulation of vr1 in the presence of virus and in mutants expressing P3. We conclude that symptom development and severity correlate with gene expression levels of vr1 This was confirmed by comparative transcriptome analysis, showing a large transcriptional overlap between the virus-infected wild type, the vr1 deletion mutant, and the P3-expressing mutant. Hence, vr1 represents a fundamental host factor for the expression of virus-related symptoms and helps us understand the underlying mechanism of hypovirulence.IMPORTANCE Virus infections of phytopathogenic fungi occasionally impair growth, reproduction, and virulence, a phenomenon referred to as hypovirulence. Hypovirulence-inducing mycoviruses, therefore, represent a powerful means to defeat fungal epidemics on crop plants. However, the poor understanding of the molecular basis of hypovirulence induction limits their application. Using the devastating fungal pathogen on cereal crops, Fusarium graminearum, we identified an mRNA binding protein (named virus response 1, vr1) which is involved in symptom expression. Downregulation of vr1 in the virus-infected fungus and vr1 deletion evoke virus infection-like symptoms, while constitutive expression overrules the cytopathic effects of the virus infection. Intriguingly, the presence of a specific viral structural protein is sufficient to trigger the fungal response, i.e., vr1 downregulation, and symptom development similar to virus infection. The advancements in understanding fungal infection and response may aid biological pest control approaches using mycoviruses or viral proteins to prevent future Fusarium epidemics.

Quality of life after multiple trauma: the effect of early onset psychotherapy on quality of life in trauma patients.

BACKGROUND AND AIMS: The aim of this study was to improve health-related quality of life (HRQOL) related to depression, anxiety, pain, physical functioning and social aspects for severely injured trauma survivors by early onset cognitive behavioural therapy applied on the surgical ward. MATERIALS AND METHODS: The study was a randomised, controlled study. Of 298 primary screened patients 171 were eligible and randomised. Ninety-two patients adhered to follow-up investigations at 6 and 12 months. Main outcome measure was a sum score according to O'Brien calculated of five different questionnaires (BDI, SF-36, STAI, SCL 90R, F-SOZU-22). RESULTS: The sum score for overall HRQOL did not show significant group differences at follow-up. Effects on HRQOL sub-dimensions within groups have been found. In the dimension of depression therapy group showed significant improvement from the first measurement to discharge from hospital (p < 0.001), 6 MFU (p = 0.004) and to 12 MFU (p = 0.013). Measures of anxiety showed significant improvement for the therapy group at discharge from hospital (p = 0.001). In the control group there was only a significant reduction in depression and anxiety from surgical ward to discharge (p = 0.013/p = 0.031). CONCLUSIONS: Early onset cognitive therapy is not effective in improving overall HRQOL of severely injured patients but shows promising effects on depression and anxiety up to 12 months after trauma.