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Vermeulen, J.

Publications and source records attributed to Vermeulen, J..

3 recordsLinked to original sources

Comparative genomics of Verticillium dahliae isolates reveals the in planta-secreted effector protein recognized in V2 tomato plants

Plant pathogens secrete effector molecules during host invasion to promote host colonization. However, some of these effectors become recognized by host receptors, encoded by resistance genes, to mount defense response and establish immunity. Recently, a novel resistance was identified in tomato, mediated by the single dominant V2 locus, to control strains of the soil-borne vascular wilt fungus Verticillium dahliae that belong to race 2. We performed comparative genomics between race 2 strains and resistance-breaking race 3 strains to identify the avirulence effector that activates V2 resistance, termed Av2. We identified 277 kb of race 2-specific sequence comprising only two genes that encode predicted secreted proteins, both of which are expressed by V. dahliae during tomato colonization. Subsequent functional analysis based on genetic complementation into race 3 isolates confirmed that one of the two candidates encodes the avirulence effector Av2 that is recognized in V2 tomato plants. The identification of Av2 will not only be helpful to select tomato cultivars that are resistant to race 2 strains of V. dahliae, as the corresponding V2 resistance gene has not yet been mapped, but also to monitor adaptations in the V. dahliae population to deployment of V2-containing tomato cultivars in agriculture.

plant biology↗

Smoking and the risk for bipolar disorder: causal evidence from a bidirectional Mendelian randomization study

ImportanceThere is increasing evidence that smoking is a risk factor for severe mental illness, including bipolar disorder. Conversely, patients with bipolar disorder might smoke more (often) as a result of the psychiatric disorder. Research that investigates causality and the direction of the relationship between smoking and bipolar disorder has been lacking.\n\nObjectiveTo investigate the direction and causal nature of the relationship between smoking and bipolar disorder we conducted a bidirectional Mendelian randomization (MR) study.\n\nData sourcesPublicly available summary statistics from genome-wide association studies on bipolar disorder, smoking initiation, smoking heaviness, smoking cessation and lifetime smoking (i.e., a compound measure of heaviness, duration and cessation). We applied multiple analytical methods with different, orthogonal assumptions to triangulate results, including inverse-variance weighted (IVW), MR-Egger or Egger SIMEX, weighted median, weighted mode, and Steiger filtered analyses.\n\nResultsAcross different methods of MR, consistent evidence was found for a positive effect of smoking on the odds of bipolar disorder (smoking initiation ORIVW=1.46, 95% CI=1.28-1.66, P=1.44x10-8, lifetime smoking ORIVW=1.72, 95% CI=1.29-2.28, P=1.8x10-4). The MR analyses of the liability of bipolar disorder on smoking provided no clear evidence of a strong causal effect (smoking initiation betaIVW= -0.008, 95% CI= -0.026-0.009, P=0.35; P=0.94; smoking heaviness betaIVW=0.028, 95% CI= 0.003-0.053, P=2.9x10-2; smoking cessation ORIVW= 0.997, 95% CI= 0.981-1.014, P=0.74; lifetime smoking betaIVW= -0.001, 95%CI=-0.022-0.020, P=0.95).\n\nConclusionsThese findings suggest that smoking initiation and lifetime smoking are likely to be a causal risk factor for developing bipolar disorder. We found some evidence that liability to smoking increased smoking heaviness. Given that smoking is a modifiable risk factor, these findings further support investment into smoking prevention and treatment in order to reduce mental health problems in future generations.

neuroscience↗

Circulating microRNA biomarkers for metastatic disease in neuroblastoma patients

In this study, the circulating miRNome from diagnostic neuroblastoma serum was assessed for identification of non-invasive biomarkers with potential in monitoring metastatic disease. After determining the circulating neuroblastoma miRNome, 743 miRNAs were screened in two independent cohorts of 131 and 54 patients. Evaluation of serum miRNA variance in a model testing for tumor stage, MYCN status, age at diagnosis and overall survival, revealed tumor stage as the most significant factor impacting miRNA abundance in neuroblastoma serum. Differential expression analysis between patients with metastatic and localized disease revealed 9 miRNAs strongly associated with metastatic stage 4 disease in both patient cohorts. Increasing levels of these miRNAs were also observed in serum from xenografted mice bearing human neuroblastoma tumors. Moreover, murine serum miRNA levels were strongly associated with tumor volume, suggesting this miRNA signature may be applied to monitor disease burden.

cancer biology↗