Increase in ECHOvirus 6 infections associated with neurological symptoms in the Netherlands, June to August 2016

The Dutch virus-typing network VIRO-TypeNed reported an increase in ECHOvirus 6 (E-6) infections with neurological symptoms in the Netherlands between June and August 2016. Of the 31 cases detected from January through August 2016, 15 presented with neurological symptoms. Ten of 15 neurological cases were detected in the same province and the identified viruses were genetically related. This report is to alert medical and public health professionals of the circulation of E-6 associated with neurological symptoms

Re-emergence of enterovirus D68 in Europe after easing the COVID-19 lockdown, September 2021

We report a rapid increase in enterovirus D68 (EV-D68) infections, with 139 cases reported from eight European countries between 31 July and 14 October 2021. This upsurge is in line with the seasonality of EV-D68 and was presumably stimulated by the widespread reopening after COVID-19 lockdown. Most cases were identified in September, but more are to be expected in the coming months. Reinforcement of clinical awareness, diagnostic capacities and surveillance of EV-D68 is urgently needed in Europe.Peer Reviewe

Molecular epidemiology and evolutionary trajectory of emerging echovirus 30, Europe

In 2018, an upsurge in echovirus 30 (E30) infections was reported in Europe. We conducted a large-scale epidemiologic and evolutionary study of 1,329 E30 strains collected in 22 countries in Europe during 2016-2018. Most E30 cases affected persons 0-4 years of age (29%) and 25-34 years of age (27%). Sequences were divided into 6 genetic clades (G1-G6). Most (53%) sequences belonged to G1, followed by G6 (23%), G2 (17%), G4 (4%), G3 (0.3%), and G5 (0.2%). Each clade encompassed unique individual recombinant forms; G1 and G4 displayed >= 2 unique recombinant forms. Rapid turnover of new clades and recombinant forms occurred over time. Clades G1 and G6 dominated in 2018, suggesting the E30 upsurge was caused by emergence of 2 distinct clades circulating in Europe. Investigation into the mechanisms behind the rapid turnover of E30 is crucial for clarifying the epidemiology and evolution of these enterovirus infections.Molecular basis of virus replication, viral pathogenesis and antiviral strategie

The role of abscisic acid in ethylene-induced elongation

Rumex palustris responds to submergence with an upward bending of the petioles (hyponastic growth) followed by a strong enhancement of elongation of the entire petiole. These two growth responses together help the plant to regain contact with the water surface, so that gas exchange to the submerged tissue can be restored. The underwater escape response is initiated by ethylene, which accumulates inside the submerged tissue (Voesenek et al., 1993). Almost immediately after submergence, ethylene induces a reduction in the concentration of abscisic acid (ABA, Chapter 2), via an increase in ABA catabolism and a depression of ABA biosynthesis. Externally applied ABA can almost fully inhibit underwater growth, while an artificial reduction in ABA enhances the elongation response by shortening the distinct lag phase between the start of submergence and the start of faster elongation growth. Submergence of the submergence-intolerant R. acetosa, a species related to R. palustris but incapable of enhanced submergence-induced elongation, does not lead to a decrease in ABA (Chapter 2). ABA is still a negative regulator of enhanced growth even in R. acetosa, as fluridone treatment permits enhanced underwater extension growth in submerged R. acetosa. Air-grown R. acetosa does not show enhanced elongation upon fluridone treatment. Since pre-treatment with the ethylene action inhibitor 1-MCP does not prevent underwater elongation in fluridone-treated R. acetosa, there must be a submergence signal other than ethylene that stimulates the petioles of R. acetosa to extend rapidly. Whatever the signal eventually proves to be, it is seemingly inactive in R. palustris, where submergence-induced elongation can be inhibited fully by 1-MCP. In R. palustris, submergence induces an up-regulation of the concentration of GA1. This up-regulation results predominantly from increased transcription of RpGA3ox1, a gibberellin biosynthesis gene the product of which catalyses the final enzymatic step to form GA1 (Chapter 4). Submergence induces an acidification of the apoplast of petiole cells, mediated by an increase in H+ efflux activity (Chapter 5). This acidification process facilitates the action of cell wall-loosening proteins, such as the expansin RpExp1. The submergence-induced apoplastic acidification is found to be independent of ABA as it takes place prior to a decrease in ABA concentration, and externally applied ABA fails to inhibit the acidification (Chapter 2 and 5). Thus, in the signal transduction pathway of submergence-induced elongation, apoplastic acidification and RpEXP1 expression are placed downstream of ethylene, but parallel to ABA (Fig. 1). Hyponastic growth Hyponastic growth is an important component of the underwater escape mechanism in R. palustris. The response is regulated by ABA. Application of this hormone to submerged plants inhibits hyponastic growth, while pre-treatment with fluridone induces an enhanced hyponastic response in submerged or ethylene-treated plants (Chapter 3). Arabidopsis thaliana responds to ethylene (5 µL L-1) with a hyponastic growth response (Millenaar et al., unpublished). This process is thought to consist of enhanced cell extension on the abaxial side of the petiole. The magnitude of this response varies strongly Columbia-0 (Col), showing strong hyponastic growth, and Landsberg erecta (Ler) showing little hyponasty. Aba negatively influence petiole angles. ABA and fluridone were less effective in altering hyponasty in Ler than in Col. Ethylene did not decrease ABA in petioles of ethylene-treated Arabidopsis. However, ethylene did increase the transcript abundance of ABI1, a negative regulator of ABA signal transduction

Quantitative phospho-proteomics of early elicitor signalling in Arabidopsis

Perception of general elicitors by plant cells initiates signal transduction cascades that are regulated by protein phosphorylation. The earliest signaling events occur within minutes and include ion fluxes across the plasma membrane, activation of MAPKs, and the formation of reactive oxygen species. The phosphorylation events that regulate these signaling cascades are largely unknown. Here we present a mass spectrometry-based quantitative phosphoproteomics approach that identified differentially phosphorylated sites in signaling and response proteins from Arabidopsis cells treated with either flg22 or xylanase. Our approach was sensitive enough to quantitate phosphorylation on low abundance signaling proteins such as calcium-dependent protein kinases and receptor-like kinase family members. With this approach we identified one or more differentially phosphorylated sites in 76 membrane-associated proteins including a number of defense-related proteins. Our data on phosphorylation indicate a high degree of complexity at the level of post-translational modification as exemplified by the complex modification patterns of respiratory burst oxidase protein D. Furthermore the data also suggest that protein translocation and vesicle traffic are important aspects of early signaling and defense in response to general elicitors. Our study presents the largest quantitative Arabidopsis phosphoproteomics data set to date and provides a new resource that can be used to gain novel insight into plant defense signal transduction and early defense response

VIRO-TypeNed, systematic molecular surveillance of enteroviruses in the Netherlands between 2010 and 2014.

Contains fulltext : 165835.pdf (publisher's version ) (Open Access