Interaction network of tobacco etch potyvirus NIa protein with the host proteome during infection.

BACKGROUND: The genomes of plant viruses have limited coding capacity, and to complete their infectious cycles, viral factors must target, direct or indirectly, many host elements. However, the interaction networks between viruses and host factors are poorly understood. The genus Potyvirus is the largest group of plus-strand RNA viruses infecting plants. Potyviral nuclear inclusion a (NIa) plays many roles during infection. NIa is a polyprotein consisting of two domains, viral protein genome-linked (VPg) and protease (NIaPro), separated by an inefficiently utilized self-proteolytic site. To gain insights about the interaction between potyviral NIa and the host cell during infection, we constructed Tobacco etch virus (TEV, genus Potyvirus) infectious clones in which the VPg or the NIaPro domains of NIa were tagged with the affinity polypeptide Twin-Strep-tag and identified the host proteins targeted by the viral proteins by affinity purification followed by mass spectrometry analysis (AP-MS). RESULTS: We identified 232 different Arabidopsis thaliana proteins forming part of complexes in which TEV NIa products were also involved. VPg and NIaPro specifically targeted 89 and 76 of these proteins, respectively, whereas 67 proteins were targeted by both domains and considered full-length NIa targets. Taking advantage of the currently known A. thaliana interactome, we constructed a protein interaction network between TEV NIa domains and 516 host proteins. The most connected elements specifically targeted by VPg were G-box regulating factor 6 and mitochondrial ATP synthase δ subunit; those specifically targeted by NIaPro were plasma membrane aquaporin PIP2;7 and actin 7, whereas those targeted by full-length NIa were heat shock protein 70-1 and photosystem protein LHCA3. Moreover, a contextualization in the global A. thaliana interactome showed that NIa targets are not more connected with other host proteins than expected by chance, but are in a position that allows them to connect with other host proteins in shorter paths. Further analysis of NIa-targeted host proteins revealed that they are mainly involved in response to stress, metabolism, photosynthesis, and localization. Many of these proteins are connected with the phytohormone ethylene. CONCLUSIONS: Potyviral NIa targets many host elements during infection, establishing a network in which information is efficiently transmitted.

Medication impact on oral health in schizophrenia / Impacto de los medicamentos en la salud bucal en la esquizofrenia

Background: Patients with schizophrenia constitute a particularly vulnerable group for oral diseases. Among thedifferent factors involved, we aimed to examine the evidence of how drugs could contribute to the poorer oralhealth of this population.Material and Methods: An overview of the potential impact of medication on dental/oral health among people withschizophrenia was proposed focusing on selected literature.Results: Studies show a higher dental caries and degree of periodontal diseases in this population and point todrug-induced xerostomia as an important risk factor for oral health deterioration. The risk of dry mouth dependson not only antipsychotics, but also drugs with anticholinergic activity. We hypothesize that antipsychotic inducedglycaemic alterations might contribute to reduced oral health, and that the antimicrobial activity of certain an-tipsychotics could have an impact on oral microbiota affecting oral condition. Pharmacovigilance data show thatinvoluntary movements are caused by typical and some atypical antipsychotics. Dry mouth is most frequentlyreported for quetiapine and olanzapine, while clozapine is more frequently associated with sialorrhea.Conclusions: Literature clearly shows higher caries and periodontal disease in schizophrenic patients. However,overall, there is scarce literature about the potential influence of drugs in these disorders. Health professionalsshould be aware of this issue in order to implement adequate preventive measures in this vulnerable population.(AU)