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Marti, M.

Publications and source records attributed to Marti, M..

3 recordsLinked to original sources

Validation of the protein kinase PfCLK3 as a multi-stage cross species malarial drug target

The requirement for next generation anti-malarials to be both curative and transmission blockers necessitate the identification of molecular pathways essential for viability of both asexual and sexual parasite life stages. Here we identify a selective inhibitor to the Plasmodium falciparum protein kinase PfCLK3 which we use in combination with chemogenetics, whole genome sequencing and transcriptomics to validate PfCLK3 as a druggable target acting at multiple parasite life stages. Consistent with the proposed role of PfCLK3 as a regulator of RNA splicing, inhibition results in the down-regulation of >400 genes essential for parasite survival. Through this mechanism, blocking PfCLK3 activity not only results in rapid killing of asexual blood stage parasites but is also effective on sporozoites and gametocytes as well as showing parasiticidal activity in all Plasmodium species tested. Hence, our data establishes PfCLK3 as a target with the potential to deliver both symptomatic treatment and transmission blocking in malaria.

microbiology

VarQ: a tool for the structural analysis of Human Protein Variants

Understanding the functional effect of Single Amino acid Substitutions (SAS), derived from the occurrence of single nucleotide variants (SNVs), and their relation to disease development is a major issue in clinical genomics. Even though there are several bioinformatic algorithms and servers that predict if a SAS can be pathogenic or not they give little or non-information on the actual effect on the protein function. Moreover, many of these algorithms are able to predict an effect that no necessarily translates directly into pathogenicity. VarQ Web Server is an online tool that given an UniProt id automatically analyzes known and user provided SAS for their effect on protein activity, folding, aggregation and protein interactions among others. VarQ assessment was performed over a set of previously manually curated variants, showing its ability to correctly predict the phenotypic outcome and its underlying cause. This resource is available online at http://varq.qb.fcen.uba.ar/.\n\nContact: lradusky@qb.fcen.uba.ar\n\nSupporting Information & Tutorials may be found in the webpage of the tool.

bioinformatics

Probabilistic data integration identifies reliable gametocyte-specific proteins and transcripts in malaria parasites

Plasmodium gametocytes are the sexual forms of the malaria parasite essential for transmission to mosquitoes. To better understand how gametocytes differ from asexual blood-stage parasites, we performed a systematic analysis of available omics data for P. falciparum and other Plasmodium species. 18 transcriptomic and proteomic data sets were evaluated for the presence of curated \"gold standards\" of 41 gametocyte-specific versus 46 non-gametocyte genes and integrated using Bayesian probabilities, resulting in gametocyte-specificity scores for all P. falciparum genes.\n\nTo illustrate the utility of the gametocyte score, we explored newly predicted gametocyte-specific genes as potential biomarkers of gametocyte carriage and exposure. We analyzed the humoral immune response in field samples against 30 novel gametocyte-specific antigens and found five antigens to be differentially recognized by gametocyte carriers as compared to malaria-infected individuals without detectable gametocytes. We also validated the gametocyte-specificity of 15 identified gametocyte transcripts on culture material and samples from naturally infected individuals, resulting in eight transcripts that were >1000-fold higher expressed in gametocytes compared to asexual parasites and whose transcript abundance allowed gametocyte detection in naturally infected individuals. Our integrated genome-wide gametocyte-specificity scores provide a comprehensive resource to identify targets and monitor P. falciparum gametocytemia.

microbiology