Project description:The natural histories of various parasite-host interactions that involve adaptive manipulation of host behavior describe a time-of-day synchronization of certain events. One example is the manipulated biting behavior observed in Carpenter ants infected with Ophiocordyceps unilateralis sensu lato. Field observations in Thailand demonstrated that manipulated biting takes place around solar noon. Laboratory work with species from South Carolina, demonstrated a shift of this synchronized biting event to the early morning. We therefore hypothesize that biological clocks play an important role in these and other parasite-host interactions. To set the stage for our future research into this, we, here, aimed to explore if fungal species of the complex O. unilateralis s.l. have a functional molecular clock. We, therefore, performed RNA-Seq on time course samples of the recently sequenced species Ophiocordyceps kimflemingiae. Fungal blastospores grown in liquid media were harvested under cycling light-dark and continuous darkness conditions. Rhythmic mRNA levels were assessed with JTK_CYCLE. We found that O. kimflemingiae is not hugely rhythmic under our sampling conditions, but rhythmicity can be observed. Moreover, we identified functional homologs of known clock genes. In addition, our data indicated that regulation of transcription appears to take place during the light phase (day time). In contrast, the expression levels of a significant number of secreted enzymes, proteases, toxins and small bioactive compounds peaked during the dark phase (night time). This suggests that this fungal parasite might indeed rely on biological clocks for the precise daily timing of certain events and additionally validates further research into this.
Project description:Transcriptional profiling of NHDF Cells comparing control untreated fibroblasts with fibroblasts coincubated with three different species of the Borrelia burgdorferi sensu lato group.
Project description:The parasite species complex Anisakis simplex sensu lato (Anisakis simplex sensu stricto; (A. simplex s.s.), A. pegreffii, A. simplex C) is the main cause of severe anisakiasis (allergy) worldwide and is now an important health matter. In this study, the relationship of this Anisakis species complex and their allergenic capacities is assessed by studying the differences between the two most frequent species (A. simplex s.s., A. pegreffii) and their hybrid haplotype by studying active L3 larvae parasiting Merluccius merluccius.
Project description:Transcriptional control of gene expression is a result of complex interactions between the cis-regulatory elements (CRE) at gene promoters. To understand the regulatory logic of a cell, we need to identify the CRE combinations that regulate gene expression. We developed a sensitive computational method to identify phylogenetically conserved CRE combinations for any species of interest. In contrast to previous methods, we do not need to align genomes to identify these combinations. We applied the method in 7 sensu stricto and sensu lato Saccharomyces species. 80% of the predictions displayed some evidence of combinatorial transcriptional behavior in several existing datasets including 1) ChIP-chip data for co-localization of transcription factors, 2) gene expression data for co-expression of predicted regulatory targets, and 3) gene ontology databases for common pathway membership of predicted regulatory targets. To establish definitive evidence that these CRE interactions influence TF occupancy, we performed ChIPseq experiments on transcription factors in a wild-type strain and strains in which a predicted cofactor was deleted. Our experiments showed that TF occupancy at the promoters of the CRE combination target genes depends on the predicted cofactor while occupancy of other promoters is independent of the predicted cofactor. ChIP-seq of 6 myc-tagged Transcription factors in wild-type and predicted co-factor knockout yeast strains in triplicate
