Annotation of microsporidian genomes usingtranscriptional signals

摘要

High-quality annotation of microsporidian genomes is essential for understanding thebiological processes that govern the development of these parasites. Here we presentan improved structural annotation method using transcriptional DnA signals. We applythis method to re-annotate four previously annotated genomes, which allow us to detectannotation errors and identify a significant number of unpredicted genes. We then annotatethe newly sequenced genome of Anncaliia algerae. A comparative genomic analysis ofA. algerae permits the identification of not only microsporidian core genes, but also potentiallyhighly expressed genes encoding membrane-associated proteins, which represent goodcandidates involved in the spore architecture, the invasion process and the microsporidian–host relationships. Furthermore, we find that the ten-fold variation in microsporidian genomesizes is not due to gene number, size or complexity, but instead stems from the presence oftransposable elements. such elements, along with kinase regulatory pathways and specifictransporters, appear to be key factors in microsporidian adaptive processes.