The nuclear envelope (NE) separates translation and transcription and is the location of multiple functions, including chromatin organization and nucleocytoplasmic transport. The molecular basis for many of these functions have diverged between eukaryotic lineages. , a member of the early branching eukaryotic lineage Discoba, highlights many of these, including a distinct lamina and kinetochore composition.
View Article and Find Full Text PDFIn trypanosomatids, transcription is polycistronic and all mRNAs are processed by trans-splicing, with export mediated by noncanonical mechanisms. Although mRNA export is central to gene regulation and expression, few orthologs of proteins involved in mRNA export in higher eukaryotes are detectable in trypanosome genomes, necessitating direct identification of protein components. We previously described conserved mRNA export pathway components in Trypanosoma cruzi, including orthologs of Sub2, a component of the TREX complex, and eIF4AIII (previously Hel45), a core component of the exon junction complex (EJC).
View Article and Find Full Text PDFReconstruction of the evolutionary history of specific protein-coding genes is an essential component of the biological sciences toolkit and relies on identification of orthologs (a gene in different organisms related by vertical descent from a common ancestor and usually presumed to have the same or similar function) and paralogs (a gene related to another in the same organism by descent from a single ancestral gene which may, or may not, retain the same/similar function) across a range of taxa. While obviously essential for the reconstruction of evolutionary histories, ortholog identification is of importance for protein expression, modeling for drug discovery programs, identification of critical residues and other studies. Here we describe an automated system for searching for orthologs and paralogs in eukaryotic organisms.
View Article and Find Full Text PDFEukaryotic cells arose ~1.5 billion years ago, with the endomembrane system a central feature, facilitating evolution of intracellular compartments. Endomembranes include the nuclear envelope (NE) dividing the cytoplasm and nucleoplasm.
View Article and Find Full Text PDFDinoflagellates are algae of tremendous importance to ecosystems and to public health. The cell biology and genome organization of dinoflagellate species is highly unusual. For example, the plastid genomes of peridinin-containing dinoflagellates encode only a minimal number of genes arranged on small elements termed "minicircles".
View Article and Find Full Text PDFThe dinoflagellates are an extremely diverse group of algae closely related to the Apicomplexa and the ciliates. Much work has previously been undertaken to determine the presence of various biochemical pathways within dinoflagellate mitochondria. However, these studies were unable to identify several key transcripts including those encoding proteins involved in the pyruvate dehydrogenase complex, iron-sulfur cluster biosynthesis, and protein import.
View Article and Find Full Text PDFThe isolation and characterisation of a novel protist lineage enables the reconstruction of early evolutionary events that gave rise to ciliates, malaria parasites, and coral symbionts. These events include dramatic changes in mitochondrial genome content and organisation.
View Article and Find Full Text PDFThe dinoflagellates are an important group of eukaryotic, single celled algae. They are the sister group of the Apicomplexa, a group of intracellular parasites and photosynthetic algae including the malaria parasite Plasmodium. Many apicomplexan mitochondria have a number of unusual features, including the lack of a pyruvate dehydrogenase and the existence of a branched TCA cycle.
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