Refractile bodies of are proteinaceous membrane-less organelles that undergo dynamic changes during infection.

Introduction: Refractile bodies (RB) are large membrane-less organelles (MLO) of unknown function found as a prominent mismatched pair within the sporozoite stages of all species of , parasitic coccidian protozoa.

Methods: High resolution imaging methods including time-lapse live confocal microscopy and serial block face-scanning electron microscopy (SBF-SEM) were used to investigate the morphology of RB and other intracellular organelles before and after sporozoite invasion of host cells.

Results: Live cell imaging of MDBK cells infected with sporozoites confirmed previous reports that RB reduce from two to one post-infection and showed that reduction in RB number occurs merger of the anterior RB with the posterior RB, a process that lasts 20-40 seconds and takes place between 2- and 5-hours post-infection.

Cellular electron tomography of the apical complex in the apicomplexan parasite Eimeria tenella shows a highly organised gateway for regulated secretion.

The apical complex of apicomplexan parasites is essential for host cell invasion and intracellular survival and as the site of regulated exocytosis from specialised secretory organelles called rhoptries and micronemes. Despite its importance, there are few data on the three-dimensional organisation and quantification of these organelles within the apical complex or how they are trafficked to this specialised region of plasma membrane for exocytosis. In coccidian apicomplexans there is an additional tubulin-containing hollow barrel structure, the conoid, which provides a structural gateway for this specialised apical secretion.

Do All Coccidia Follow the Same Trafficking Rules?

The Coccidia are a subclass of the Apicomplexa and include several genera of protozoan parasites that cause important diseases in humans and animals, with becoming the 'model organism' for research into the coccidian molecular and cellular processes. The amenability to the cultivation of tachyzoites and the wide availability of molecular tools for this parasite have revealed many mechanisms related to their cellular trafficking and roles of parasite secretory organelles, which are critical in parasite-host interaction. Nevertheless, the extrapolation of the mechanisms described in tachyzoites to other coccidian parasites should be done carefully.

Adipose triglyceride lipase protects renal cell endocytosis in a Drosophila dietary model of chronic kidney disease.

Obesity-related renal lipotoxicity and chronic kidney disease (CKD) are prevalent pathologies with complex aetiologies. One hallmark of renal lipotoxicity is the ectopic accumulation of lipid droplets in kidney podocytes and in proximal tubule cells. Renal lipid droplets are observed in human CKD patients and in high-fat diet (HFD) rodent models, but their precise role remains unclear.

The Growth of : Characterization and Application of Quantitative Methods to Assess Sporozoite Invasion and Endogenous Development in Cell Culture.

development of the complete life cycle of species has been achieved in primary cultures of avian epithelial cells with low efficiency. The use of immortalized cell lines simplifies procedures but only allows partial development through one round of parasite invasion and intracellular replication. We have assessed the suitability of Madin-Darby Bovine Kidney (MDBK) cells to support qualitative and quantitative studies on sporozoite invasion and intracellular development of .

A lipocalin mediates unidirectional heme biomineralization in malaria parasites.

During blood-stage development, malaria parasites are challenged with the detoxification of enormous amounts of heme released during the proteolytic catabolism of erythrocytic hemoglobin. They tackle this problem by sequestering heme into bioinert crystals known as hemozoin. The mechanisms underlying this biomineralization process remain enigmatic.

Suramin exposure alters cellular metabolism and mitochondrial energy production in African trypanosomes.

Introduced about a century ago, suramin remains a frontline drug for the management of early-stage East African trypanosomiasis (sleeping sickness). Cellular entry into the causative agent, the protozoan parasite , occurs through receptor-mediated endocytosis involving the parasite's invariant surface glycoprotein 75 (ISG75), followed by transport into the cytosol via a lysosomal transporter. The molecular basis of the trypanocidal activity of suramin remains unclear, but some evidence suggests broad, but specific, impacts on trypanosome metabolism ( polypharmacology).

Marked and rapid effects of pharmacological HIF-2α antagonism on hypoxic ventilatory control.

Hypoxia-inducible factor (HIF) is strikingly upregulated in many types of cancer, and there is great interest in applying inhibitors of HIF as anticancer therapeutics. The most advanced of these are small molecules that target the HIF-2 isoform through binding the PAS-B domain of HIF-2α. These molecules are undergoing clinical trials with promising results in renal and other cancers where HIF-2 is considered to be driving growth.

Life cycle stages, specific organelles and invasion mechanisms of species.

Apicomplexans, including species of Eimeria, pose a real threat to the health and wellbeing of animals and humans. Eimeria parasites do not infect humans but cause an important economic impact on livestock, in particular on the poultry industry. Despite its high prevalence and financial costs, little is known about the cell biology of these 'cosmopolitan' parasites found all over the world.

Nuclear membrane protein Lem2 regulates nuclear size through membrane flow.

The size of the membrane-bound nucleus scales with cell size in a wide range of cell types but the mechanisms determining overall nuclear size remain largely unknown. Here we investigate the role of fission yeast inner nuclear membrane proteins in determining nuclear size, and propose that the Lap2-Emerin-Man1 domain protein Lem2 acts as a barrier to membrane flow between the nucleus and other parts of the cellular membrane system. Lem2 deletion increases membrane flow into and out of the nuclear envelope in response to changes in membrane synthesis and nucleocytoplasmic transport, altering nuclear size.

Transcriptome, proteome and draft genome of Euglena gracilis.

Background: Photosynthetic euglenids are major contributors to fresh water ecosystems. Euglena gracilis in particular has noted metabolic flexibility, reflected by an ability to thrive in a range of harsh environments. E.