Here we show a requirement for the Cdc42 and Rac1 GTPases in endothelial cell (EC) morphogenesis in three-dimensional extracellular matrices. Cdc42 and Rac1 specifically regulate EC intracellular vacuole and lumen formation in both collagen and fibrin matrices. Clostridium difficile toxin B (which blocks all three Rho GTPases) completely inhibited the ability of ECs to form both vacuoles and lu...

As it grows within the human erythrocyte, the malaria parasite, Plasmodium falciparum, ingests the erythrocyte cytosol, depositing it via an endocytotic feeding mechanism in the "digestive vacuole," a specialized acidic organelle. The digestive vacuole is the site of hemoglobin degradation, the storage site for hemozoin (an inert biocrystal of toxic heme), the site of action of many antimalaria...

Nhx1p is a Na(+)(K(+))/H(+) antiporter localized at the vacuolar membrane of the yeast Saccharomyces cerevisiae. Nhx1p regulates the acidification of cytosol and vacuole lumen, and is involved in membrane traffic from late endosomes to the vacuole. Deletion of the gene leads to aberrant vacuolar morphology and defective vacuolar protein sorting. These phenotypes are hallmarks of malfunctioning ...

The ciliate Paramecium bursaria and the green alga Chlorella species can establish endosymbiosis by mixing them through the host digestive vacuoles. Pulse-labeling of alga-free Paramecium cells with isolated symbiotic algae for 1.5 min and chasing for various times showed presence of four cytological phenomena which are indispensable for the algal reinfection. (1) Some algae acquire temporal re...

Legionella pneumophila, the agent of Legionnaires' disease, is a facultative intracellular gram-negative bacterial pathogen (1) . The bacterium multiplies intracellularly in human blood monocytes (1) and human alveolar macrophages (2), and under tissue culture conditions, multiplication is exclusively intracellular . L. pneumophla enters monocytes by an unusual process-a monocyte pseudopod coil...

Invasive fungal infections are major threats for immunocompromised patients as well as for those undergoing cancer chemotherapy. Amphotericin B (AmB), a classical antifungal drug with a polyene macrolide structure, is widely used for the control of serious fungal infections. However, the clinical use of this antifungal drug is limited by its side effects and the emergence of drug-resistant stra...

Artemisinin is a powerful drug that has been combined with other antimalarial drugs to combat malaria and it crucial recent achievements in reducing cases. However, the emergence of Plasmodium falciparum resistance against artemisinin become serious problem treatment. Our previous studies reported alkalinised digestive vacuole P. similarly concanamycin A. Concanamycin A specific inhibitor V-typ...

The textbook image of the plant vacuole sitting passively in the centre of the cell is not always correct. We observed vacuole dynamics in the epidermal cells of red onion (Allium cepa) bulbs, using confocal microscopy to detect autofluorescence from the pigment anthocyanin. The central vacuole was penetrated by highly mobile transvacuolar strands of cytoplasm, which were also visible in concur...

A large number of trafficking steps occur between the last compartment of the Golgi apparatus (TGN) and the vacuole of the yeast Saccharomyces cerevisiae. To date, two intracellular routes from the TGN to the vacuole have been identified. Carboxypeptidase Y (CPY) travels through a prevacuolar/endosomal compartment (PVC), and subsequently on to the vacuole, while alkaline phosphatase (ALP) bypas...

The vacuole is the most prominent compartment in plant cells and is important for ion and protein storage. In our effort to search for key regulators in the plant vacuole sorting pathway, ribosomal large subunit 4 (rpl4d) was identified as a translational mutant defective in both vacuole trafficking and normal development. Polysome profiling of the rpl4d mutant showed reduction in polysome-boun...