Tethering factors are organelle-specific multisubunit protein complexes that identify, along with Rab guanosine triphosphatases, transport vesicles and trigger their SNARE-mediated fusion of specific transport vesicles with the target membranes. Little is known about how tethering factors discriminate between different trafficking pathways, which may converge at the same organelle. In this pape...

Vacuole biogenesis depends on specific targeting and retention of peripheral membrane proteins. At least three palmitoylated proteins are found exclusively on yeast vacuoles: the fusion factor Vac8, the kinase Yck3, and a novel adaptor protein implicated in microautophagy, Meh1. Here, we analyze the role that putative acyltransferases of the DHHC family play in their localization and function. ...

iV-methyl-AT-nitrosourea (MNU), methyl methane sulphonate (MMS), ethyl methane sulphonate (EMS) and cyclophosphamide (CP) are all cytotoxic to the transitional epithelium lining the urinary bladder, and also cause haemorrhage from the subepithelial blood capillaries. Erythrocytes enter the epithelium and are phagocytosed by the epithelial cells where they are subsequently digested. Two other co...

Toxoplasma gondii multiplies within parasitophorous vacuole that is not recognized by the primary no oxidative defense of host cells, mainly represented by the fusion with acidic organelles. Recent studies have already shown that hydroxyurea arrested the intracellular parasites leading to its destruction. In the present work we investigated the cellular mechanism involved in the destruction of ...

Previous studies of the yeast Saccharomyces cerevisiae indicated that the vacuole is a major site of zinc storage in the cell. However, these studies did not address the absolute level of zinc that was stored in the vacuole nor did they examine the abundances of stored zinc in other compartments of the cell. In this report, we describe an analysis of the cellular distribution of zinc by use of ...

Membrane fusion at the vacuole depends on a conserved machinery that includes SNAREs, the Rab7 homolog Ypt7 and its effector HOPS. Here, we demonstrate that Ypt7 has an unexpected additional function by controlling membrane homeostasis and nutrient-dependent signaling on the vacuole surface. We show that Ivy1, the yeast homolog of mammalian missing-in-metastasis (MIM), is a vacuolar effector of...

At low temperature, the short-chain fluorescent-labeled phospholipids, 1-myristoyl-2-[6-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) aminocaproyl]-phosphatidylcholine (M-C6-NBD-PC) and its phosphatidylethanolamine analog, M-C6-NBD-PE, are internalized by flip across the plasma membrane of S. cerevisiae and show similar enrichment in intracellular membranes including the mitochondria and nuclear envelope...

We have cloned the Schizosaccharomyces pombe homologue of the human Batten disease gene, CLN3. This gene, btn1, encodes a predicted transmembrane protein that is 30% identical and 48% similar to its human counterpart. Cells deleted for btn1 were viable but had enlarged and more alkaline vacuoles. Conversely overexpression of Btn1p reduced both vacuole diameter and pH. Thus Btn1p regulates vacuo...

Candida albicans forms unconstricted hyphae in serum-containing medium that are divided into discrete compartments. Time-lapse photomicroscopy, flow cytometry, and a novel three-dimensional imaging system were used to demonstrate that the kinetics and cell cycle events accompanying hyphal development were correlated with dynamic changes in vacuole morphology and the pattern of vacuole inheritan...

Toxoplasma gondii invades and proliferates in human umbilical vein endothelial cells where it resides in a parasitophorous vacuole. In order to analyze which components of the endothelial cell plasma membrane are internalized and become part of the parasitophorous vacuole membrane, the culture of endothelial cells was labeled with cationized ferritin or UEA I lectin or anti Class I human leukoc...