LvsA is a Dictyostelium protein that is essential for cytokinesis and that is related to the mammalian beige/LYST family of proteins. To better understand the function of this novel protein family we tagged LvsA with GFP using recombination techniques. GFP-LvsA is primarily associated with the membranes of the contractile vacuole system and it also has a punctate distribution in the cytoplasm. ...

During cell division, cytoplasmic organelles are not synthesized de novo, rather they are replicated and partitioned between daughter cells. Partitioning of the vacuole in the budding yeast Saccharomyces cerevisiae is coordinated with the cell cycle and involves a dramatic translocation of a portion of the parental organelle from the mother cell into the bud. While the molecular mechanisms that...

Abstract Plant cells contain two types of vacuoles, the lytic vacuole (LV) and protein storage (PSV). LVs are present in vegetative cells, whereas PSVs found seed cells. The physiological functions differ. Newly synthesized proteins must be transported to these vacuoles via trafficking through endomembrane system for them function. Recently, significant advances have been made elucidating molec...

Yeast vacuole protein targeting (vpt) mutants exhibit defects in the sorting and processing of multiple vacuolar hydrolases. To evaluate the impact these vpt mutations have on the biogenesis and functioning of the lysosome-like vacuole, we have used light and electron microscopic techniques to analyze the vacuolar morphology in the mutants. These observations have permitted us to assign the vpt...

Vac8p, an armadillo (ARM) repeat protein, is required for multiple vacuolar processes. It functions in vacuole inheritance, cytoplasm-to-vacuole protein targeting pathway, formation of the nucleus-vacuole junction and vacuole-vacuole fusion. These functions each utilize a distinct Vac8p-binding partner. Here, we report an additional Vac8p function: caffeine resistance. We show that Vac8p functi...

The plant vacuole is a central organelle that is involved in various biological processes throughout the plant life cycle. Elucidating the mechanism of vacuole biogenesis and maintenance is thus the basis for our understanding of these processes. Proper formation of the vacuole has been shown to depend on the intracellular membrane trafficking pathway. Although several mutants with altered vacu...

It has long been noted that larger animals have larger organs compared to smaller animals of the same species, a phenomenon termed scaling [1]. Julian Huxley proposed an appealingly simple model of "relative growth"-in which an organ and the whole body grow with their own intrinsic rates [2]-that was invoked to explain scaling in organs from fiddler crab claws to human brains. Because organ siz...

Previous studies have shown that L. pneumophila multiplies intracellularly in human monocytes and alveolar macrophages within a membrane-bound cytoplasmic vacuole studded with ribosomes. In this paper, the formation of this novel vacuole is examined. After entry into monocytes, L. pneumophila resides in a membrane-bound vacuole. During the first hour after entry, vacuoles containing L. pneumoph...