This paper provides a foundation for the polarity marking technique introduced by David Dowty [3] in connection with monotonicity reasoning in natural language and in linguistic analyses of negative polarity items based on categorial grammar. Dowty’s work is an alternative to the better-known algorithmic approach first proposed by Johan van Benthem [11], and elaborated by Vı́ctor Sánchez Valenci...

Rhizoctonia solani agglutinin, further referred to as RSA, is a lectin isolated from the plant pathogenic fungus Rhizoctonia solani. Previously, we reported a high entomotoxic activity of RSA towards the cotton leafworm Spodoptera littoralis. To better understand the mechanism of action of RSA, Drosophila melanogaster Schneider S2 cells were treated with different concentrations of the lectin a...

Recent studies have uncovered a key role of endocytosis during Notch signalling after the asymmetric division of the fly sensory organ precursor cells (SOP): directional signalling is mediated by differential endocytosis of the ligand Delta and the Notch effector Sanpodo in one of the SOP daughters, the pIIb. Here we show a novel mechanism of directional signalling based on the trafficking of D...

Previously we reported that internalized ligand-receptor complexes are transported within the alveolar macrophage at a rate that is independent of the ligand and/or receptor but is dependent on the endocytic apparatus (Ward, D. M., R. S. Ajioka, and J. Kaplan. 1989. J. Biol. Chem. 264:8164-8170). To probe the mechanism of intracellular vesicle transport, we examined the ability of vesicles inte...