Developmental regulation of vesicle transport in Drosophila embryos: forces and kinetics. Author M Welte, S Gross, M Postner, S Block, E Wieschaus Publication Year 1998 Type Journal Article Abstract In Drosophila embryos, microtubules oriented along apical-basal directions support saltatory vesicle movement. Vesicle traffic includes lipid droplets whose distribution shifts twice during early embryogenesis. Using microscopy, optical tweezers, and a novel squashed-mount embryo preparation, we tracked single droplets and measured the forces these generated. Droplet stalling forces change developmentally, in a roughly quantized fashion, consistent with variation in the number of active motors. We characterized a mutation, klarsicht, that affects droplet transport. Klar+ facilitates changes in force, possibly by coordinating the activity of multiple motors. Alterations in transport affected motion in both apical and basal directions, indicating tight coupling between motors of opposite polarity. Mutations in klar also affect nuclear migration during eye development, suggesting multiple roles for klar-based transport. Keywords Animals, Drosophila, Larva, Microtubules, Cell Nucleus, Kinetics, Biological Transport, Insect Proteins, Mutagenesis, Kinesin, Eye, Lipid Metabolism, Intracellular Membranes Journal Cell Volume 92 Issue 4 Pages 547-57 Date Published 02/1998 Alternate Journal Cell Google ScholarBibTeXEndNote X3 XML