Movement of the multicellular slug stage of Dictyostelium discoideum; an analytical approach

Abstract
Time-lapse video recordings of migrating multicellular slugs of Dictyostelium discoideum were subjected to image analysis. A transient ‘collar-like’ structure was identified at the anterior end of the slug. This collar remains stationary in the wild-type strain WS380B; it is observed shortly after the advancing tip contacts the substratum. Stationary collars formed approximately every 12 min; they were matched with patterns revealed on the underside of slime trails with FITC-coupled monoclonal antibody MUD50. It is proposed that stationary collars are involved with the forward movement of the slug. The mutant strain HU2421 lacks the MUD50-epitope and forms collars which do not remain stationary but move backwards along the slug to collect at a ‘waist’ region. The slipping-collars observed in the mutant correlated with very slow migration rates. We propose thatHU2421 moves slowly because it lacks traction.