Dissociation and sorting out of Drosophila imaginal disc cells.

Previous attempts to study sorting out of Drosophila imaginal disc cells have been hampered by an inability to thoroughly dissociate these cells and the need to use cuticular markers which require several days of in vivo culture. This study overcomes these limitations by using a new dissociation procedure and a genetic marker for undifferentiated cells, the succinate dehydrogenase8 (sdh8) mutation. Dissociated and reaggregated cells from wing and leg imaginal discs segregated or "sorted out" from one another after only 24 hr of in vivo culture. It was also found that leg cells from different body segments may sort out, but to a lesser degree than wing and leg cells. Mixtures of wing and haltere cells did not sort out, in contrast to previous reports. These results constitute the first unambiguous study of sorting out with Drosophila imaginal disc cells and indicate that dorsally situated imaginal cells share a recognition specificity which is different from that of ventral imaginal cells.