CELL-PROLIFERATION PATTERNS IN THE WING IMAGINAL DISC OF DROSOPHILA

Morphogenetic processes, based on the temporal and spatial control of cell proliferation, are involved in determining the size and shape of an organism. We have used clonal analysis, employing X-ray-induced mit otic recombination, to study cell proliferation and differentiation pr ocesses in the developing wing imaginal disc of Drosophila. Our result s show a non-uniform distribution of mitotic activities during differe nt stages of wing development. This may reflect waves of cell prolifer ation which derive from distinct centers of cell proliferation within the growing wing imaginal disc. These proliferation centers are locate d within the major wing compartments (i.e. the anterior, posterior, do rsal and ventral compartments) and they are restricted to the areas wh ich give rise to the intervein regions of the adult wing. The mitotic recombination analysis, combined with the study of Minute and gynandro morph mosaics, show that the presumptive vein regions of the wing repr esent distinct boundaries which delimit the proliferation centers to t he intervein regions. We present a generative model of wing morphogene sis that is consistent with our results.