This observation places Warts in the forefront of current interest in the genes that act as central regulators of the cell cycle. Other genes related to warts , namely those more closely related to the mammalian myotonic dystrophy kinase, interact physically with the cytoskeleton regulator Rho, and it is still not clear whether the warts branch of the family functions exclusively as a cell cycle regulator or whether Warts itself also functions in regulating the cytoskeleton. This question will be dealt with more extensively below. The loss of wts gene function leads to the cell-autonomous formation of epithelial tumors in the adult integumentary structures derived from imaginal discs.
Clones have smooth edges and are round or elliptical in shape on legs and especially wings .
The rounded shape of wts clones suggests that the divisions of cells lacking wts gene function are not oriented preferentially, as the clones appear to be in wild-type imaginal discs, or that there is a defect in cell adhesion that leads to abnormal cell arrangements. Although mutations at wts cause many defects, an effect on cell proliferation could cause most of the phenotypes including overproliferation in mutant clones, lethality at the various stages, tissue overproliferation on the head, broadened wing blade and sterility in homozygous mutants. The different behavior of the wts mutant clones and clones mutant for other previously identified Drosophila tumor suppressors points to multiple functions carried out by the different tumor suppressors. In contrast, the warts mutant clones induced during the larval stages are overproliferated and, later, the mutant cells on the body are differentiated to form adult cuticular structures. Clues as to the function of warts comes from the cloning of the human and mouse warts homologs.