A MINUTE ENCODING A RIBOSOMAL-PROTEIN ENHANCES WING MORPHOGENESIS MUTANTS

E(Dl)KP135 has been isolated previously as a recessive lethal Drosophi la P element insertion line with a dominant enhancing effect on the ph enotype of Delta, a gene encoding a surface membrane protein. We show here that this P insertion also enhances the wing phenotype of nd1, an allele of Notch encoding another transmembrane protein, the putative receptor of Delta, as well as that of if3, an allele of the integrin g ene PS2alpha. Moreover, we noticed that this P insertion causes a seve re Minute phenotype. Molecular characterisation revealed that the P el ement disrupts the putative mRNA leader sequence of the ribosomal prot ein L19 gene. We tested further Minute genes and found that two of the m, similarly to E(Dl)KP135, strongly enhance the nd1 wing phenotype. O ur results suggest that the pleiotropic Minute syndrome can affect, pr obably indirectly, one or more steps of wing morphogenesis that involv e surface adhesion of epithelial cells.