Scribble complex is a highly conserved polarity module that regulates apical-basal polarity in epithelial cells. The complex contains three proteins: Scribble (Scrib), Discs-Large (Dlg) and Lethal giant larvae (Lgl), which were originally identified in Drosophila as “neoplastic tumor suppressor genes” (nTSGs). Homozygous mutations in the nTSG genes lead to tumor formation in Drosophila imaginal discs and brain. Interestingly, if the nTSG gene mutant cells are induced as mosaic clones, the mutant clones are eliminated through a cell competition process. To identify genes regulating nTSG mutant cell growth outcome, we conducted a genome-wide genetic screening using chromosomal deficiency collections available in Drosophila.

Our screening results have shown that the growth outcome...[ Read more ]

Scribble complex is a highly conserved polarity module that regulates apical-basal polarity in epithelial cells. The complex contains three proteins: Scribble (Scrib), Discs-Large (Dlg) and Lethal giant larvae (Lgl), which were originally identified in Drosophila as “neoplastic tumor suppressor genes” (nTSGs). Homozygous mutations in the nTSG genes lead to tumor formation in Drosophila imaginal discs and brain. Interestingly, if the nTSG gene mutant cells are induced as mosaic clones, the mutant clones are eliminated through a cell competition process. To identify genes regulating nTSG mutant cell growth outcome, we conducted a genome-wide genetic screening using chromosomal deficiency collections available in Drosophila.

Our screening results have shown that the growth outcome of nTSG mutant cells is likely controlled by Drosophila innate immune system. Drosophila hemocytes are the innate immune surveillance cells. Here, we constructed a SpyTag/SpyCatcher system to capture transient interactions between hemocytes and the nTSG tumor cells. This system will lay the foundation for further investigation of innate immune response in Drosophila tumor models.