Required for the apical cell cortex localization, total cellular level and full activity of dachs. Interacts with dachs (via C-terminus); the interaction is direct. Interacts (via N-terminus including SH3 domain 1) with palmitoyltransferase app; this leads to palmitoylation of Dlish by app. Also interacts with dco, ft, ft-regulated E3 ubiquitin ligase Fbxl7, F-box protein slmb and SCF E3 ubiquitin-protein ligase complex component Cul1. Low levels are found diffusely in the cytoplasm with high levels concentrated at the subapical cell cortex. Palmitoylated by app. RNAi-mediated knockdown results in reduced spacing between the anterior and posterior crossveins of the wing, reduced levels of subapical cortical dachs, increased levels of dachs throughout the cytoplasm, increased total cellular levels of dachs and suppression of the overgrowth and dachs up-regulation seen in ft mutants.