Fig. 4. Reduction of hipk results in loss of stabilized Arm protein. The expression of stabilized Arm was examined in wing discs bearing hipk⁴ mutant clones. (A) Wild-type third instar wing disc. A' is a magnification of A; A'' is a z-section through the disc. (B-D) hipk⁴ somatic clones were marked by the absence of GFP (green in C,D). Arm protein levels (red in B,D) were reduced in hipk somatic clones (arrowheads in B,D). B'-E' show higher magnification views of discs; B''-E'' show z-sections to reveal the subcellular localization of Arm. In hipk mutant cells, Arm levels were normal in the adherens junctions (arrowheads in B''). (E-E'') Expressing sd>hipk RNAi reduces overall Arm levels.