Tyrosine phosphorylation of Abi inhibits its functions in CME and crystal cell development. (A) Confocal images of primary hemocytes from WT, abi⁵/Df, HmlΔ-GAL4,abi⁵/UAS-HA-abi^4YF,Df (abi⁵/Df, HmlΔ > abi^4YF), and HmlΔ-GAL4,abi⁵/UAS-HA-abi^4YE,Df (abi⁵/Df, HmlΔ > abi^4YE) late-third instar larvae. Hemocytes were pulsed with Alexa Fluor 555-mBSA for 5 min, chased for 5 min, and stained with DAPI. (B) Quantification of the ratio of mean Alexa Fluor 555-mBSA to DAPI fluorescence intensities. Values are presented as percentages of HmlΔ-GAL4/+. n = 30 hemocytes. (C) Single confocal slices of primary hemocytes from abi⁵/Df larvae carrying HmlΔ-GAL4 and UAS-HA-Abi-4YF or UAS-HA-Abi-4YE, pretreated with 100 μM dynasore for 30 min prior to immunofluorescence analysis using anti-HA (green), anti-WASp (pseudocolored magenta), and anti-Chc (blue) antibodies. (D) Quantification of HA-Abi-Chc colocalization. (E) Quantification of WASp-Chc colocalization. (F) Quantification of HA-Abi-WASp colocalization. (G) Bright-field images of heated (70°C, 10 min) late-third instar larvae of the indicated genotypes. (H) Number of heat-blackened crystal cells in the A7 and A8 segments. n = 12 larvae. (I) Confocal images of peripheral hemocytes from late-third instar larvae of indicated genotypes, stained with an anti-L1 antibody (green) and DAPI (blue). Arrowheads indicate L1⁺ lamellocytes. (J) Percentage of L1⁺ lamellocytes among all peripheral hemocytes (total DAPI count). Data represent the mean ± SEM. Statistical analyses are performed using a one-way ANOVA with the Tukey–Kramer post hoc test (**P < 0.01; ***P < 0.001). Scale bars: 5 μm (A); 10 μm (C); 20 μm (I); 200 μm (G).