Effects of actin polymerization and Arp3 on nascent cap PM folds and tubules. (A) Coimaged PIP₂ probe and Jupiter-GFP after injection of Lat A or carrier control (DMSO) from late anaphase 11 (0 s) into telophase 11. Corner brackets show nascent cap PM fold redistributions over time. (B) Quantification of nascent cap PM fold areas relative to anaphase 11 (0 s) into telophase 11 for embryos injected with a carrier (blue) or LatA (red). Embryo values plotted. (C) Coimaged PIP₂ probe and Jupiter-GFP after injection of CK666 or control (CK689) from late anaphase 11 (0 s) into telophase 11. Corner brackets show nascent cap PM fold redistributions over time. (D) Quantification of nascent cap PM fold areas relative to anaphase 11 (0 s) into telophase 11 for embryos injected with CK689 control (blue) or CK666 (red). Embryo values plotted. (E) PIP₂ probe in control and Arp3 RNAi embryos at telophase 11. Corner brackets show PM folds (0 µm) and PM tubules (−1.5 µm). Pink bracket shows abnormal PIP₂ aggregation at pseudocleavage furrow in Arp3 RNAi. (F) Quantifications of nascent cap tubule numbers and depths in control and Arp3 RNAi embryos. Embryo values are plotted.