ER localization relative to nascent cap PM folds and tubules, and to centrosomal MTs. (A) Single sections of co-expressed markers of PM (a PH-domain probe for PIP₃) and ER (KDEL-RFP) at telophase 11. PM folds of nascent cap (corner brackets) are mainly above ER. Arrows show PM tubules of nascent cap extending downward between ER regions. Seen in 5/5 embryos. (B) Single sections of co-expressed markers of MTs (Jupiter-GFP) and ER (KDEL-RFP) at telophase 11. Arrows show centrosomal astral MTs emanating upward through ER regions. Seen in 5/5 embryos.