(A) IF images of early prophase nuclei stained for PLK-2 and SUN-1 phosphorylated on Ser12 (SUN-1 S12-Pi) in wild-type and hal-2 animals. In the wild-type nuclei, SUN-1 S12-Pi and PLK-2 are concentrated together in bright patches at the nuclear envelope (NE). In the hal-2 nuclei, PLK-2 and SUN-1 S12-Pi are not detected. Bar, 2 µm. (B) IF images of early prophase nuclei stained for ZYG-12::GFP and SUN-1 phosphorylated on Ser8 (SUN-1 S8-Pi) in wild-type and hal-2 animals carrying the zyg-12::gfp transgene. In the wild-type nuclei, SUN-1 S8-Pi and ZYG-12::GFP are concentrated together in bright patches at the NE and are also detected at lower levels throughout the entire NE. In the hal-2 nuclei shown, SUN-1 S8-Pi is not detected and ZYG-12::GFP is dispersed throughout the NE. Bar, 2 µm. (C) IF images of ZIM-2 (chromosome V PC-binding protein) in early prophase nuclei. A single bright focus near the NE is observed in the wild-type nuclei, whereas none is detected in the hal-2 mutant nuclei. Bar, 2 µm.